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To help health economic modelers respond to demands for greater use of complex systems models in public health. To propose identifiable features of such models and support researchers to plan public health modeling projects using these models. A working group of experts in complex systems modeling and economic evaluation was brought together to develop and jointly write guidance for the use of complex systems models for health economic analysis. The content of workshops was informed by a scoping review. A public health complex systems model for economic evaluation is defined as a quantitative, dynamic, non-linear model that incorporates feedback and interactions among model elements, in order to capture emergent outcomes and estimate health, economic and potentially other consequences to inform public policies. The guidance covers: when complex systems modeling is needed; principles for designing a complex systems model; and how to choose an appropriate modeling technique. This paper provides a definition to identify and characterize complex systems models for economic evaluations and proposes guidance on key aspects of the process for health economics analysis. This document will support the development of complex systems models, with impact on public health systems policy and decision making.

Broadband Internet provision is an increasing demand in many rural areas and wireless internet service providers have emerged as an opportunity to fill this need. However, this type of operator typically consists of a small business with little resources, and difficulty to plan and assess a reliable and economically sustainable infrastructure. In this paper, we try to bring some aid to this challenging problem by describing a reliable mesh-based backhaul design, together with a detailed CapEx/OpEx economic assessment. We apply our model using real data from ten Italian rural municipalities. Our numerical results show that having clusters of 200 subscribers, a reliable backhaul could be deployed with a monthly subscription and price per Mb/s extremely competitive compared to existing market offers. This work has received funding through the Spanish grant PID2019-106774RB-C21 and Generalitat de Catalunya through 2017-SGR-990.

In order to arrive in an econometric model for the analysis of the budget of the communities, the research of the explanatory or theoretical models proposes an analysis of the elements influencing the behavior of the budget of the Municipalities based on the assumption of a trade-off between considerations of autonomous factors of the local sector growth (electoral cycle, behavior of elected officials, inflation…) and short-term considerations of political constraints. The breakdown of these explanatory factors leads us to a global entry, where the explanatory variables of three types: - a macroeconomic variable representative of the economic situation: the rate of inflation, economic growth and rate of fiscal pressure; - budgetary variables representing the financial situation of Local Authorities: total expenditure, total revenue, subsidies and endowments, and time of treasury depletion (where the time between the waiting time for the free funds existing at the General Treasury, for providing an instance for the payment of expenses); - a variable representing the effectiveness of the treasury forecasts and the management of the Local Authority: cash desired in order to standardize the assessment procedures of several Municipalities. In future research, these theoretical or explanatory models will make it possible to prepare an econometric analysis study for a better prediction and budget simulation.

This paper aims to display benefits of applying economic modeling to predict the most economic treatment among three wastewater treatment plants containing conventional activated sludge without denitrification (CAS), conventional activated sludge with pre-denitrification (CAS-N), and membrane bioreactor (MBR) using CapdetWorks (v.3) simulation software. The software was run for each alternative with an average flow of 30,000 m3/d to calculate and evaluate the current worth costs of these WWTPs. Besides, the price per cubic meter of influent flow of the WWTPs has been evaluated. Tikrit WWTP was selected as a case study. Results demonstrated that the current worth cost of the MBR plant is higher than that for the CAS and CAS-N by about 57%, 42% respectively. Furthermore, the price per cubic meter of influent flow of the CAS plant is 0.2 $/m3. Dissimilarity, costs of the CAS-N and MBR plants are 0.27 $/m3 and 0.43 $/m3 respectively. The low cost of the CAS comes with lower removal efficiencies in comparison to the CAS-N and MBR. Accordingly, the economic modeling is helpful to build and compare relative costs for treatment alternatives which lead to better engineering decisions and suitable selection of the appropriate treatment based on either cost or effluent quality.

Respiratory syncytial virus (RSV) is the most common cause of pediatric acute lower respiratory tract infection worldwide. Detailed data on the health and economic burden of RSV disease are lacking from tropical settings with year-round RSV transmission. We developed a statistical and economic model to estimate the annual incidence and healthcare cost of medically attended RSV disease among young children in Singapore, using Monte Carlo simulation to account for uncertainty in model parameters. RSV accounted for 708 hospitalizations in children

**Background:** In order to facilitate sound economic evaluations of novel treatments, health-economic models of polycythemia vera (PV) must combine effects on surrogate endpoints in trials with disease progression (DP) and mortality in long-term cohort data. **Objective:** We validate an economic model for PV that uses Janus Kinase 2 (JAK2) burden as a surrogate endpoint to predict DP (thrombosis, myelofibrosis, and acute leukemia) and overall survival (OS) based on progression-specific mortality. **Methods:** Long-term observational studies that include information about baseline JAK2 burden were identified via PubMed searches and used to validate the model. Kaplan-Meier (KM) OS curves were extracted using a digitizing software. External validity of the model was analyzed by visually comparing OS curves of the model with the KM curves of the included studies, as well as calculating differences in mean OS estimated as area under the curve (AUC). **Results:** The model’s predictions of cumulative DP were somewhat lower than the published studies. Over 20 years’ time, our base case model predicted a mean OS for a PV patient (15.0–16.5 years), which was in line with the published studies (15.8–17.5 years). Modeled mean OS was almost two years longer (1.6–1.9 years) for patients with JAK2

Purpose . Assessment of the socio-economic burden of COVID-19 in the Russian Federation (RF). Materials and methods . Identification and assessment of direct medical, direct non-medical costs, as well as indirect costs associated with the development of the coronavirus infection epidemic. When calculating the socio-economic burden, the prevalence-based calculation approach was chosen. The sources of data on the epidemiology of the disease were data from the Ministry of Health and data from the Government of the Russian Federation. Results . The socio-economic burden of COVID-19 in the Russian Federation will amount to 4.6 trillion rubles ($71.1 billion) or 4 % from GDP. In the cost structure, more than half of the costs are direct non-medical expenses (58.62 %), indirect expenses due to GDP losses are 40.65 %, direct medical expenses are only less than 1 % (0.74 %). The results of the sensitivity analysis showed that the extension of the self-isolation period from 1 month to 1.5 and 2 months will lead to an increase in the share of indirect expenses from 40.65 % (1 month) to 56.08 (1.5 months) and 67.76 % (2 months) for all expenses in connection with the COVID-19 epidemic. At the same time, the socio-economic burden of COVID-19 will amount to 6.2 and 8.5 trillion rubles, respectively. Conclusions . The epidemic of a novel coronavirus infection will lead to great economic losses in the Russian society.

This paper seeks to convince historians that investigating how tractability has shaped individual and collective modeling choices in economics is a valuable endeavor. To do so, I first survey the economic methodology literature on tractability, one that grew out of methodologists’ attempts to explain why their authors make unrealistic assumptions. I then compare these accounts with the few instances where 20th century economists discussed tractability explicitly. This short survey suggests that there is a need for historians to document the collective dynamics at work when tractability motives are invoked. I suggest that disentangling theoretical, empirical and computational tractability might be fruitful, but also difficult. I ask how and why choices made for tractability purposes meant to be idiosyncratic and temporary often become collectively entrenched, sometimes creating “tractability traps.” Finally, I consider the existence of “tractability standards” that differ across time and fields. Cet article cherche à convaincre les historiens de se pencher sur la manière dont la « tractabilité », traduction directe de l’anglais tractability, a influencé les choix de modélisation individuels et collectifs en économie. Pour ce faire, je passe en revue la littérature en épistémologie économique sur le sujet. Celle-ci dérive des travaux visant à comprendre pourquoi les économistes font des hypothèses irréalistes. J’analyse ensuite les rares exemples où les économistes du 20ème siècle ont explicitement discuté du problème de la tractabilité. J’en conclue que la dimension collective des dynamiques par lesquelles les économistes rendent leurs modèles manipulables et solvables est un élément important et sous-étudié de l’analyse économique. Les choix de modélisation qui répondent à des impératifs de tractabilité sont souvent censés être temporaires et ad hoc, mais n’en deviennent pas moins des conventions collectives, créant des « trappes à tractabilité ». Je considère aussi l’existence de « standards de tractabilité » qui diffèrent selon les époques et les spécialités. Je suggère enfin de distinguer trois types de tractabilité : théorique, empirique et computationnelle.

Background: Hepatitis C virus (HCV) genotype 1 is the most prevalent HCV infection in China. Sofosbuvir-based direct antiviral agent (DAA) regimens are the current mainstays of treatment. Sofosbuvir/velpatasvir (SOF/VEL) and sofosbuvir/ledipasvir (SOF/LDV) regimens became reimbursable in China in 2020. Thus, this study aimed to identify the optimal SOF-based regimen and to inform efficient use of healthcare resources by optimizing DAA use in treating HCV genotype 1.Methods and Models: A modeling-based cost-utility analysis was conducted from the payer's perspective targeting adult Chinese patients with chronic HCV genotype 1 infection. Direct medical costs and health utilities were inputted into a Markov model to simulate lifetime experiences of chronically infected HCV patients after receiving SOF/LDV, SOF/VEL or the traditional strategy of pegylated interferon (pegIFN) + ribavirin (RBV). Discounted lifetime cost and quality adjusted life years (QALYs) were computed and compared to generate the incremental cost utility ratio (ICUR). An ICUR below the threshold of 31,500 $/QALY suggests cost-effectiveness. Deterministic and probabilistic sensitivity analyses were performed to examine the robustness of model findings.Results: Both SOF/LDV and SOF/VEL regimens were dominant to the pegIFN + RBV regimen by creating more QALYs and incurring less cost. SOF/LDV produced 0.542 more QALYs but cost $10,390 less than pegIFN + RBV. Relative to SOF/LDV, SOF/VEL had an ICUR of 168,239 $/QALY which did not meet the cost-effectiveness standard. Therefore SOF/LDV was the optimal strategy. These findings were robust to linear and random variations of model parameters. However, reducing the SOF/VEL price by 40% would make this regimen the most cost-effective option.Conclusions: SOF/LDV was found to be the most cost-effective treatment, and SOF/VEL was also economically dominant to pegIFN + RBV. These findings indicated that replacing pegIFN + RBV with DAA regimens could be a promising strategy.

The epistemic value of models has traditionally been approached from a representational perspective. This paper argues that the artifactual approach evades the problem of accounting for representation and better accommodates the modal dimension of modeling. From an artifactual perspective, models are viewed as erotetic vehicles constrained by their construction and available representational tools. The modal dimension of modeling is approached through two case studies. The first portrays mathematical modeling in economics, while the other discusses the modeling practice of synthetic biology, which exploits and combines models in various modes and media. Neither model intends to represent any actual target system. Rather, they are constructed to study possible mechanisms through the construction of a model system with built-in dependencies.

Introduction Published estimates of Alzheimer’s disease (AD) progression do not capture the full disease continuum. This study provides transition probabilities of individuals with amyloid-β (Aβ+) pathology across the disease continuum. Methods Patient-level longitudinal data from the National Alzheimer’s Coordinating Center were used to estimate progression rates. Progression rates through five clinically defined AD stages—asymptomatic, mild cognitive impairment due to AD (MCI-AD), mild AD dementia, moderate AD dementia, severe AD dementia—and death were measured as transition probabilities. Rates were assessed in “incident” patients who recently entered the stage, controlling for covariates. Transition probabilities were generated from multinomial logit regression models that predicted an individual’s health state as a function of health state at the previous visit and adjusted for time between initial and follow-up visits, age, sex, years of education, and concomitant symptomatic AD medications. Results Annual transition probabilities to more severe dementia stages for surviving incident Aβ+ patients were as follows: asymptomatic to MCI-AD, 40.8%; MCI-AD to mild AD dementia or worse, 21.8%; mild AD dementia to moderate AD dementia or worse, 35.9%; moderate AD dementia to severe AD dementia, 28.6%. Transition probabilities to less severe dementia stages were: 5.3% annual reversion from MCI-AD to asymptomatic, 3.0% mild AD dementia to MCI-AD, 1.8% moderate AD dementia to mild AD dementia, and 1.3% for severe AD dementia to moderate AD dementia. Conclusions These transition probabilities reflect the full continuum of AD progression in Aβ+ individuals and can be used to assess the impact of treatment on expected transitions. Supplementary Information The online version contains supplementary material available at 10.1007/s40120-021-00272-1.

There is consumer pressure on the US beef cattle industry to minimize antibiotic use (ABU) in order to aid in the global antimicrobial resistance mitigation efforts. Our objective was to estimate the economic costs of ABU constraints in a conceptual US integrated beef supply chain (IBSC) to aid the beef industry in mitigating the ever-increasing risk of antimicrobial resistance, by reducing their ABU. An IBSC network model was developed and differentiated into 37 different nodes of production. Each node could only raise a specific type of animals, differentiated based on the production technique and animal health status. The cost, as well as the weight gain coefficient, was estimated for each node, using an IBSC cost of production model. Linear programming solutions to this network model provided the least cost path of beef supply through the system, under various ABU constraints. The cost as well as weight gain coefficient of the 37 nodes, initial supply of 28.5 million calves weighing 0.65 million metric tons, and final demand of 16.14 million metric tons of slaughter-ready fed cattle were used as inputs/constraints to the three different linear programming scenarios, with different ABU constraints. Our first scenario, which placed no constraint on ABU, estimated that the minimum total economic cost to meet the final beef demand was $38.6 billion. The optimal solution was to use only the high health status calves for beef production. Because low health calves occur in the beef system, our second scenario required all the calves irrespective of their health status to be used, which increased the system cost to $41.5 billion. Thus, the value of only producing high health status calves is $2.9 billion. Our third scenario, which restricted feedlots from using antibiotics even for low health calves, incurred a total cost of $41.9 billion for antibiotic-free beef production. We concluded that the additional cost of $367 million for implementing antibiotic-free beef production is relatively low, ~0.90% of the minimum cost incurred for the conventional beef supply chain (model 2 cost of $41.5 billion). However, a much higher cost savings is obtained by producing only high health status calves.

International audience; Currently, under the conditions of permanent financial risks that hamper the sustainable economic growth in the financial sector, the development of evaluation and risk management methods both regulated by Basel II and III and others seem to be of special importance. The reputation risk is one of significant risks affecting reliability and credibility of commercial banks. The importance of reputation risk management and the quality of their assessment remain relevant as the probability of decrease in or loss of business reputation influences the financial results and the degree of customers', partners' and stakeholders' confidence. By means of imitating modeling based on Bayesian Networks and the fuzzy data analysis, the article characterizes the mechanism of reputation risk assessment and possible losses evaluation in banks by plotting normal and lognormal distribution functions. Monte-Carlo simulation is used to calculate the probability of losses caused by reputation risks. The degree of standardized histogram similarity is determined on the basis of the fuzzy data analysis applying Hamming distance method. The tree-like hierarchy based on the OWA-operator is used to aggregate the data with Fishburne's coefficients as the convolution scales. The mechanism takes into account the impact of criteria, such as return on equity, goodwill value, the risk assets ratio, the share of the productive assets in net assets, the efficiency ratio of interest bearing liabilities, the risk ratio of credit operations, the funding ratio and reliability index on the business reputation of the bank. The suggested methods and recommendations might be applied to develop the decision-making mechanism targeted at the implementation of reputation risk management system in commercial banks as well as to optimize risk management technologies.

International audience; Part of the French timber transformation industry suffers from difficulties to adapt to recent changes on global markets. This translates into net exports of raw wood and imports of transformed products, detrimental to both the trade balance and the local creation of wealth. At the same time, no consistent and homogeneous accounts for wood product production and consumption exist at this time. This article first aims at objectifying this situation by undertaking the first material flow analysis of the French forest-wood supply chain. We then evaluate the potential consequences of various scenarios of raw wood exports reduction policies, namely subsidies for consumption or transformation and taxation of exports, on both economic outcomes for the different actors and material flows. We thus provide an example of coupling material flow analysis with economic modeling in an attempt to move from the diagnostic phase to the assessment of possible actions within a decision-making perspective.

With their article, Grutters et al raise an important question: What do successful health technology assessments (HTAs) look like, and what is their real-world utility in decision-making? While many HTAs are published in peer-reviewed journals, many are considered proprietary and their attributes remain confidential, limiting researchers’ ability to answer these questions. Models for economic evaluations like cost-effectiveness analyses (CEAs) synthesize a wide range of evidence, are often statistically and mathematically sophisticated, and require untestable assumptions. As such, there is nearly universal agreement among researchers that enhancing transparency is an important issue in health economic modeling. However, the definition of transparency and guidelines for its implementation vary. Model registration combined with a linked database of model-based economic evaluations has been proposed as a solution, whereby registered models and their accompanying technical and nontechnical documentation are sourced into a single publicly-available repository, ideally in a standardized format to ensure consistent and complete representation of features, code, data sources, results, validation exercises, and policy recommendations. When such a repository is ultimately created, modelers will not have to reinvent the wheel for every new drug launched or new treatment pathway. These more open and transparent approaches will have substantial implications for model accuracy, reliability, and validity, improving trust and acceptance by healthcare decision-makers.

Background By design, existing scenario-based nutrition economics studies on the financial benefits of healthy dietary behaviors generally report uncertainty in inputs and wide ranges of outcome estimates. Objectives This modeling exercise aimed to establish precision in prediction of the potential healthcare cost savings that would follow a reduction in the incidence of cardiovascular disease (CVD) consistent with an increase in adherence to a Mediterranean-style diet (MedDiet). Design Using a Monte Carlo simulation model on a cost-of-illness analysis assessing MedDiet adherence, CVD incidence reduction, and healthcare cost savings in the United States and Canada, short- and long-term cost savings that are likely to accrue to the American and Canadian healthcare systems were estimated using 20 and 80% increases in MedDiet adherence scenarios. Results Increasing percentage of population adhering to a MedDiet by 20% beyond the current adherence level produced annual savings in CVD-related costs of US$8.2 billion (95% confidence interval [CI], $7.5-$8.8 billion) in the United States and Can$0.32 billion (95% CI, $0.29-$0.34 billion) in Canada. An 80% increase in adherence resulted in savings equal to US$31 billion (95% CI, $28.6-$33.3 billion) and Can$1.2 billion (95% CI, $1.11-$1.30 billion) in each respective country. Conclusion Computational techniques with stochastic parameter inputs, such as the Monte Carlo simulation, could be an effective way of incorporating variability of modeling parameters in nutrition economics studies for improved precision in estimating the monetary value of healthy eating habits.

Большое значение в части обеспечения социальной стабильности на территории отдельно взятого муниципалитета имеет финансовая поддержка зачастую убыточных «предприятий-символов», аккумулирующих не только уникальные трудовые ресурсы и основные фонды, но и ряд непрофильных активов, от функционирования которых зависит комфортное существование целых районов. Подобным предприятием в Екатеринбурге является ПАО «Уральский завод тяжелого машиностроения». Цель данного исследования – рассмотрение существующих методик оценки вероятности банкротства машиностроительных предприятий, находящихся под управлением институционального инвестора, и формулирование заключения о возможности адаптации методических подходов к специфике рассматриваемого объекта. С учетом особенностей влияния институционального инвестора охарактеризован объект исследования; проведена оценка вероятности банкротства ПАО «Уральский завод тяжелого машиностроения» на основе пяти наиболее популярных моделей; путем сопоставления темпов роста эффективности и производительности деятельности ПАО «Уральский завод тяжелого машиностроения» со среднеотраслевыми данными сделан вывод об адекватности моделей оценки вероятности банкротства; с учетом специфики деятельности рассматриваемого объекта выбрана наиболее адаптивная модель. Результаты исследования могут быть использованы руководством машиностроительных предприятий для объективной оценки степени финансового риска, связанного с устойчивым функционированием бизнеса, а также органами исполнительной власти различных уровней для целей определения направления административно-финансовой поддержки отрасли машиностроения и, в силу высокой социальной значимости отдельных предприятий, обеспечения социальной стабильности территории., The key role in providing social stability at the territory of any municipality is played by support of unprofitable “symbol” enterprises which accumulate unique labor resources and basic funds, and also secondary assets which promote comfortable existence of districts. This kind of enterprise in Yekaterinburg is JSC “Uralmashplant”. The goal of this investigation is a consideration of present methods of possible bankruptcy assessing of machine building enterprises under control of institutional investor and conclusion formation about adaptation possibility of methodical approaches to specificity of a considered object. Taking into account the features of institutional investor’s influence the object of investigation is characterized; the assessing of possible bankruptcy of JSC “Uralmashplant” is carried out on the base of five the most popular models; comparison of efficiency growth rates and activity productivity of JSC “Uralmashplant” with the average data the conclusion is made concerning adequate model of bankruptcy possibility assessing models; taking into account the specificity of this object the most adaptive model has been chosen. The investigation outcomes can be used by machine building enterprises administration for objective assessing of financial risk rates connected with stable business functioning, and also executive powers for defining ways of administrative and financial support of machine building branch due to high social significance of some enterprises and providing social stability of a territory.

В статье исследуются экономические явления с помощью применения математических методов. Более подробно рассмотрено математическое и экономическое моделирование, а также приведена классификация математических методов в экономической науке., The article investigates economic phenomena using mathematical methods. Mathematical and economic modeling is considered in more detail, as well as the classification of mathematical methods in Economics.

Contains fulltext : 215507.pdf (Publisher’s version ) (Open Access) BACKGROUND: To assess whether early health economic modeling helps to distinguish those healthcare innovations that are potentially cost-effective from those that are not potentially cost-effective. We will also study what information is retrieved from the health economic models to inform further development, research and implementation decisions. METHODS: We performed secondary analyses on an existing database of 32 health economic modeling assessments of 30 innovations, performed by our group. First, we explored whether the assessments could distinguish innovations with potential cost-effectiveness from innovations without potential cost-effectiveness. Second, we explored which recommendations were made regarding development, implementation and further research of the innovation. RESULTS: Of the 30 innovations, 1 (3%) was an idea that was not yet being developed and 14 (47%) were under development. Eight (27%) innovations had finished development, and another 7 (23%) innovations were on the market. Although all assessments showed that the innovation had the potential to become cost-effective, due to improved patient outcomes, cost savings or both, differences were found in the magnitude of the potential benefits, and the likelihood of reaching this potential. The assessments informed how the innovation could be further developed or positioned to maximize its cost-effectiveness, and informed further research. CONCLUSION: The early health economic assessments provided insight in the potential cost-effectiveness of an innovation in its intended context, and the associated uncertainty. None of the assessments resulted in a firm 'no-go' recommendation, but recommendations could be provided on further research and development in order to maximize value for money.

This article proposes a new economic modeling theoretical framework known as multidimensional real-time economic modeling (MRTE-Modeling). The model is an important tool that economists and educators can use to demonstrate the multidimensional aspects of economic behavior. MRTE-Modeling facilitates the analysis of a series of complex and dynamic economic problems that can affect market behavior from a multidimensional perspective. The proposed MRTE-Modeling framework is based on the uses of an alternative mathematical modeling framework, multidimensional graphical modeling approach, and computer algorithm and, thus, allows the possibility to transition from 2-dimensional economic dynamic modeling to multidimensional real-time economic modeling. Therefore, the main objective of using the proposed experimental model in the field of economics is to analyze different macroeconomic scenarios to monitor and provide a warning of possible unexpected economic failure(s). The proposed alternative experimental model is based on the application of Econographicology. Hence, our model is expected to offer policy makers and researchers new analytical tools to study the impact and trend of economic failures in the economy of any country from a new perspective.

Монополистическая конкуренция один из самых распространенных типов отраслевых рынков. В предыдущих работах авторов был разработан инструментарий моделирования рынков данного типа конкуренции, но не изучался случай изменения производительности труда в эффективных предприятиях. В работе анализируется влияние производительности труда предприятий на ценообразование, объемы производства продукции, уровень заработной платы и иные показатели. В спектр исследования попадает образование, получаемое населением для изменения квалификации труда. Доказывается, что рост эффективности рабочей силы способствует снижению цен в экономике и наращиванию объемов производимой продукции, росту уровня заработной платы квалифицированных рабочих и сокращению оплаты труда неквалифицированных, Monopolistic competition is one of the most common types of industrial markets. In previous works of the authors, a tool was developed for modeling markets of this type of competition, but the case of changes in labor productivity in efficient enterprises was not studied. The paper analyzes the influence of enterprise labor productivity on pricing, production volumes, wages and on other indicators. The range of research falls into the education received by the population for changing the qualification of labor. It is proved that the increase in the efficiency of the labor force contributes to the reduction of prices in the economy and the increase in the volume of output, the rise in the level of wages of skilled workers and a reduction in the wages of unskilled workers

Neosporosis in cattle herds is associated with large economic losses, with abortion being the only clinical sign perceptible to the producer. Losses are estimated at over one billion dollars worldwide. This study aimed to estimate the abortion risk difference in seropositive animals using specific data for dairy herds in Brazil. Differences in the risk of abortion between seropositive and seronegative animals were calculated through a meta-analysis of previous data from several Brazilian states, and an increase of 10.04% (0.091 to 0.118) in the specific risk was identified. This finding indicates that more than 474,000 abortions caused by neosporosis may be occurring only in dairy cattle herds in Brazil, causing a major economic loss in the milk production chain. The use of this specific measure for Brazilian herds opens the possibility of developing cost-benefit analysis for neosporosis in Brazil using data that are more reliable A neosporose está relacionada a grandes perdas econômicas em rebanhos bovinos, tendo o abortamento como único sinal clínico perceptível ao produtor, com prejuízos estimados em mais de um bilhão de dólares em todo o mundo. O presente trabalho teve como objetivo estimar a diferença no risco de aborto em animais soropositivos, especificamente com dados procedentes de rebanhos leiteiros do Brasil. A diferença do risco de aborto foi calculada através de uma meta-análise, com dados precedentes de vários estados brasileiros, tendo como resultado um aumento de 10,04% (0,091-0,118) no risco específico. Este resultado demonstra que podem estar ocorrendo mais de 474 mil abortamentos no Brasil, devido à neosporose, apenas em rebanhos bovinos leiteiros, causando grandes perdas econômicas para cadeia produtora de leite. A utilização dessa medida específica de rebanhos brasileiros abre a possibilidade de modelagem econômica do custo da doença no Brasil com dados mais fidedignos

The increasing economic interaction among various regions in China makes the construction of an interregional input–output table relevant for economic studies. This paper elaborates the model compilation procedure of the China Interregional Input–output model 2002. The key features of the model compilation include: (1) using representative commodities to estimate the interregional commodity flows of the primary industries; (2) adopting functions to estimate the decreasing interregional transportation of manufacturing sectors in relation to distance and (3) selecting appropriate indicators to estimate the interregional commodity flows of non-material sectors. This study is an initial attempt in interregional input–output modelling and might be helpful for economic studies at the levels of micro-regions.

The research is focused on efficiency assessment of economic cooperation in development of Arctic offshore oil and gas resources. The author developed an economic model based on cost-benefit analysis (CBA). CBA is used in some countries (EU, USA, Australia) as an analytic tool to make public policy decisions. CBA is based on the method of discounting cash flows associated with costs and benefits of public policy. It is assumed that all public goals are equally important inter alia, hence public bodies should opt for those initiatives that maximize public benefits for every dollar spent from the state budget. There are five stages of economic modeling: 1) the definition of public benefits and costs associated with the public initiative; 2) monetary valuation of costs and benefits; 3) the definition of discounting period and discounting rate; 4) the calculation of net present value of cash flows; 5) the comparison of initiatives' net present values. The model is built with a number of hypotheses assumed. It allows making evaluation of investments into the technology to decrease the cost of Arctic offshore oil and gas development. Moreover, the model has two scenarios describing a public policy to support technology development with international economic cooperation and without it. Under given hypotheses both scenarios return positive net present value of policies which proves that governmental initiative to support Arctic technology development is economically justified. Also the model sows that the scenario with international cooperation is more efficient from economic point of view. It is explained by two factors: the higher speed of technology transfer (due W international cooperation) and the opportunity to use financial leverage (attracting the funds from foreign partners). The model allows closing the existing scientific gap between the theory of CBA method and its practical use in public decision making.

We develop and analyze an economic model of remanufacturing to address two main research questions. First, we explore which market, cost, and product type conditions induce a profit-maximizing firm to be a remanufacturer, given a separate (secondary) remanufactured goods market. Such markets exist for consumer goods, where “newness” is a differentiating factor. Second, we describe what effect profitable remanufacturing has on the environment. Our stylized modeling framework for analyzing these issues incorporates three components: lease contracting, product design, and remanufacturing volume. To operationalize this framework, we model and solve for the optimal decisions of two firm types: a non-remanufacturer, which we call a traditional firm, and a remanufacturer, which we call a green firm. We describe conditions under which remanufacturing is (and is not) profitable, and demonstrate that under certain cost and market conditions remanufacturing has negative consequences for the environment. Our results have implications for firms and policy makers who would like to choose remanufacturing as a strategy to improve profitability and environmental performance, given the existence of conditions under which neither might occur.

This paper evaluates the prospect of a possible unification between People?s Republic of China (Mainland China) and Republic of China (Taiwan) from a multi-dimensional perspective which encompasses the political, social, economic, and technological dimensions. The underlying idea is to evaluate the possibility of a partial or total reunification between the two countries in a more comprehensive way than just assessing the economic costs and benefits. Our evaluation is based on the application of the GDRI-Model, which looks at unification and regional integration simultaneously from the political, economic, social and technological perspectives.

The paper discusses the topical issues of investment activities enhancement in the forest sector of the Russian economy by implementing the mechanism of priority investment projects in the field of forest exploitation – economic model of public-private partnership proposed by the forest owner (the State) for the private sector. The aim of the considered investment projects is the development of a timber-processing infrastructure, which is reliably provided with wood raw materials. It becomes possible to ensure certain preferences for businessmen that encourage them to invest money into the forest sector. Thus, the other objective is to develop recommendations for attracting investments into the forest sector of the Russian economy in the framework of priority investment projects. The paper analyzes a ten-year experience in the practice of applying priority investment projects in forest exploitation using an integrated approach to studying project management issues and method of comparison. The research identifies positive moments and a number of organizational and methodological shortcomings related to the development and implementation of investment projects in the forest sector of the Russian Federation. A number of areas contributing to the development of investment activities in forest exploitation is proposed.

We propose a new qualitative economic model based optimization approach to compose an optimal set of infrastructure service requests over a long-term period. The economic model is represented as a temporal CP-Net to capture the provider's dynamic business strategies in qualitative service provisions. The multidimensional qualitative preferences are indexed in a k-d tree to compute the preference ranking of a set of incoming requests. We propose a heuristic based sequential optimization process to select the most preferred composition without the knowledge of historical request patterns. Experimental results prove the feasibility of the proposed approach. Springer International Publishing Switzerland 2016. Scopus

Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2016, Thesis (PhD) -- İstanbul Technical University, Institute of Science and Technology, 2016, Parasal genişlemenin ekonomik aktivite üzerindeki etkisi, ampirik olarak gözlemlenen bir olgudur. Bununla birlikte, bu olgunun teorik açıklaması ve sonuçları, iktisat literatüründe süregelen bir tartışma olmuştur. Bu çalışmada, Enflasyonun Sistem Dinamiği Modeli olarak isimlendirilen dinamik bir dengesizlik modeli sunulmuştur. Bu modelin amacı, parasal ekonomik verilerle reel ekonomik veriler arasındaki dinamik ilişkinin teorik temellerini ve sonuçlarını, denge dışı bir yapıyla açıklamaktır. Sistem dinamiği, karmaşık sistemlerin dinamik davranışlarını açıklamaya ve analiz etmeye uygun bir modelleme ve simülasyon metodolojisidir. Sistem dinamiği modellerinde, modellenmek istenen sistemler, içerdikleri yapısal birimler ve bunlar arasındaki karşılıklı ilişkiler üzerinden tanımlanır. Bu karşılıklı ilişkiler zaman boyutunda tarif edilir, ve böylece sistemin bütününde doğrusal olmayan ve sezgilere aykırı davranışlar sergileyebilir. Tarihsel olarak, sistem dinamiği metodolojisi biyolojik sistemlerden sosyal sistemlere kadar pek çok alana uygulanmıştır. Ekonomik sistemler de, yapısal karmaşıklık ve öngörülemeyen davranışların gözlenmesinden dolayı, sistem dinamiği prensiplerine dayanan modeller geliştirmek için uygundur. Literatürde sistem dinamiği metodolojisinin ekonomik modellerde kullanımı hakkında çok fazla çalışma olsa da, parasal ve reel ekonomik veriler arasındaki ampirik ilişkilerin teorik yapısını açıklamaya yönelik olarak kurgulanmış ve tamamlanmış bir sistem dinamiği modeline rastlanmamıştır. Bu açıdan önerilen model, bu amaç ve kapsamdaki ilk örnek olma özelliğini taşımaktadır. Bu çalışmanın amacıyla ilişkili, ampirik olarak gözlenmiş bazı davranış kalıpları vardır. İlk olarak, parasal şokların ekonomik aktivite ve işsizlik oranı üzerinde belirgin bir etkisi olduğu görülmektedir. İkinci olarak, işsizlik oranı ile fiyat ve ücret enflasyonu arasında ters bir ilişki olduğu görülmektedir. Son olarak, enflasyon oranının parasal şoklara karşı direnç gösterdiği, ve ekonomik çevrimlerde büyüme oranlarına kıyasla bir faz gecikmesi oluştuğu gözlenmektedir. Bu davranış kalıpları birbirleriyle de ilişkilidir ve paranın reel ekonomik göstergelere farklı şekillerde etki ettiğini göstermektedir. Sistem dinamiği, karmaşık sistemlerin dinamik davranış kalıplarını açıklayabilme yeteneğinden dolayı, ampirik verilerdeki bahsedilen davranış kalıplarının yapısal ve teorik nedenlerini açıklama konusunda uygun bir araçtır. Bununla birlikte, günümüz ana akım iktisat teorileri, sistem dinamiği modellerinde kullanılmak için uygun değildir. Çünkü ana akım iktisat, rasyonel beklentiler ve katı denge varsayımlarına dayanmakta, bu varsayımlar da sistem dinamiği metodolojisinin yapısal gereklilikleriyle belirgin biçimde çelişmektedir. Sistem dinamiği modellerinde değişkenler, durum ve akış değişkenleri olarak tanımlanır. Akış değişkenleri, durum değişkenlerinin zamanla nasıl değiştiğini gösterirler. Bu akış değişkenlerinin model içerisinde belirlenmesi, durum değişkenlerinin kendilerinin yerine, değişimlerinin modellenmesini gerektirir. Değişimlerin modellenmesi durumunda ise durum değişkenlerinin, değişim boyunca denge değerlerinden farklı değerler alması kaçınılmazdır. Diğer bir deyişle, sistem dinamiği modelleri doğası gereği denge-dışı modeller olmak zorundadır. Ana akım iktisatta çok temel bir varsayım olan denge varsayımı ise, ekonomik sistemin sürekli olarak bir dengede olduğunu, denge dışı durumların da yalnızca değişimin maliyetli olmasından kaynaklı bilinçli bir tercih olarak seçilmiş durumlar olduğu için yine bir çeşit denge durumu olduğunu savunmaktadır. Diğer bir deyişle, günümüz ana akım iktisat modellerinde, ekonomik ajanların faydalarını kendi kısıtları içerisinde eniyilemeyen, dolayısıyla da bu ajanlar tarafından bilinçli bir tercih olarak gerçekleşmeyen hiç bir durumun var olmasına izin verilmez. Bundan dolayı, ana akım iktisat içerisinde ileri sürülen teoriler, sistem dinamiği prensipleri içerisinde kurgulanmaya uygun teoriler değildirler. Sistem dinamiği modellerinde kullanılmaya uygun teorik bilgilerin bulunabileceği alan, denge dışı teorilerin de yer aldığı Keynezyen ve Post-Keynezyen iktisat okullarıdır. Bu alandaki en etkileyici örnek, bir hidrolik analog bilgisayar olan Phillips Makinası'dır. Phillips Makinası, Bill Phillips tarafından 1949 yılında, London School of Economics'te tasarlanmıştır. Günümüzde bu makinanın benzerlerinden biri de, Istanbul Üniversitesi'nde bulunmaktadır. Phillips Makinası, Keynesyen bir denge dışı ekonomi modeline tekabül eden bir diferansiyel denklemler sistemini simüle etmektedir. Bu çalışmanın ilk bölümü, hem sistem dinamiği metodolojisinin ekonomik modellerde kullanılmasıyla ilgili etkileyici bir örnek olduğu için, hem de çalışmanın teorik altyapısıyla ilişkili olduğu için, Phillips Makinası'nın tanıtılmasına ayrılmıştır. Bu çalışmada, Phillips Makinası'nın iktisat tarihindeki ilk sistem dinamiği modeli olduğu ileri sürülmüştür. Phillips Makinası'nın tanıtıldığı giriş bölümünün ardından, denge kavramı üzerine birbirinden farklı ve uyumsuz iktisadi görüşler hakkında bir tartışma bölümü verilmiştir. İlk kez bu çalışmada, denge kavramı ve bununla ilişkili konular hakkında yapılan tartışmalar, 'Zaman İhtilafı' olarak olarak tanımlanmıştır. Bu tartışma bölümünün ardından, sistem dinamiği metodolojisinin tanıtıldığı ve ilgili literatür taramasının verildiği bölüm gelmektedir. Ardından enflasyon literatürü, tarihsel bir perspektif eşliğinde verilmiş, ve konu hakkındaki önemli noktalara değinilmiştir. Enflasyon konusunun anlatıldığı bölümden sonra, model açıklamasının yapıldığı bölüm verilmiştir. Bu bölümde, sunulan sistem dinamiği modeli, alt modeller halinde gösterilmiş, ve açıklanmıştır. Buna göre modelde altı tane alt model vardır. Para alt modeli, Phillips Makinası'nın simüle ettiği ekonomik model baz alınarak tasarlanmıştır. Bu alt modelde, yaratılan gelirin para formunda devir daim etmesi açıklanmış, bu şekilde parasal talebin nasıl oluştuğu gösterilmiştir. Ürün alt modelinde, reel talep ve arz arasındaki ilişki tanımlanmıştır. Arz ve talep değişkenleri birer akış şeklinde ayrı ayrı gösterilmiştir. Bu iki akış değişkeninin sürekli birbirine eşit olma zorunluluğunu ortadan kaldırmak üzere, bir envanter değişkeni tanımlanmıştır. Buna göre toplam arz envanteri artıran, toplam talep de envanteri azaltan bir akış değişkenidir. Fiyat alt modelinde, ekonomideki genel fiyat düzeyi belirlenir. Arz edilen miktar tarafından belirlenen birim maliyet ve ortalama kar marjı üzerinden fiyat düzeyinin hedeflenen değeri belirlenir, ve fiyat düzeyi bu hedef değere belirli bir hızda yaklaşır. Fiyat düzenleme süresi, ekonomideki ürün fiyat etiketlerinin ortalama değişme süresini ifade eder, ve fiyat düzeyinin hedef değerine ne hızla yaklaştığını belirleyen parametredir. İşgücü alt modelinde, toplam çalışan ve işsiz işgücü birer durum değişkeni olarak tanımlanmıştır. Bu durum değişkenleri arasındaki akışlar, arz-talep ilişkisi üzerinden tarif edilmekte, ve işsizlik oranını belirlemektedir. Ücret alt modelinde de, işgücü piyasasındaki değişiklikler ve işsizlik oranının, ücret düzeyini nasıl etkilediği modellenmiştir. Buna göre, işsizlik oranı düşük olduğunda ve düşmekte iken ücret düzeyi yükselmekte, yüksek olduğunda ve yükselmekte iken de ücret düzeyi düşmektedir. Son olarak yatırım alt modeli tanımlanmıştır. Yatırım alt modelinde, yatırımların sermaye verimliliği ve talep tahmininden nasıl etkilendiği modellenmiştir. Bu alt modelde belirlenen hedeflenen parasal yatırım miktarı, ürün alt modelinde parasal talebin belirlenmesinde girdi olarak kullanılmaktadır. Önerilen sistem dinamiği modeli, iki farklı şok uygulayarak test edilmiştir. İlk olarak sisteme tek bir defaya mahsus olmak üzere para enjekte edilmiş, ve modelin davranışı izlenmiştir. Ardından sisteme sabit bir oranda para enjekte edilmiştir. Simülasyon sonuçlarına göre, model ampirik gözlemlerdeki davranış kalıplarına benzer bir davranış sergilemektedir. Örneğin işsizlik oranı, ücret enflasyonu, fiyat enflasyonu, beklenmeyen enflasyon ve reel ücret düzeyi ile ters orantılı bir davranış sergilemektedir. Saçılım diyagramlarının özellikleri, ampirik verilerle düzenlenen grafikler ile benzerlik göstermektedir. Bununla birlikte önerilen model, enflasyondaki süreklilik davranışı ve enflasyon-büyüme oranları arasındaki faz farkını da yaratabilmektedir. Model, kullanılan parametre kümesine göre değişkenlik gösteren limit çevrimi oluşturmaktadır. Bu çevrimler geleneksel iktisadi dalgalanmaların temel özelliklerini sergilemektedir. Makul parametre değerlerinde, çevrimlerin ortalama şiddeti %5, ve ortalama süresi 4 yıl olarak gerçekleşmektedir. Modelin güvenirliğini belirlemek için bazı testler uygulanmıştır. Yapısal onay testinde, modeldeki her bir eşitlik ayrı ayrı ele alınmış, ve ampirik ve teorik bilgilerle ne ölçüde uyumlu olduğu irdelenmiştir. Parametre onay testinde, modelde kullanılan parametrelerin ampirik verilere kıyasla mantıklı, teorik olarak da uyumlu olup olmadıkları irdelenmiştir. Direkt aşırı durum testinde, modeldeki formülasyonlar varsayımsal olarak aşırı durumlara uyarlanmış, ve analitik sonuçlarla gerçek hayatta aşırı durumlarda gerçekleşmesini öngördüğümüz durumlar kıyaslanmıştır. Boyutsal tutarlılık testinde, değişkenlerin birimlerinin anlamlı olup olmadığı, gerçek hayatta neye tekabül ettiği, ve eşitliklerdeki birimlerin tutarlı sonuçlar verip vermediği irdelenmiştir. Parametre hassaslığı testinde, modelin davranışının farklı parametre değerlerine göre ne ölçüde hassas olduğu analiz edilmiştir. Aşırı durum testinde, modelin davranışı gerçek hayatta karşılaşılmayan fakat teorik olarak mümkün bazı aşırı durumlar için test edilmiştir. Son olarak, davranış güvenirliği testinde, simülasyon sonuçlarının ampirik gözlemlerle uyumlu olup olmadığı tartışılmıştır. Modelin sergilediği davranışlara bakıldığında işgücü piyasasının, ekonomik değişkenliğin ana kaynağı olduğu söylenebilir. Benzer şekilde davranış hassaslık analizinin sonuçlarına bakıldığında, davranış kalıplarının bazı parametre değerlerine karşı belirgin biçimde hassaslık gösterdiği, ve çevrimsel davranışı etkileyen ana unsurun is¸gücü piyasası olduğu görülmektedir. Buna göre, eğer ücret düzeylerinin düzenleme süreleri kısalırsa, iktisadi sistemin bütününde istikrarsız davranış gözlenmektedir. Bu sebeple politika yapıcılara, ekonomik istikrar için, ücret düzeylerindeki ani değişimleri kontrol edecek regülasyonlar önerilmektedir. Paranın ekonomik aktivite üzerindeki etkisini açıklamayı amaçlayan sistem dinamiği modeli, bu çalışmanın temel bilimsel katkısını oluşturmaktadır. Bununla birlikte, önerilen modelin davranışları ve bunların teorik çıkarımları, araştırmacılar ve politika yapıcılar için önemli bilgiler sunmaktadır. Son olarak, bu çalışmada denge ve zaman ihtilafı hakkında yapılan teorik tartışmalar, iktisat ve sistem dinamiği alanlarındaki teorik araştırmalara katkı sunacaktır., Effect of money on output is an empirically observed phenomenon. Yet, the theoretical foundations and implications of this phenomenon is a debate in economics. In this study, System Dynamics Model of Inflation is developed in order to explain these foundations and implications based on a disequilibrium economic framework. System dynamics is a modeling and simulation methodology which is suitable for analyzing the dynamic behavior of complex systems. In system dynamics models, systems are defined as the structural components and their interrelations. These interrelations are defined on time dimension, thus the whole system may show non-linear and unintuitive behavior. Historically, system dynamics methodology is applied in various areas, from biological systems to social systems. Economics is also a suitable area to apply system dynamics principles for modeling, because of the complexity of the economic system structure, and the counter-intuitive behavioral observations in the system. Although there are many studies in the literature about the usage of this methodology for economic modeling, a complete system dynamics model could not be found which aims to explain the theoretical nature of the empirical relation between monetary and real economic variables. There are several empirical observations related to the scope of this study. First, a monetary shock appears to affect economic activity and unemployment rate. This effect sustains and accumulates for more than a year. Secondly, there is a negative relation between unemployment rate and inflation rates. Finally, inflation is persistent to monetary shocks and there is a phase lag for inflation in the business cycle. These behavior patterns are all related and show that money has different effects on the real economic indicators. Due to its ability to explain dynamic behavior of complex systems, system dynamics methodology is suitable to explore the structural reasons of these empirical regularities. However, the currently mainstream new-consensus model is not applicable in system dynamics models. Mainstream economic view is based on rational expectations and strict equilibrium assumptions, which conflicts the fundamentals of the system dynamics methodology. Theoretical knowledge for a suitable framework can be found in the disequilibrium theories of Keynesian and Post-Keynesian schools of thought. A remarkable example is Phillips Machine, a hydraulic analog computer built by Bill Phillips in 1949, in London School of Economics. It simulates a set of differential equations of a Keynesian disequilibrium economic model. The beginning of this study is dedicated to Phillips Machine, because it is an impressive example of using system dynamics methodology in economic modeling, and it is closely related with the purpose of this study. In this study, this machine is argued to be the first system dynamics model in the history of economics. The study follows with a discussion chapter about different economic views and incompatibilities on the concept of equilibrium. For the first time, this historical debate is entitled as 'Time Controversy'. This discussion chapter is followed by introductory chapter, dedicated to introduce the system dynamics methodology. After that, literature review of inflation is given from a historical perspective. Finally, description of the proposed model is given, model behavior is analyzed, and validation tests are conducted. System Dynamics Model of Inflation includes six sectors, or sub-models. Money sector explains the determination of demand-side by the circular flow of income. In the goods sector, supply-side is formulated and both sides are linked in real terms. In the price sector, pricing behavior of firms is explained. In the labor sector, employment dynamics are captured. In the wage sector, wage determination is explained by the feedback from labor sector. Finally, in the investment, investment decisions are described. The proposed model is tested for two types of monetary shock, which are named as money shock and inflation shock. The simulation results show that, the model is able to generate the related behavior patterns similar to empirical observations. Accordingly, unemployment rate is inversely related with wage inflation, price inflation, unexpected inflation and real wage level. The simulated scatter diagrams share some properties with the empirical observations. Moreover, the model is able to generate the persistent behavior of inflation, and the phase lag between inflation and growth rate. Depending on the parameter set, the model may generate limit cycles. These cycles share the behavioral properties of the conventional business cycles. The amplitude of this limit cycle is around 5% and the duration of cycles is approximately 4 years, for reasonable parameters. For building confidence on the proposed model, some validation tests are applied. In the structure confirmation test, each equation in the model is evaluated for its relevance to empirical and theoretical knowledge. In the parameter confirmation test, model parameters are questioned for being empirically reasonable and theoretically consistent. In the direct extreme-condition test, model equations are hypothetically forced to extreme conditions, in order to compare the analytical results with the real life anticipations for these extreme conditions. In the dimensional consistency test, the units of the variables are questioned to be meaningful and consistent with each other. In the integration error test, the sensitivity of model behavior to the simulation step is considered and the accuracy of the integration process is questioned for validation. In the extreme condition test, model behavior is analyzed for extreme condition scenarios, which are not likely to observe in real life but theoretically possible. In the parameter sensitivity test, the sensitivity of model behavior to different parameter sets are analyzed. Finally, in the behavioral validation test, the simulation results are discussed to be consistent with empirical observations. Model behavior shows that, labor market is the main source of economic instability. Likewise, sensitivity analysis show that, the behavior is significantly sensitive for some parameters, and the cyclic behavior is mainly the result of labor market conditions. Specifically, when wage rates adjusts easily, the overall economic system become more unstable. As a result, governmental controls and regulations for wage determination are argued to be a reasonable policy for economic stability. The proposed model in this study is the first system dynamics economic model which aims to explain the effect of money on output, and is the main contribution of this study. Other than that, the theoretical implications of the model behavior are also important for researchers and policy makers. Finally, the theoretical discussions about equilibrium and time controversy are scientifically valuable for the theoretical research in economics and system dynamics., Doktora, PhD

Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO) recently completed a major study investigating the value of distributed energy (DE; collectively demand management, energy efficiency and distributed generation) technologies for reducing greenhouse gas emissions from Australia’s energy sector (CSIRO, 2009). This comprehensive report covered potential economic, environmental, technical, social, policy and regulatory impacts that could result from the wide scale adoption of these technologies. In this paper we highlight the economic findings from the study. Partial Equilibrium modeling of the stationary and transport sectors found that Australia could achieve a present value welfare gain of around $130 billion when operating under a 450 ppm carbon reduction trajectory through to 2050. Modeling also suggests that reduced volatility in the spot market could decrease average prices by up to 12% in 2030 and 65% in 2050 by using local resources to better cater for an evolving supply-demand imbalance. Further modeling suggests that even a small amount of distributed generation located within a distribution network has the potential to significantly alter electricity prices by changing the merit order of dispatch in an electricity spot market. Changes to the dispatch relative to a base case can have both positive and negative effects on network losses.

[EN] In decision-making processes, reliability and risk aversion play a decisive role. This paper presents a framework for stochastic optimization of control strategies for groundwater nitrate pollution from agriculture under hydraulic conductivity uncertainty. The main goal is to analyze the influence of uncertainty in the physical parameters of a heterogeneous groundwater diffuse pollution problem on the results of management strategies, and to introduce methods that integrate uncertainty and reliability in order to obtain strategies of spatial allocation of fertilizer use in agriculture. A hydro-economic modeling approach is used for obtaining the allocation of fertilizer reduction that complies with the maximum permissible concentration in groundwater while minimizes agricultural income losses. The model is based upon nonlinear programming and groundwater flow and mass transport numerical simulation, condensed on a pollutant concentration response matrix. The effects of the hydraulic conductivity uncertainty on the allocation of nitrogen reduction among agriculture pollution sources are analyzed using four formulations: Monte Carlo simulation with pre-assumed parameter field, Monte Carlo optimization, stacking management, and mixed-integer stochastic model with predefined reliability. The formulations were tested in an illustrative example for 100 hydraulic conductivity realizations with different variance. The results show a high probability of not meeting the groundwater quality standards when deriving a policy from just a deterministic analysis. To increase the reliability several realizations can be optimized at the same time. By using a mixed-integer stochastic formulation, the desired reliability level of the strategy can be fixed in advance. The approach allows deriving the trade-offs between the reliability of meeting the standard and the net benefits from agricultural production. In a risk-averse decision making, not only the reliability of meeting the standards counts, but also the probability distribution of the maximum pollutant concentrations. A sensitivity analysis was carried out to assess the influence of the variance of the hydraulic conductivity fields on the strategies. The results show that the larger the variance, the greater the range of maximum nitrate concentrations and the worst case (or maximum value) that could be reached for the same level of reliability. © 2011 Elsevier Ltd., The study has been partially supported by the European Community 7th Framework Project GENESIS (226536) on groundwater systems and from the Plan Nacional I+D+I 2008-2011 of the Spanish Ministry of Science and Innovation (subprojects CGL2009-13238-C02-01 and CGL2009-13238-C02-02). The authors thank the anonymous reviewers for their suggestions for improving the paper.

This paper provides a detailed, cross-model analysis and discussion of the implications of carbon tax scenarios on changes in sectoral output, energy production and consumption and the competitiveness of the United States’ economy. Our analysis focuses on the broad patterns apparent across models in both qualitative and quantitative terms at the sector level, with a focus on energy-intensive, trade-exposed sectors. We identify how variations in carbon tax trajectories and different options for using the revenue from the tax drive these results.

In fund raising management the employment of a decision support system is crucial for optimising the results of fund raising campaigns. However, the current tools based on database technology are not able to suggest suitable fund raising strategies and the support to the fund raiser is limited to give general indications in relation to specific claims. In this paper, we present a fuzzy knowledge-based decision support system, which is able to individuate promising fund raising strategies for a given campaign. The system uses a knowledge based description of the campaign features and of the donors profiles and integrates these data with two models for strategies and historical information evaluation, rules of thumb suggested by experts in the field, and recent econometric studies. The system provides a ranking of suitable strategies using fuzzy evaluations. Experimental results confirm the applicability of the proposed approach in real contexts, providing significant insight into the improvement of campaigns performances.

International audience; Economic modeling assumes, for the most part, that agents are Bayesian, that is, that they entertain probabilistic beliefs, objective or subjective, regarding any event in question. We argue that the formation of such beliefs calls for a deeper examination and for explicit modeling. Models of belief formation may enhance our understanding of the probabilistic beliefs when these exist, and may also help us characterize situations in which entertaining such beliefs is neither realistic nor necessarily rational.

Based on the similarity of properties of photons and money, and on the formula for the density of distribution of photon gas by energies, the corresponding mathematical formula for distribution of annual income per capita is obtained. Application of this formula for the data analysis reveals several independent groups of population with different average levels of their income. In particular four main groups of population contribute to the distribution of income in the economy of the USA.

[EN] In the last decade, there has been an increase in demand for biofuels, fostered by public policies. In the European Union, Directive 2009/28/EC (RED) establishes a 10% target for renewable energy use in the transport sector by 2020, in order to reduce overall greenhouse gas (GHG) emissions. In view of the land use change (LUC) that has recently occurred on a global scale as a consequence of bioenergy expansion, environmental considerations are more frequently incorporated into biofuel policies in order to promote only those biofuels delivering substantial GHG savings. The aim of the present thesis has been to analyze the environmental effects of the introduction of biodiesel for transport in the context of Spain, by applying different methodologies under a life cycle perspective, in order to address controversial issues, such as indirect LUC. First of all, the environmental and economic benefits brought about by an integrated process for waste management have been analyzed; biodiesel is obtained from the treatment of used cooking oil (UCO). The evaluation of the environmental performance has been carried out by means of the Life Cycle Assessment (LCA) methodology, while the financial assessment has been performed by applying a Life Cycle Costing (LCC). Both methodologies are based on a holistic approach and are crucial for a more thorough understanding of the sustainability of the proposed system. The combined study shows that the process has the potential to cause significant environmental benefits (subject to methodological assumptions), but this comes at the expense of the profits generated when the analysis is carried out from a municipal point of view. LCA has been subsequently applied to different systems for biodiesel production under a consequential approach, as the only way to measure indirect effects. There are different methodologies to carry out a consequential LCA, and all of them require the application of economic concepts. The first one consists of performing system expansion in order to include the additional functions provided by the co-products, since indirect effects arise from co-product interactions with other life cycles in the international market. This has allowed for the biodiesel domestically produced from UCO to be compared with the soybean biodiesel imported from Argentina. Furthermore, a mathematical programming model has been proposed based on the biodiesel sector's nameplate capacity in Spain. Its aim is to determine the optimal feedstock mix according to economic criteria, in order to meet the target demand for 2020; the biodiesel resulting from the mix must also fulfill the environmental requirements in the RED. The model allows for an LCA to be simultaneously carried out, in order to calculate the emissions associated with each production pathway. Indirect emissions from LUC in the Spanish agriculture can also be estimated. Finally, a general equilibrium model has been used to analyze the global environmental consequences, in terms of GHG emissions and LUC, of increasing the demand for biodiesel in the EU to meet the RED targets, in combination with recent anti-dumping measures on biodiesel imports from some specific countries. The outcomes from these studies have allowed for emission factors to be determined for different biodiesel production pathways in the Spanish market. Not only global warming has been taken into account but also other impact categories, which may be equally critical. In addition, pros and cons of the methodologies applied have been identified, depending on the goal and scope of the study; they should be applied in a complementary manner for a better understanding of the global phenomenon of bioenergy, increasing the confidence in GHG emission results. Reducing uncertainty in LUC estimates is crucial to enhance the applicability of future biofuel policies., [ES] La demanda de biocombustibles ha aumentado progresivamente en los últimos años, fomentada por políticas públicas. En la Unión Europea, la Directiva 2009/28/EC (RED) establece un objetivo del 10% para el uso de energías renovables en el sector del transporte en 2020, con tal de reducir los gases de efecto invernadero (GEI). Ante la evidencia del cambio en el uso del suelo (CUS) a escala global a consecuencia del auge de los biocombustibles, se han incorporado consideraciones ambientales para promover únicamente aquellos biocarburantes que causen un ahorro sustancial de GEI. El objetivo de la presente tesis ha sido analizar los efectos ambientales de la introducción de biodiesel en el contexto español, aplicando distintas metodologías bajo una perspectiva del ciclo de vida, con el fin de abordar cuestiones controvertidas como el CUS indirecto. En primer lugar, se han evaluado los beneficios ambientales y económicos derivados de un proceso integrado de tratamiento de residuos donde se produce biodiesel a partir de aceite de cocina usado (ACU). La evaluación ambiental se ha realizado mediante la metodología de Análisis de Ciclo de Vida (ACV), mientras que la evaluación financiera se ha llevado a cabo mediante el cálculo del Coste del Ciclo de Vida. Ambas metodologías comparten el mismo enfoque holístico y son esenciales para una comprensión más completa de la sostenibilidad del sistema propuesto. El análisis combinado revela que, si bien éste presenta el potencial de generar importantes beneficios ambientales (sujeto a supuestos metodológicos), esto ocurre a costa del beneficio económico cuando el análisis se hace desde el punto de vista municipal. A continuación, se ha aplicado el ACV a distintos sistemas de producción de biodiesel bajo un enfoque consecuencial, como la única forma de estimar el CUS indirecto. Existen diferentes metodologías para la realización de un ACV consecuencial y todas ellas requieren la aplicación de conceptos económicos. La primera consiste en aplicar la expansión del sistema para incluir las funciones adicionales desempeñadas por los coproductos, ya que los efectos indirectos surgen de las interacciones de éstos con otros ciclos de vida en el mercado internacional. Ello ha permitido comparar la producción de biodiesel de ACU frente a la importación de biodiesel de soja de Argentina. Se ha propuesto también un modelo de programación matemática basado en la capacidad nominal del sector del biodiesel en España. Su objetivo es determinar la combinación de materias primas óptima, desde el punto de vista económico, para cumplir con de la demanda proyectada para 2020 pero que cumpla a su vez con las exigencias ambientales de la RED. El modelo incorpora un módulo para realizar un ACV de forma simultánea, que permite estimar las emisiones asociadas a las distintas vías de obtención de materias primas. Se pueden calcular incluso las emisiones indirectas por CUS en la agricultura española. Finalmente, se ha aplicado un modelo de equilibrio general para el análisis de las consecuencias ambientales globales (en términos de emisiones de GEI y CUS) de un aumento en la demanda de biodiesel en la UE según la RED, en combinación con las recientes medidas arancelarias sobre las importaciones de determinados países. Todo ello ha permitido calcular factores de emisión para diferentes alternativas de producción de biodiesel destinado al mercado español, no sólo en relación al calentamiento global sino también a otras categorías de impacto que pueden ser igualmente críticas. Además, se han identificado ventajas e inconvenientes de las metodologías aplicadas, dependiendo del objetivo y el alcance de estudio; lo ideal es aplicarlas de forma complementaria para una mayor comprensión del fenómeno global de la bioenergía, contribuyendo a una mayor solidez en los resultados de GEI. Reducir la incertidumbre en las estimaciones de CUS es fundamental para asegurar la a, [CAT] La demanda de biocombustibles ha augmentat progressivament els darrers anys, fomentada per polítiques públiques. En la Unió Europea, la Directiva 2009/28/EC (RED) estableix un objectiu del 10% per a l'ús d'energies renovables en el sector del transport en 2020, amb l'objectiu de reduir els gasos d'efecte hivernacle (GEH). Davant l'evidència del canvi en l'ús del sòl (CUS) a escala global a conseqüència de l'auge dels biocombustibles, s'han incorporat consideracions ambientals per promoure únicament aquells biocarburants que causen un estalvi substancial de GEH. L'objectiu de la present tesi ha estat analitzar els efectes ambientals de la introducció de biodièsel en el context espanyol, mitjançant l'aplicació de diferents metodologies sota una perspectiva del cicle de vida, amb la finalitat d'abordar qüestions tan controvertides com el CUS indirecte. En primer lloc, s'han avaluat els beneficis ambientals i econòmics derivats d'un procés integrat de tractament de residus on es produeix biodièsel a partir d'oli de cuina usat (OCU). L'avaluació ambiental s'ha realitzat mitjançant la metodologia d'Anàlisi de Cicle de Vida (ACV), mentre que l'avaluació financera s'ha dut a terme mitjançant el càlcul del Cost del Cicle de Vida. Ambdues metodologies comparteixen el mateix enfocament holístic i són essencials per a una comprensió més completa de la sostenibilitat del sistema proposat. L'anàlisi combinada revela que, si bé aquest presenta el potencial de generar importants beneficis ambientals (subjecte a supòsits metodològics), això ocorre a costa del benefici econòmic quan l'anàlisi es fa des del punt de vista municipal. A continuació, s'ha aplicat l'ACV a diferents sistemes de producció de biodièsel sota un enfocament conseqüencial, com l'única forma d'estimar el CUS indirecte. Existeixen diferents metodologies per a la realització d'un ACV conseqüencial i totes elles requereixen l'aplicació de conceptes econòmics. La primera consisteix a aplicar l'expansió del sistema per incloure les funcions addicionals exercides pels coproductes, ja que els efectes indirectes sorgeixen de les interaccions d'aquests amb altres cicles de vida al mercat internacional. Això ha permès comparar la producció de biodièsel d'OCU amb la importació de biodièsel de soia de l'Argentina. S'ha proposat també un model de programació matemàtica basat en la capacitat nominal del sector del biodièsel a Espanya. El seu objectiu és determinar la combinació òptima de matèries primeres, des del punt de vista econòmic, per complir amb de la demanda projectada per 2020 però que complisca al seu torn amb les exigències ambientals de la RED. El model incorpora un mòdul per realitzar un ACV de forma simultània, el qual permet estimar les emissions associades a les diferents vies d'obtenció de matèries primeres. Es poden calcular fins i tot les emissions indirectes per CUS en l'agricultura espanyola. Finalment, s'ha aplicat un model d'equilibri general per a l'anàlisi de les conseqüències ambientals globals (en termes d'emissions de GEH i CUS) d'un augment en la demanda de biodièsel en la UE segons la RED, en combinació amb les mesures aranzelàries recents sobre les importacions des de determinats països. Tot això ha permès calcular factors d'emissió per a diferents alternatives de producció de biodièsel destinat al mercat espanyol, no només en relació a l'escalfament global sinó també a altres categories d'impacte que poden ser igualment crítiques. A més, s'han identificat avantatges i inconvenients de les metodologies aplicades, depenent de l'objectiu i l'abast d'estudi; l'ideal és aplicar-les de forma complementària per a una major comprensió del fenomen global de la bioenergia, per contribuir a una major solidesa en els resultats de GEH. Reduir la incertesa en les estimacions de CUS és fonamental per assegurar l'aplicabilitat de les polítiques de biocombustibles en el futur., Escobar Lanzuela, N. (2015). Contribution to the environmental impact assessment of biodiesel in the context of Spain [Tesis doctoral]. Editorial Universitat Politècnica de València. doi:10.4995/Thesis/10251/52027., TESIS

International audience; This chapter reviews existing long term water demand forecasting methodologies. Based on an extensive literature review, it shows that the domain has benefited from contributions by economists, engineers and system modelers, producing a wide range of tools, many of which have been tested and adopted by practitioners. It illustrates, via three detailed case studies in the USA, the UK and Australia, how different tools can be used depending on the regulatory context, the water scarcity level, the geographic scale at which they are deployed and the technical background of water utilities and their consultants. The chapter reviews how practitioners address three main challenges, namely the integration of land use planning with demand forecasting; accounting for climate change; and dealing with forecast uncertainty. It concludes with a discussion of research perspectives in that domain.

International audience; This book has its origins in a meeting of Australian and French researchers inMontpellier in June 2011, a meeting that was preceded by an approach by FritzSchmul at Springer to Quentin Grafton to write a book on urban water. On theAustralian side, the French–Australian collaboration was initiated by KatherineDaniell and Quentin Grafton from the Australian National University, and on theFrench side, by Olivier Barreteau and Nils Ferrand from IRSTEA and the Embassyof France in Australia. The vision of the principals was to link across disciplines,distance, and language to develop meaningful collaborations and insights that wouldotherwise not be possible.Several research initiatives grew out of the 2011 workshop and have led tovarious outcomes and outputs. One of the outcomes is this volume on urbanwater in transition. The book initially began as a series of ideas in a breakoutsession chaired by Quentin Grafton at the Montpellier workshop, and then, afterthe event, was developed further by all the editors. As editors, our goal has beenbroad: to develop a single framework, applicable to both rich countries anddeveloping and emerging economies, for understanding and acting on urbanwater issues, despite the manifold shifts and transitions underway. We wanted tounderstand how urban water is valued, supplied, managed, delivered, consumed,and treated.This volume is the outcome of a 3-year gestation and much hard work followingthe 2011 workshop. All the editors realized that the original group in Montpellierdid not have suffi cient diversity of knowledge and experience to deliver on what wasintended to be a book on global urban water. Consequently, many additional experts,practitioners, and researchers were invited to contribute, and almost all accepted theinvitation.

This research paper presents four alternative experimental models for monitoring economic failures. These models include the national production function (NP-Function), the multi-level trade creation and trade diversion analytical framework, the mega-economic structures vulnerability analysis (MSV-Analysis), and the mega-economic surface interactive system. The main objective behind the proposed experimental models in economics is to analyze different macroeconomic scenarios in monitoring and warning of possible unexpected economic failure(s) under the use of a new mathematical framework and the application of multidimensional graphs. The proposed alternative experimental models are based on the application of Econographicology. Hence, our models are expected to offer policy-makers and researchers new analytical tools to study the im pact and trend of economic failures in the economy of any country from a new perspective. Finally, we suggest the application of three new concepts in the study of economic failures such as Omnia Mobilis (everything is moving), the global structural imbalance principle, and the dynamic imbalance state. Therefore, our findings would certainly help both policy makers and researchers to implement and execute appropriate policies to develop their economies and to protect them from unwanted situations.

Economic grounds of formation of the production and territorial structure of the Russian fuel-and-energy complex are considered, characteristics of the centralized planning models of the power supply systems in the USSR economy are studied in view of various concepts of economic regions. Issues of transformation of the mechanisms of spatial decisions’ elaboration in the Russian power sector during crisis and post-crisis periods are discussed

This thesis sought to ascertain the feasibility of population-level liver cancer prevention in people with chronic hepatitis B (CHB) infection. This followed on from our group’s economic modelling work, showing that improved CHB management delivers better and more cost-effective hepatocellular cancer (HCC) outcomes, compared to HCC screening. Establishing the B Positive program in South West Sydney allowed us to test a primary care-based HCC prevention intervention in a high CHB prevalence area. We found that local General Practitioners (GPs) could accommodate additional appointments for CHB management, but not the local specialist services. Consequently we developed a CHB management algorithm stratifying patients by level of HCC risk, with high-risk patients referred for antiviral treatment and primary care-level management for the rest. As antiviral treatments accounts for 75% of program costs, lowering drug costs is critical to make HCC prevention affordable in low-resource settings. We addressed local health practitioners’ information needs about CHB and offered additional practice support. We established a CHB disease Registry, currently enrolling approximately 25% of our target population, with antiviral treatment uptake 6-fold higher than the national average. This thesis demonstrated that clinical-Public Health collaborations can deliver successful HCC prevention at primary care level, endorsed by the local community.

In economics it is common to distinguish between different time horizons (i.e. short run, medium run, and long run). Engle (1974) proposed combining the discrete Fourier transform with a band spectrum regression to estimate models that separates between different time horizons. In this paper we discuss possibilities and challenges using the maximal overlap discrete wavelet transform instead of the Fourier transform when estimating band spectrum regressions.

Theories of regional integration typically analyze the regional integration process from the perspective of a single discipline, usually economics. However, such one-dimensional analytical frameworks cannot fully capture the richness and complexity of the inherently multi-dimensional regional integration process. To address the problem, we propose the regional integration evaluation (RIE) methodology which is based on four dimensions of development – economic, political, social and technological. The central idea behind the RIE methodology is that regional development promotes regional integration. Our RIE methodology differs from the existing literature in that it is based on a more comprehensive definition of development than just economic development. Our definition of a region's development incorporates the development levels of all regional countries as well as differences in development levels among regional countries. We apply the RIE methodology to assess the regional development and hence integration prospects of NAFTA, ASEAN, MERCOSUR and EU.

This paper uses economic modeling to examine the controversial role that Group Purchasing Organizations (GPOs) play in the supply chains for healthcare products. Among the controversies, perhaps the most fundamental one is whether or not GPO-contracted prices are the lowest available. However, the fiercest controversy is around the "Contract Administration Fees (CAFs)" that GPOs charge to manufacturers. We examine these and other controversies using a Hotelling duopoly model.

Economic models can be extremely useful in the process of economic policy making. At the same time it should be emphasised that economic models should never be seen as a panacea for solving all kinds of economic problems. This paper discusses to what extent economic models could act as a useful tool in order to improve the quality in the process of economic policy making. For this purpose we will use the medium term annual model of the Bulgarian economy that recently has been developed at the Agency of Economic Analysis and Forecasting of the Bulgarian Ministry of Finance viz. the AEAF Model.

L'objet de ce papier n'est pas tant de présenter les principaux algorithmes utilisés en modélisation économique - nombre de manuels font des présentations de meilleure qualité et plus exhaustives - que d'en proposer une vision critique. Les modèles économiques, et plus particulièrement les modèles macroéconométriques, sont des représentations numériques qui, de ce fait, ont opéré des choix de simplification voire de réduction de la réalité. Revenir sur les algorithmes existants peut donc, nous l'espérons, constituer une étape vers la reformulation d'algorithmiques plus féconds pour la modélisation. Le problème de la modélisation consiste à se poser la question de savoir, compte tenu de l'état observé de l'économie et sous certaines hypothèses, quelle sera en mode projection, quelle serait (en mode simulation), l'état futur (vs l'état alternatif) de cette économie ? Depuis la phase de gestion de la banque de données qui requiert divers algorithmes de tri, jusqu'aux algorithmes d'analyse numérique impliqués dans les calculs matriciels d'estimation économétrique - pour être bref -, le fonctionnement de la modélisation macroéconométrique s'explique par des algorithmes . Il implique l'emploi d'une syntaxe, l'algorithmique, et d'un langage, les mathématiques. L'algorithme est une séquence d'instructions ordonnées et formalisées, permettant d'aboutir à la résolution du problème étudié. Peu d'ouvrages sont consacrés aux phases algorithmiques de la modélisation . Si les algorithmes visent tous à assister la décision (analyses rétrospective et prospective), ils sont loin de former une librairie homogène de programmes. Nous aborderons des algorithmes directement liés à un traitement numérique (estimation statistique, simulation optimisation). Mais nous consacrerons également quelques lignes à des algorithmes de nature apparemment "moins numériques", mais intervenant dans des phases déterminantes de la modélisation. Il s'agira d'une part des algorithmes permettant de structurer et/ou d'analyse des données ainsi que des algorithmes graphiques et ceux de communication. Enfin nous aborderons brièvement le problème de précision des calculs lié à l'arithmétique des ordinateurs. Délibérément, nous n'avons développé les aspects relatifs au Génie logiciel , de même que dans un souci de clarté, nous avons regroupé les programmes en annexe, lorsque la compréhension n'exigeait pas qu'ils accompagnent le texte. Notre présentation sera jalonnée de travaux algorithmiques et de références à nos notes de travail, réalisés dans le cadre de notre thèse de Doctorat.

This study tries to quantify the impact of transition in Eastern countries in an early stage on the cost-side and also on the benefit-side. The exposition plan includes: 1) Introduction; 2) Structural distortions; 3) Transition versus stability.

Background When allocating limited resources, public and private sector leaders in health policy consider both the health and economic value of new measures for cardiovascular disease (CVD) prevention. The ability to develop and prioritize policy measures is hindered by important gaps in health economics data. Methods and Results The Policy Research Implementation Group (PRIG) of the National Forum for Heart Disease and Stroke Prevention convened a symposium to develop priorities for research on the economics of CVD primary prevention and elimination of CVD disparities. Suggested top opportunities include expanded CVD surveillance, advances in evaluation and economic modeling of primary prevention, and use of behavioral economics to identify new prevention strategies. Enhanced policy, funding, and leadership support are vital to realizing this research agenda. Conclusions Targeted research on the health and economic value of CVD prevention, especially to eliminate CVD disparities, would bolster the justification for increased investment in cardiovascular health.

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