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Modelling tourism demand is essential when tourism policymakers plan tourism activities. The tourism industry is extremely susceptible to specific events’ effects, so good models must be found that reflect volatility. This study sought to review systematically the recent literature on this topic, specifically targeting models used to analyse tourism demand. The literature reveals some determinants of volatility in the tourism industry, such as income, gross domestic product and exchange rate, as well as crime, major events, big shocks, epidemics, weather conditions and the absence or existence of direct flights. Moreover, the review showed that modelling volatility is an emergent approach used in the analysis of tourism demand time series. This study’s results reveal pathways for the use of volatility models in tourism demand studies, which will allow managers and decision makers to adapt policies to deal with the volatility associated with tourism. info:eu-repo/semantics/publishedVersion

Customer churn has been stated as one of the main reasons of profitability losses in the telecommunications industry. As such, it seems critical to have an a priori knowledge about the risk of a given customer to churn at any moment, in order to take preventive measures to avoid the defection of potentially profitable customers. This study intends to develop a duration model of the residential customer churn in this industry in Portugal. We found empirical evidence that the variables that influence customer churn are the total number of overdue bills since ever, average monthly spending, average value of additional internet traffic, payment method, equipment renting, and the subscription of a flat plan. We also found that the probability of a customer to churn is neither constant over time nor across customers. info:eu-repo/semantics/publishedVersion

Bouça da Cova da Moura is the local place-name attributed to a stretch of a plateau overlooking the Leça valley. Here, Neolithic burial mounds share their landscape setting with scatters of archaeological materials that include Bell Beaker fragments, idols and metalwork. Since these are mostly surface findings, their contexts have not yet been accurately determined. Another significant feature is the presence of prehistoric rock carvings. The plateau may thus be considered a public space, conceptually and physically built over time. Its significance and meanings were certainly created and transmitted through practices of memory construction which are representative of cultural identity and social cohesion., Le site de Bouça da Cova da Moura se trouve sur un plateau faisant face au Rio Leça. On y a identifié des tertres funéraires du Néolithique, auxquels sont associés des zones de concentration d’artefacts, incluant céramiques campaniformes, idoles et mobilier métallique. S’agissant de mobilier de surface, le contexte de ces différentes concentrations n’a pas été déterminé avec attention. Un autre fait significatif est l’apparition de gravures rupestres préhistoriques. On peut considérer le plateau comme un espace publique, qui s’est bâti physiquement et conceptuellement au cours des temps. Son importance et sa signification ont certainement été créées et transmises à travers un certain nombre de pratiques de construction mémorielle, représentatives de l’identité culturelle et de la cohésion sociale.

This paper uses a threshold adjustment methodology to find out whether price transmission over the cod value chain between Norway and Portugal is asymmetric. The basic setting relies on price theory and the relationship between prices in the fish market. Empirical tests of price transmission use a cointegration framework similar to many other non-stationary time series analyses. However, it appears that testing for asymmetric price transmission has not been done so often in the fish market, despite the recent availability of non-linear time series techniques designed to this end. TAR and M-TAR adjustment models can be used in this context. Our results show that while the three price series used in the cod value chain between Norway and Portugal are cointegrated, there is no evidence of asymmetric price adjustment in this market.

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The extent to which demand and supply shocks are transmitted in the value chain is an important topic. As many value chains cross international borders exchange rate pass through is an important element in this context. In this paper a multivariate system that allow us to test different hypothesis with respect to the value chain is specified. This include tests of whether there is a link between the different stages in the value chain, whether the exchange rate pass through is complete and whether price signals are fully transmitted. Different exogeneity assumptions are testable hypothesis, and one can avoid the simultaneity problem associated with the common single equation specifications. Moreover, one can also test whether the exchange rate is determined outside the system, as well as testing for price leadership. An application is provided for the value chain for cod between Norway and Portugal.

In this report we investigate the value chains for two of the most important species in the sea food trade in Europe, cod and salmon, using only price data. For cod we investigate value chains from Norway to Portugal and within the UK, while we investigate the value chains from Norway and the UK into France and from Norway to Finland for salmon. For cod, both value chains seem highly competitive, although there is also increased concentration. As expected, given that several market integration studies have shown that Norwegian and Scottish salmon are close substitutes, the value chains between the two producers are also related. The value chains appear to be competitive at the first stages upstream. When one goes further up in the chain the picture is less clear. At some stages the chain still seems competitive, though this is most commonly associated with traditional chains where there are still small firms, and for the least processed products. The evidence against competition is strongest when the retailers are supermarkets. However, this does not seem to be a sign of utilization of market power, as supermarkets tend to have lower prices. Hence, for both species higher concentration mainly seems to be a necessary adjustment to exploit scale economies in new distribution technologies.

The main objectives of this research are to identify, through a systematic literature review, the potential benefits of the use of volatility models in tourism, to study the volatility of tourism demand in cities and to compare models of volatility between different destinations and source markets. The three cities analysed in Portugal were Coimbra, Lisbon and Oporto and the source markets that were studied were the domestic market, the total overnight stays, Brazil, France, Germany, Italy, Spain, the United Kingdom and other non-specified countries. The systematic review of the literature was carried out in order to identify, in a temporal perspective, the use of each methodology, variables used, data frequencies, temporal window, type of territories and geographic object of each study. The semantic analysis of the state of the art was also a methodology used. After a preliminary analysis of the time series, models that literature indicates as more suitable to estimate the volatility were used, namely, models of autoregressive conditional heteroscedasticity: ARCH, GARCH, EGARCH and TGARCH models. The most suitable models for each source market, in each city, were identified, as well as the existence of asymmetries face to positive and negative shocks, their magnitude and their persistence. Different models of volatility were identified in each city for each source market, as well as, different types of persistence of volatility, in each market and city, and different magnitude in face of good news and bad news, which strengthens the need to adjust the modelling of tourism demand for each market and, within a country, at a more detailed territorial scale. The use of volatility models is quite recent in tourism demand modelling and had not yet been applied in cities in Portugal, for which, despite the growing importance in terms of tourism, there are no studies of modelling focusing on the tourism demand. Modelling tourism demand is essential when tourism policymakers plan tourism activities. The tourism industry may be extremely sensitive to specific events’ effects, so good models must be found that reflect volatility that varies within each city and for each source market and policies must be adapted to each of the source/destination pairs.

Along with the global trend of informatization, Internet has become a new mainstream media form following such forms as print media, television and broadcast media, via which people can access information services. As a country with the largest number of netizens around the world, China enjoys improving social information services based on the Internet. With such a large quantity of network users, it is inevitable for China's hospitals at various levels to provide patients and the public with information services by setting up their own official websites. This research investigates the factors affecting the information service quality of Wenzhou People's Hospital (WZPH) and by means of Delphi method, statistical analysis and other research methods, formulates the Evaluation Indicator System for the Information Service Quality of WZPH's Information Platform. The research applies this system to the empirical research on the information service quality of the hospital's website and then makes a comparative analysis between the research results and traffic data of the websites of other hospitals over the same period. Next, the research identifies the factors affecting the information service quality of WZPH's website and finds out how the hospital may increase its website users and traffic through improving its service quality. This research starts with the determination of the objectives, significance, research problems, framework, contents and methods of the research. In the following literature review, the research sorts out papers on hospital websites and theories on service quality, users' information needs and customer satisfaction in a systematic way. Based on the literature review as well as expert consultations and theoretical review, the research determines the approach to examining the information service quality of WZPH's information platform and works out the initial set of evaluation dimensions and indicators of the information service function and quality of the hospital's website. Then, via two rounds of expert consultations, the research figures out the weights of these indicators and further assigns values to each of them. On this basis, the research establishes a research framework and a comprehensive evaluation model for the information service quality of WZPH's information platform. In the end, the research conducts two surveys respectively on the information service quality of WZPH's information platform before and after its overall revision by using Hospital Website Information Service Evaluation Form and Virtual User Questionnaire, and makes a correlation analysis based on the survey results and the flow data of other hospitals' websites over the same period. The analysis draws a conclusion that the website of WZPH, as the information platform of the hospital, is the only carrier to deliver information service, thus playing a vital role in WZPH's overall service quality. In other words, the website of WZPH affects the hospital's overall service quality to a large extent. The comprehensive service function of WZPH's website are important to the quality improvement of the hospital's information service and directly affect the information service quality, the number of users as well as utilization rate of the website.

In responding to subprime crisis with its peak with the bankruptcy of investment bank Lehman brothers in September of 2008, marking the end of the “great moderation”, several governments and central banks of developed and emerging economies change the respective fiscal and monetary policies, in order to stimulate the economy, some more than others, creating spillovers and transmit them by different channels through the stocks market worldwide. Furthermore, due to recent debate of the implementation of similar monetary stimulus program in China, like to the ones implemented in US and in currently in development in Euro Area, is relevant access the f policies consequences in China. The present work particularly focusses on the consequences of monetary and fiscal policies implemented in the United States, United Kingdom, Euro Area, Japan in China. The results show that the spillovers of the international fiscal and monetary policy are overall nonexistent or weak at best. However, there are significant spillovers of United States and Japan with China, the monetary policy of US has positive impact and the fiscal has negative impact on Shanghai stock returns, the same is true of the Japanese monetary policy. Na resposta a crise do subprime com o seu auge com a falência do banco Lehman Brothers em setembro de 2008, marcando o fim da “grande moderação”, vários governos e bancos centrais de países desenvolvidos e em desenvolvimento mudaram as suas respetivas fiscais e monetárias, em ordem a estimular a economia, alguns com maior ímpeto que outas, criando spillovers e transmitindo os mesmos por diferentes canais para os mercados acionistas a nível mundial. Para alem do mais, devido ao recente debate de implementação de um programa de estímulos monetários semelhante na China aos que foram implementados nos EUA e atualmente em desenvolvimento na Área do Euro, é pertinente avaliar se os impactos das consequências destas politicas nos países desenvolvidos nos países emergente e viceversa. O presente trabalho foca-se nas consequências das politicas fiscais implementas nos Estados Unidos, Reino Unido, Área do Euro, Japão e China. Os resultados mostram que os spillovers das politicas monetária e fiscais seguidas por estes países são nulos ou muito residuais. Contudo, existe spillovers significativos dos Estados Unidos e do Japão com a China, a politica monetária dos Estados Unidos tem um impacto positivo e a politica fiscal tem um impacto negativo nos retornos do mercado acionista de Shanghai, o mesmo é verdade para a politica monetária japonesa.

JEL Classification System: G15; C13 In this study we examine the long memory behaviour of stock market volatility of the PIIGS major indices: PSI 20, FTSE MIB, ISEQ, FTSE/ATHEX and IBEX 35. In order to conduct our analyses we apply two FIGARCH-type models, one derived by Baillie, Bollerslev and Mikkelsen (1996) and another one developed by Chung’s (1999). In addition the Local Whittle estimator is also computed. A data set comprising the daily closing prices of the PIIGS’ major stock market indices spanning from 1st January 1998 to 8th March 2013 is used. The results suggest that, irrespective of the FIGARCH model adopted, there is evidence of long memory in stock market volatility. However, the Local Whittle Estimator reveals that the data generating process is a combination of long memory and jumps/structural breaks. Therefore, this feature of the data has to be taken into account when constructing models for volatility prediction. Neste estudo examinamos o comportamento de longa memória na volatilidade dos principais índices de mercado dos PIIGS: PSI20, FTSE MIB, ISEQ, FTSE/ATHEX e IBEX 35. Para realizar a nossa análise aplicámos dois modelos do tipo FIGARCH, um derivado por Baillie, Bollerslev e Mikkelsen (1996) e outro desenvolvido por Chung (1999). Adicionalmente, o Local Whittle Estimator foi também estimado. Um conjunto de dados dos principais índices de mercado de acções dos PIIGS que inclui os preços de fecho diários desde 1 de Janeiro de 1998 até 8 de Março de 2013 foi utilizado. Os resultados sugerem que, independentemente do modelo FIGARCH adoptado existem evidências de longa memória na volatilidade do mercado. No entanto, o Local Whittle Estimator revela que o processo de criação de dados é uma combinação de longa memória e saltos/quebras estruturais. Assim sendo, esta característica dos dados tem de ser tida em conta na construção de modelos de previsão de volatilidade.

Considering that profits from customer relationships are the lifeblood of firms (Grant and Schlesinger, 1995), an improvement on the customer management is essential to ensure the competitivity and success of firms. For the last decade, Portuguese customers of fixed telecommunications industry have easily switched the service provider, which has been very damaging for the business performance and, therefore, for the economy. The main objective of this study is to analyse the partial churn of residential customers in the fixed-telecommunications industry (fixed-telephone and ADSL), by using survival models. Additionally, we intend to test the assumption of constant customer retention rate over time and across customers. Lastly, the effect of satisfaction on partial customer churn is analysed. The models are developed by using large-scale data from an internal database of a Portuguese fixed telecommunications company. The models are estimated with a large number of covariates, which includes customer’s basic information, demographics, churn flag, customer historical information about usage, billing, subscription, credit, and other. Our results show that the variables that influence the partial customer churn are the service usage, mean overall revenues, current debts, the number of overdue bills, payment method, equipment renting, the existence of flat plans and the province of the customer. Portability also affects the probability of churn in fixed-telephone contracts. The results also suggest that the customer retention rate is neither constant over time nor across customers, for both types of contracts. Lastly, it seems that satisfaction does not influence the cancellation of both types of contracts. Considerando que os lucros gerados pelos clientes são vitais para as empresas (Grant e Schlesinger, 1995), uma melhoria na gestão do cliente é fundamental para assegurar a competitividade e o sucesso das empresas. Na última década, os clientes portugueses das empresas de telecomunicações fixas têm mudado de operador com demasiada facilidade, o que tem prejudicado o desempenho das empresas e, consequentemente, a economia. O principal objectivo deste estudo é analisar o cancelamento de contratos de telefone fixo e ADSL por clientes residenciais, através do uso de modelos de sobrevivência. Para além disso, pretende-se testar o pressuposto de que a taxa de retenção de clientes é constante ao longo do tempo e entre clientes. Por último, pretende-se analisar o efeito da satisfação do cliente no cancelamento destes tipos de contratos. Os modelos são construídos com base numa base de dados de larga escala fornecida por uma empresa portuguesa deste sector. Os modelos são estimados com base num vasto número de variáveis, incluindo informação básica sobre o cliente, dados demográficos, indicação sobre o cancelamento do contrato, dados históricos sobre o uso dos serviços, facturação, contracto, crédito, etc.. Os resultados mostram que as variáveis que influenciam o cancelamento de ambos os tipos de contratos são o uso do serviço, a facturação média, o valor em dívida, o número de facturas em dívida, o método de pagamento, o método de pagamento do equipamento, a existência de tarifas planas e o distrito do cliente. A portabilidade de número parece influenciar o cancelamento de contratos de telefone fixo. Os resultados também mostram que a taxa de retenção de clientes não é constante ao longo do tempo nem entre clientes em ambos os tipos de contratos. Por último, parece que a satisfação não influencia o cancelamento de ambos os tipos de contratos.

The aim of this work is to study the dynamic relationship between prices of wholesale electricity market in Spain and prices of the main fuel references to generate electricity (coal, crude oil, gasoil and natural gas). The dynamic relationship between the various interconnected electrical systems (Spain and Portugal, Spain and France), using as reference prices for wholesale electricity markets formed in each electrical system, is also relevant for analysis purposes due to impacts on prices of wholesale electricity market in Spain. The results suggest: cointegration between prices of wholesale electricity market in Spain and the variables under analysis (fuel and wholesale electricity market prices); a long-term relationship between prices of wholesale electricity market in Spain, coal prices, crude oil prices, gasoil prices, natural gas prices of the Dutch TTF market and the prices of wholesale electricity market in Portugal; a short-run relationship between prices of wholesale electricity market in Spain and natural gas prices of the English NBP market and Belgian Zeebrugge market; the presence of strong exogeneity in the relationship between prices of wholesale electricity market in Spain and prices of wholesale electricity market in France; proportionality between crude oil prices, natural gas prices of the Dutch TTF market and prices of wholesale electricity market in Spain; and the evidence of asymmetry in the electricity prices from the wholesale market in Portugal with “steep” movements in relation to prices of wholesale electricity market in Spain. A number of implications will be addressed. Pretende-se com este trabalho estudar a relação dinâmica entre os preços de electricidade do mercado grossista em Espanha e os preços das principais referências de combustível para a geração de electricidade (carvão, petróleo, gasóleo e o gás natural). A relação dinâmica entre os diferentes sistemas eléctricos interligados (Espanha e Portugal, Espanha e França), utilizando como referência os preços de electricidade dos mercados grossistas formados em cada sistema eléctrico, também é relevante para efeitos de análise, pois impacta na evolução dos preços de electricidade do mercado grossista em Espanha. Os resultados sugerem: cointegração entre os preços de electricidade do mercado grossista em Espanha e das variáveis em análise (combustíveis e preços de electricidade grossistas); relação de longo prazo entre os preços de electricidade do mercado grossista em Espanha, os preços do carvão, os preços do petróleo, os preços do gasóleo, os preços do gás natural do mercado holandês TTF e os preços de electricidade do mercado grossista em Portugal; relação de curto prazo entre os preços de electricidade do mercado grossista em Espanha e os preços do gás natural do mercado inglês NBP e do mercado belga Zeebrugge; foi encontrada exogeneidade forte na relação entre os preços de electricidade do mercado grossista em Espanha e os preços de electricidade do mercado grossista em França; proporcionalidade entre os preços do petróleo, os preços do gás natural do mercado holandês TTF e os preços de electricidade do mercado grossista em Espanha; e a evidência de assimetria dos preços de electricidade do mercado grossista em Portugal com movimentos “abruptos” na sua relação com os preços de electricidade do mercado grossista em Espanha. Uma série de implicações serão abordadas.