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The determinants of mortgage default have been an area of rising interest since the 2008 recession. There are two distinguishing features of mortgage default analysis. First, predictor variables are often only recorded at origination. However, many important variables such as credit scores vary over time. Second, there are omitted variables (such as borrower's income and job security). If omitted variables are correlated with included regressors or if only origination values are used in a dynamic model, then biases may be present in econometric models for default risk. Our focus is to develop a ridge regression model to impute the dynamics of time-varying predictors and to capture unobserved borrower heterogeneity. The model is evaluated using cross-validation, and the relevant parameters are tuned to maximize out-of-sample predictive performance. After allowing for imputed dynamics and borrower heterogeneity, we find that the loan-to-value ratio becomes a larger signal of default risk and that credit scores as well as full documentation become smaller signals of default risk. These changes primarily are driven by imputing static variables, rather than dynamics, and may pertain to either omitted liquidity factors or strategic factors. [ABSTRACT FROM AUTHOR]

The destiny of the electric vehicle (EV) marketplace will depend upon the behaviour of potential buyers and on how emerging markets allow EVs to be perceived as a mobility solution to the externalities generated by internal combustion (IC) vehicles. To this end it is important to ascertain the role played by psychological factors, along with instrumental attributes, especially among younger adults (future purchasers) in not yet mature markets. Our paper analyses and models the propensity to purchase an EV with respect to an equivalent IC vehicle. It contributes to the existing literature investigating younger adults' behaviour in an emerging market, focusing on the role of attitudes and perceptions. A stated preferences survey, built on real commercial scenarios (Renault ZOE vs Renault Clio), was designed and disseminated at the University of Cordoba (Argentina). Respondent behaviour was modelled within the random utility paradigm. First, heterogeneity among users was investigated through mixed multinomial logit formulation; The role of psycho-attitudinal factors was then explored through the specification of hybrid choice models with latent variables. Estimation results indicate the significant role of attitudes and perceptions in emerging markets. [ABSTRACT FROM AUTHOR]

The strategy of geographically diversifying a portfolio of commercial real estate assets is an intuitive approach for risk management. However, due to high concentrations of these assets in major metropolitan areas, investors may face additional constraints in the portfolio optimization process. The rank-size rule, a log-linear relationship between city rank and size, provides one of the greatest empirical regularities in regional science. As such, it serves as a possible theoretical guide to the weights given to properties by location in a commercial real estate portfolio. This paper sets forth some ideas relating to the concentration side of portfolio variance and the limiting effect that large concentrations may have on the ability to diversify risk. Two variants of the rank-size relationship – the Zipf distribution and the parabolic fractal distribution – are fitted to a variety of datasets to provide a sense of the degree of concentration in the commercial real estate industry. These empirical findings suggest the presence of limitations to geographical diversification that have varying degrees of severity across different property types or sectors of the commercial real estate market. [ABSTRACT FROM AUTHOR]

For understanding the electrical and optical properties of electrodeposited Cl-doped Cu2O thin films, we have studied layers with increasing thickness and Cl concentrations of 0.8 and 1.2 at. %. The deposits were characterized by measuring the charge transport, the optical reflectance, and the photoluminescence. No significant decrease of electrical resistivity was observed in doped samples compared to undoped ones. A decrease of about five orders of magnitude was measured and ascribed to the presence of pinholes, as confirmed by scanning electron microscopy analyses. From optical measurements, we concluded that the Cl atoms are incorporated into substitutional sites of Cu2O lattices in agreement with photoluminescence results showing a strong reduction in the peak intensity of VO+2 defects in comparison to undoped layers. Computational calculation using density functional theory has pointed out high formation energy for single Cl related defects, but low formation energy for Cl-defect complexes, such as ClO + VCu, that strongly compensate the carriers generated by the Cl doping. [ABSTRACT FROM AUTHOR]

Automated valuation models (AVMs) are widely used by financial institutions to estimate the property value for a residential mortgage. The distribution of pricing errors obtained from AVMs generally show fat tails (Pender 2016; Demiroglu and James Management Science, 64(4), 1747–1760 2018). The extreme events on the tails are usually known as "black swans" (Taleb 2010) in finance and their existence complicates financial risk management, assessment, and regulation. We show via theory, Monte Carlo experiments, and an empirical example that a direct relation exists between non-normality of the pricing errors and goodness-of-fit of the house pricing models. Specifically, we provide an empirical example using US housing prices where we demonstrate an almost perfect linear relation between the estimated degrees-of-freedom for a Student's t distribution and the goodness-of-fit of sophisticated evaluation models with spatial and spatialtemporal dependence. [ABSTRACT FROM AUTHOR]

Practical implications: The present report documents two successful single appointment regenerative endodontic therapy using desiccant agent Hybenx cleanser in necrotic teeth with incomplete root development and apical lesion. After discussing the possible treatment options, patient's parents approved the regenerative endodontics therapy and provided informed written consent. Keywords: Mineral Trioxide Aggregate; Necrotic immature teeth; Regenerative endodontics; Root canal irrigants EN Mineral Trioxide Aggregate Necrotic immature teeth Regenerative endodontics Root canal irrigants 1870 1875 6 04/29/21 20210401 NES 210401 A case of regenerative endodontics: (a) before treatment; (b) post-treatment Xray; (c) follow-up at 6 months; (d) follow-up at 12 months. [Extracted from the article]

Social distancing, a non-pharmaceutical tactic aimed at reducing the spread of COVID-19, can arise because individuals voluntarily distance from others to avoid contracting the disease. Alternatively, it can arise because of jurisdictional restrictions imposed by local authorities. We run reduced form models of social distancing as a function of county-level exogenous demographic variables and jurisdictional fixed effects for 49 states to assess the relative contributions of demographic and jurisdictional effects in explaining social distancing behavior. To allow for possible spatial aspects of a contagious disease, we also model the spillovers associated with demographic variables in surrounding counties as well as allow for disturbances that depend upon those in surrounding counties. We run our models weekly and examine the evolution of the estimated coefficients over time since the onset of the COVID-19 pandemic in the United States. These estimated coefficients express the revealed preferences of individuals who were able to and chose to stay at home to avoid the disease. Stay-at-home behavior measured using cell phone tracking data exhibits considerable cross-sectional variation, increasing over nine-fold from the end of January 2020 to the end of March 2020, and then decreasing by about 50% through mid-June 2020. Our estimation results show that demographic exogenous variables explain substantially more of this variation than predictions from jurisdictional fixed effects. Moreover, the explanations from demographic exogenous variables and jurisdictional fixed effects show an evolving correlation over the sample period, initially partially offsetting, and eventually reinforcing each other. Furthermore, the predicted social distance from demographic exogenous variables shows substantial spatial autoregressive dependence, indicating clustering in social distancing behavior. The increased variance of stay-at-home behavior coupled with the high level of spatial dependence can result in relatively intense hotspots and coldspots of social distance, which has implications for disease spread and mitigation. [ABSTRACT FROM AUTHOR]

Machine learning algorithms such as neural nets, support vector machines, and tree-based techniques (classification and regression trees) have shown great success in dealing with a number of complex problems (Hastie et al. 2009). However, real estate data exhibit both temporal dependence and high levels of spatial dependence (Pace et al., International Journal of Forecasting16(2), 229–246, 2000; LeSage and Pace 2009) that may make it harder to use with off-the-shelf machine learning procedures. We examine tree-based techniques (CART, boosting, and bagging) and compare these to spatiotemporal methods. We find that bagging works well and can give lower ex-sample residuals than global spatiotemporal methods, but do not perform better than local spatiotemporal methods. [ABSTRACT FROM AUTHOR]

Although some have proposed eliminating the National Flood Insurance Program (NFIP) to reduce government expenditures, other alternatives exist that could reduce the cost of the program and increase its viability, such as increasing deductibles, which may increase participation and revenue. The​ recently released FIMA NFIP Redacted Policies Data Set provides unprecedented opportunities to examine homeowner deductible choices for flood insurance policies using policy-level data. The menu of deductibles currently ranges from $1,000 to $10,000 in Special Flood Hazard Areas (SFHAs), but until April 1, 2015, the maximum deductible was $5,000. Using a matched sample of 252,280 SFHA policies that were active for the 2013–2019 time period, we provide insight regarding characteristics of homeowners who chose the maximum deductible as well as those who switched from the $5,000 to the new $10,000 deductible. Consistent with nudge theory and stickiness, we show that the majority of the homeowners accept the default deductible option. Individuals in high-income and high-premium areas were more likely to select the maximum dedu​ctible. Level of education and past flood events do not impact whether people decide to select the maximum deductible option. [ABSTRACT FROM AUTHOR]

Maintenance and improvements affect house values and thus the observed pecuniary return. Whether due to lack of liquidity or the presence of strategic incentives, some borrowers have a higher probability of default and this could lead to lower maintenance and investment in the property. We test this hypothesis using a sample of properties on which we have repeat sales and mortgage information. We find that the predicted probability of default at the time of the original purchase significantly reduces subsequent observed pecuniary return. For instance, an increase in the probability of default from 22% to 32% leads to an 0.5% reduction in appreciation per year. Because the future house price varies with borrower risk, we examine many simulated scenarios to analyze the implications of the findings. From these scenarios, we observe that the highest risk borrowers can experience approximately 3% less appreciation per year than the lowest risk borrowers. [ABSTRACT FROM AUTHOR]

Search theory shows that real property prices and marketing durations are simultaneously determined and positively related. Yet, empirical studies find positive, negative, and insignificant parameter estimates on the time-on-the-market (TOM) variable in price models. Using a dataset well suited to the research question, this article investigates reasons for the divergence between the theoretical and empirical results. Our test equations examine the quality of instrumental variables, severe overpricing, atypicality, structure quality, loss aversion, market tightness as well as measures unique to our data such as sellers' income levels, reasons for sale, and urgency. We find that weak instrumental variables account for the varied empirical relations between transaction prices and TOM. [ABSTRACT FROM AUTHOR]

The knowledge of how oxygen atoms are distributed at a magnetic-metal/oxide, or magnetic-metal/non-magnetic-metal interface, can be a useful tool to optimize device production. Multilayered Ni81Fe19/Ta samples consisting of 15 bilayers of 2.5 nm each, grown onto glass substrates by magnetron sputtering from Ni81Fe19 and Ta targets, have been investigated. X-ray absorption near edge structure, extended X-ray absorption fine structure, small angle X-ray diffraction, and simulations were used to characterize the samples. Oxygen atoms incorporated onto Ni81Fe19 films during O2 exposition are mainly bonded to Fe atoms. This partial oxidation of the Ni81Fe19 surface works as a barrier to arriving Ta atoms, preventing intermixing at the Ni81Fe19/Ta interface. The reduction of the Ni81Fe19 surface by the formation of TaOx is observed. [ABSTRACT FROM AUTHOR]

We discuss Monte Carlo methodology that can be used to explore alternative approaches to estimating spatial regression models. Our focus is on models that include spatial lags of the dependent variable, e.g., the SAR specification. A major point is that practitioners rely on scalar summary measures of direct and indirect effects estimates to interpret the impact of changes in explanatory variables on the dependent variable of interest. We argue that these should be the focus of Monte Carlo experiments. Since effects estimates reflect a nonlinear function of both β and ρ, past studies’ focus exclusively on β and ρ parameter estimates may not provide useful information regarding statistical properties of effects estimates produced by alternative estimators. Since effects estimates have recently become the focus of inference regarding the significance of (scalar summary) direct and indirect impacts arising from changes in the explanatory variables, empirical measures of dispersion produced by simulating draws from the (estimated) variance-covariance matrix of the parameters β and ρ should be part of the Monte Carlo study. An implication is that differences in the quality of estimated variance-covariance matrices arising from alternative estimators also plays a role in determining the accuracy of inference. An applied illustration is used to demonstrate how these issues can impact conclusions regarding the performance of alternative estimators. [ABSTRACT FROM AUTHOR]

Aims To investigate whether polycystic ovary syndrome further increases postpartum diabetes risk in women with gestational diabetes mellitus and to explore relationships between polycystic ovary syndrome and incident diabetes in women who do not develop gestational diabetes. Methods This retrospective cohort study (Quebec Physician Services Claims; Hospitalization Discharge Databases; Birth and Death registries) included 34 686 women with gestational diabetes during pregnancy (live birth), matched 1:1 to women without gestational diabetes by age group, year of delivery and health region. Diagnostic codes were used to define polycystic ovary syndrome and incident diabetes. Cox regression models were used to examine associations between polycystic ovary syndrome and incident diabetes. Results Polycystic ovary syndrome was present in 1.5% of women with gestational diabetes and 1.2% of women without gestational diabetes. There were more younger mothers and mothers who were not of white European ancestry among those with polycystic ovary syndrome. Those with polycystic ovary syndrome more often had a comorbidity and a lower proportion had a previous pregnancy. Polycystic ovary syndrome was associated with incident diabetes (hazard ratio 1.52; 95% CI 1.27, 1.82) among women with gestational diabetes. No conclusive associations between polycystic ovary syndrome and diabetes were identified (hazard ratio 0.94; 95% CI 0.39, 2.27) in women without gestational diabetes. Conclusion In women with gestational diabetes, polycystic ovary syndrome confers additional risk for incident diabetes postpartum. In women without gestational diabetes, an association between PCOS and incident diabetes was not observed. Given the already elevated risk of diabetes in women with a history of gestational diabetes, a history of both polycystic ovary syndrome and gestational diabetes signal a critical need for diabetes surveillance and prevention. [ABSTRACT FROM AUTHOR]

A seller sets the list price based upon their ex- ante perception of the trade-off between marketing duration versus transaction price, which depends on the liquidity of the property and the depth of the market. As such, list prices reflect property, market, and seller characteristics. In addition, Genesove and Mayer (2001) and Bokhari and Geltner (2011) use prospect theory to motivate how expected nominal losses and gains from sale can also influence list prices. We consider these multiple factors affecting list prices through a rich dataset from the National Association of Realtors, which contains variables on seller motivations, structure liquidity, and other difficult to observe variables such as seller age, race, and income. [ABSTRACT FROM AUTHOR]

Hedonic pricing, estimating the value of housing characteristics through the use of transactions data, is one of the most common tasks performed by real estate researchers. However, transaction frequency varies over time, locations, and other factors. In contrast, two-thirds of homeowners have mortgages that they pay each month. This manuscript explores the use of mortgage payment data as an alternative or supplemental means to derive the value of housing characteristics. Insofar as price affects default and housing characteristic values determine price, housing characteristic values affect default. The implicit housing characteristic values come from parameter values that fit observed patterns of payments and defaults. We find a strong correlation (0.74−0.92) between the transaction-based and the implicit approaches. In addition, the Monte Carlo simulation indicates that the mortgage based pricing model has potential to help reveal housing market information especially during low sales activity and/or high default rate situations. [ABSTRACT FROM AUTHOR]

During a 5-year period from 2010 to 2014, n = 919 samples of feed and raw materials were analyzed for aflatoxin B (AFB) contamination using accredited ELISA screening methods. Only 0.76 % of these samples were non-compliant with maximum levels set by the European Union Regulation 32/2002. Non-compliant samples were mainly from the province of Bari ( n = 3 samples, mean AFB value 7.03 μg/kg), although the highest AFB levels were found in two samples from the provinces of Foggia and Brindisi, at 32.6 ± 3.6 μg/kg and 31.0 ± 4.0 μg/kg, respectively. Mean AFB levels in samples contaminated but compliant with the limits ranged from 1.4 to 2.2 μg/kg. Considering the great importance of climate conditions in mycotoxins production, during crops production and during the critical phases of materials storage and/or transport, to better understand the variability in contamination levels, the analytical results were reviewed in term of temperature and relative environmental humidity in the sampling areas. Correlations between aflatoxin B levels in feed and these climate factors might explain seasonal and annual variations in contamination levels. The data from the present study provide useful suggestions for the organization of targeted monitoring plans and the protection of consumers, as well as for improvement in the quality standards of zootechnological activities and feed industry. [ABSTRACT FROM AUTHOR]

The Problem. The Academy of Human Resource Development (AHRD) evolved out of a perception that a practitioner-focused professional association (American Society for Training and Development [ASTD]) was not accommodating the interests of many members of the academic community, especially during annual meetings. Although a Professor’s Network existed, in the context of a meeting of working professionals, the network was too restricted in the kinds of scholarly presentations that could be made. The Solution. Ultimately, most of the academicians who were members of ASTD coalesced into a determined group dedicated to fashioning an independent society and creating a successful scholarly association. The Stakeholders. Members of AHRD—whether practitioners or scholars—will find it instructive to learn the behind the scenes story of the evolution of a professional association. For all who might imagine embarking on a similar process of invention, the connections between a personal life trajectory of the founder and the needs of a profession provide a study in perseverance and vision. [ABSTRACT FROM AUTHOR]

Existing price indices are based on real estate sales. This approach encounters problems when (1) sales are infrequent or (2) when these differ systematically from the overall market (selection bias). Relative to the number of properties sold on the market, a much greater number of properties have borrowers who need to make monthly mortgage payment decisions. Therefore, each month borrowers cast a vote of confidence or no confidence in their price relative to the loan balance. Based on this behavior, we invert the relation between mortgage performance and prices to derive a latent price index. Using a large sample of individual mortgages across the 10 cities investigated, the latent index in each city has a high correlation with the respective Case-Shiller index. In addition, the latent index is partially explained by the housing expectations (derived from futures on the respective Case-Shiller index) which indicates that it is not a purely reactive measure. Overall the results show that the latent index has potential to boost information resources for tracking the important real estate sector. [ABSTRACT FROM AUTHOR]

This paper conducts loan-level analysis to investigate the influence of expected foreclosure delay on a borrower's default propensity. We include the actual foreclosure times in the analysis to capture the dynamic nature of foreclosure duration. Consistent with theoretical predictions, we find a statistically and economically significant impact of foreclosure delay on borrower default behavior. In the current market condition where many borrowers have negative equity, the increase in delay may make default an optimal choice for more borrowers. The negative effect of increased foreclosure delay may need to be considered when devising policies to aid troubled borrowers. [ABSTRACT FROM AUTHOR]

The growth of aluminum nitride thin films onto various substrates (glass, flexible polyimide, or silicon) and onto different buffer layers (Au, Nb, Cu, Ag, Co, Fe, NiFe, or IrMn) is reported. Samples grown on IrMn, Co, NiFe, Nb, or Au show smooth surfaces. This same smooth quality is observed in samples grown at a lower 200 °C temperature directly on glass, Si, or flexible polyimide. In applications where thin and smooth piezoelectric films are necessary, c-axis-oriented AlN can be grown onto a wide range of different surfaces: conducting, insulating, ferromagnetic, antiferromagnetic, or flexible. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper proposes and compares different approaches within the general fixed-point framework that allows to deal with multi-user (stochastic) equilibrium assignment with variable demand (VD). The aim was threefold: (i) compare the efficiency and the effectiveness of the internal and the external approaches to stochastic equilibrium assignment with VD; (ii) investigate the efficiency and the effectiveness of different algorithms based on the method of successive averages and its extensions; (iii) investigate the effects of different averaging schemes, different convergence criteria and different path choice models, such as Multinomial Logit model, C-Logit model and Multinomial Probit model. Analyses were carried out with respect to a real network and considering different indicators of both efficiency and effectiveness. [ABSTRACT FROM AUTHOR]

House price regression residuals often display spatial dependence but historically mortgage models, which employ house prices, assume independence and use only the own borrower/loan characteristics. This manuscript uses a spatial probit model to investigate spatial dependence among the disturbances and the effect of borrower/loan characteristics from nearby properties on own default propensity. We find that allowing spatial dependence in the disturbances greatly improve the predictive accuracy of a probit default model, and that spillovers from risky neighbor characteristics have statistically significant and material effects on own payment default propensity. In addition, measurement of spatial effects can improve policy analysis. [ABSTRACT FROM AUTHOR]

Context. Pre-hospital administration of hydroxocobalamin (B12a) is used for empiric treatment of cyanide poisoning because cyanide poisoning is difficult to identify and requires immediate treatment. B12a interferes with the accuracy of several blood laboratory tests. This study aimed to explore how B12a affects carboxyhemoglobin (COHb) measurements in human blood at both physiologic and pathologic COHb levels. Methods. Several clinically relevant concentrations of B12a were added to human blood samples containing physiologic (∼ 3%) and pathologic (30% and 50%) COHb levels. We then measured the COHb levels of the samples using two different co-oximeters, the Radiometer ABL 700 and the Rapidpoint 500, and compared to their actual baseline COHb levels. Results. B12a had minimal effects on the COHb measured at both physiologic and pathologic levels when measured on the Radiometer. In contrast, the Rapidpoint B12a caused a dose-dependent decrease in the COHb measured, especially of pathologic COHb levels (∼ 30 and 50%). Conclusion. The magnitude of B12a interference on measured COHb is dependent upon the specific co-oximeter used, the actual COHb level and the serum B12a concentration. These errors may potentially influence clinical decision making and thus affect patient outcomes. Our findings emphasize the importance of measuring COHb levels on blood samples collected prior to B12a administration. [ABSTRACT FROM AUTHOR]

We investigate the angular dependence of asymmetric magnetoimpedance of NiFe/IrMn multilayers and explore the possibility of tuning the linear region of the magnetoimpedance curves by modifying the angle between the applied external magnetic field and exchange bias field, and probe current frequency. We quantify the sensitivity by calculating the ratio |ΔZ|=|ΔH| at low magnetic fields as a function of the frequency for samples cut with different orientations and show that considerable values in the linear region around zero field can be reached. The results extend the possibilities for application of exchange biased magnetoimpedance multilayers as probe element for the development and improvement of auto-biased linear magnetic field sensors. [ABSTRACT FROM AUTHOR]

This study compares student ratings of finance professors to faculty ratings in other academic disciplines and identifies some of the factors responsible for those differences using data from RateMyProfessors.com. Empirical results show that students in finance classes perceive their classes as significantly more difficult than students in many other disciplines do and that these different perceptions are associated with significantly lower teacher evaluations for finance faculty. These results indicate that lower teaching ratings may be more a function of discipline based student perceptions of class difficulty rather than a function of professor teaching ability. These findings are important for any finance faculty member who must provide teaching evaluations as part of annual reviews and tenure and promotion applications. The results should also serve as a warning to administrators and committees that comparison of teaching ratings across disciplines is often an invalid basis for assessing relative teaching proficiency and effectiveness. [ABSTRACT FROM AUTHOR]

The alpha-carotene, beta-carotene and total provitamin A carotenoids and the effect of traditional processing practices on the retention of these provitamins were studied using amaranth, cowpea, peanut, pumpkin and sweet potato leaves. Results of this study indicated that the content of total carotenoids, beta-carotene and alpha-carotene were in the range of 26.79-44.74 mg, 4.16-19.12 mg, and 0.99-10.26 mg per 100 g of dry vegetables, respectively. The vitamin A activities were 4.042, 3.124, 0.829, 2.025 and 1.581 mg RE per 100 g of dry amaranth, cowpea, peanut, pumpkin and sweet potato leaves, respectively. The traditional processing practices of sun drying and storage in ventilated containers resulted in a significant (p < 0.05) decrease in the concentration of total carotenoids, beta-carotene and alpha-carotene for all the vegetables. Conventional blanching and cooking resulted in a significant (p < 0.05) increase in the concentration of carotenoids in the cowpea, peanut and pumpkin leaves while in amaranth and sweet potato greens, thermal processing resulted in a significant (p < 0.05) decrease in the concentration of these nutrients. [ABSTRACT FROM AUTHOR]

Proximate composition, mineral content and the effect of traditional processing practices on the retention of ascorbic acid, riboflavin and thiamine were studied using amaranth, cowpea, peanut, pumpkin and sweetpotato leaves. Results of this study indicated that, crude protein, crude fat, carbohydrate and ash contents were in the range of 20.64--46.56 percent, 2.57--4.34 percent, 35.43--63.50 percent and 8.92--15.69 percent respectively. The mineral content per 100 g of fresh vegetables was in the range of 83.64--229.34 mg, 145.97--780.19 mg, 11.5--2l.31 mg, 43.02--110.30 mg, 0.96--5.90 mg and 0.40--2.24 mg for Ca, K, Na, Mg, Fe and Zn respectively. For ascorbic acid, riboflavin and thiamine, concentrations in 100 g of fresh vegetables were in the range of 43.78--89.00 mg, 0.62--1.71 mg and 0.09--0.30 mg respectively. The traditional processing practices of sun/shade drying and storing in ventilated containers resulted in a significant (P <0.05) decrease in ascorbic acid, riboflavin and thiamine for all vegetables. Conventional blanching and cooking for up to 15 minutes resulted in a significant (P <0.05) increase in riboflavin content in cowpea, peanut and pumpkin greens while in amaranth and sweetpotato leaves, thermal processing resulted in a significant (P <0.05) decrease in the vitamin. Based on the results of this study, the vegetables were good dietary sources of minerals, carbohydrate and protein. [ABSTRACT FROM AUTHOR]

The effect of blanching on the antinutritional content was studied in cabbage, turnip, collard, sweetpotato and peanut leaves. All the vegetables contained various amounts of phytic acid, tannic acid and/or oxalic acid. Tannic acid was found in largest amounts ranging from 1266.00 mg/100 g in cabbage to 491.00 mg/100 g in sweetpotato. Phytic acid content ranged from 0.31 mg/100 g in sweetpotato to 3.97 mg/100 g in collard. Oxalic acid was in trace amounts in cabbage and turnip; but high concentrations were found in sweetpotato (469.67 mg/100 g) and peanut greens (407.00 mg/100 g). Levels of both tannic acid and phytic acid were significantly (p < 0.05) reduced by conventional and microwave blanching methods while oxalic acid levels were not significantly (p < 0.05) reduced in most of the treatments by either of the blanching methods. In general, blanching is recommended as an effective method for reducing the antinutritional factors in green vegetables, however, further investigation on the heating times for both conventional and microwave blanching methods has been suggested. [ABSTRACT FROM AUTHOR]

Expectations of housing prices play an important role in real estate research. Despite their importance, obtaining a reasonable proxy for such expectations is a challenge. The existing literature on mortgage research either does not include housing expectation proxies in empirical models, or uses 'backward-looking' proxies such as past housing appreciation or time series forecasts based on past housing appreciation. This paper proposes to use the transaction prices of Case-Shiller housing futures as an alternative 'forward-looking' proxy. As an example, we compare the performances of four different expectation proxies in explaining mortgage default behavior. The loan level analysis shows that the futures based expectation proxy outperforms other proxies by having the highest regression model fit and being the only proxy that shows a significant negative effect on mortgage default behavior, as theory suggests. Out of sample predictions also show that futures have better prediction accuracy than other proxies. In addition, the paper shows that futures contain additional information that is not present in the backward-looking proxies. [ABSTRACT FROM AUTHOR]

Spatial filtering in various forms has become a popular way to address spatial dependence in statistical models (Griffith, 2003; Tiefelsdorf & Griffith, 2007). However, spatial filtering faces computational challenges for largenas the current method requires order of n3operations. This manuscript demonstrates how using iterative eigenvalue routines on sparse weight matrices can make filtering feasible for data sets involving a million or more observations and empirically estimates an operation count on the order of n1.1. Moreover, we show that filtering performs better, both statistically and numerically, for spatial weight matrices with more neighbours. Finally, we show that although filtering out spatial aspects of the data reduces bias in parameter estimates for the spatially lagged dependent variable DGP, it also filters out spatial aspects of interest such as spillovers. RÉSUMÉ le filtrage spatial, sous différentes formes, est devenu un moyen populaire de traiter la dépendance spatiale dans des modèles statistiques (Griffith, 2003; Tiefelsdorf & Griffith, 2007). Toutefois, le filtrage spatial doit relever aujourd'hui le défi de l'informatique, pour des valeurs ‘N’ élevées, la méthode actuelle nécessitant des opérations de l'ordre de N au cube. Le présent manuscrit démontre la faon dont l'emploi de programmes à valeur propre itérative sur des matrices à pondération creuse peut permettre la viabilité du filtrage pour des ensembles de données comportant un million d'observations, ou davantage, et effectue de faon empirique une évaluation du nombre d'opérations sur l'ordre de ‘N’. Nous démontrons également que le filtrage fonctionne mieux, tant sur le plan statistique que sur le plan numérique, pour des matrices à pondération spatiale comportant plus de voisins. Nous démontrons enfin que, bien que le filtrage d'aspects spatiaux des données réduise les distorsions des estimations de paramètres, il permet également de filtrer des aspects spatiaux pertinents, comme les débordements. EXTRACTO El filtrado espacial de diversas formas se ha convertido en una manera popular de tratar la dependencia espacial en modelos estadísticos (Griffith, 2003; Tiefelsdorf & Griffith, 2007). No obstante, el filtrado espacial se enfrenta a retos computacionales para N grande, ya que el método actual requiere un orden de operaciones de N al cubo. Este documento demuestra cómo la aplicación de rutinas de valores eigen iterativas a matrices de pesos escasos puede hacer posible la filtración para conjuntos de datos con un millón o más de observaciones, y estima empíricamente un conteo de operaciones sobre el orden de N. Asimismo, mostramos que el filtrado es más eficaz, tanto estadística como numéricamente, en matrices de pesos espaciales con más vecinos. Finalmente, mostramos que, aunque el filtrado de aspectos espaciales de los datos reduce la parcialidad en las estimaciones de parámetros, también filtra aspectos espaciales de interés, tales como los ‘spillovers’. 摘要: 各种形式的空间过滤法已成为解决统计模型空间依赖性的一种常用方法(Getis and Griffith, 2002; Griffith, 2003;以及Tiefelsdorf and Griffith, 2007)。然而, 空间过滤法在N较大时面临计算方面的挑战, 因为目前的方法要求N-立方阶操作。本文展示了针对稀疏权重矩阵使用迭代特征值例程如何能使一百万或更多的观测数据集的过滤成为可能, 并能凭经验估计N阶的操作计数。此外, 我们还展示, 对于有更多邻近值的空间权重矩阵来说, 无论从统计学角度还是数值角度看, 过滤性能都能得到改善。最后, 我们还展示, 虽然过滤掉数据的空间方位能减少参数估计的偏差, 但同时也会过滤掉有意义的空间方位, 例如外溢。 [ABSTRACT FROM AUTHOR]

The purpose of this article is to show the foundational place that communication theory and its practice occupies in functioning work systems. Design/methodology/approach - This paper defines the word communication in terms of the creation and interpretation of displays, describes what it means to have a theoretical foundation for a discipline, identifies and elaborates on the development driving force of human resource development (HRD), presents and explains a model of a work system in which HRD functions, and elaborates on the role, function, and place of communicative acts in the maintenance of the work system and the work of HRD professionals. Findings - The article posits that communication theory underlies the processes and activities of both scholars and practitioners of HRD. Finally, it argues that courses in communication theory and organizational communication are essential in the preparation of both scholars and practitioners. Research limitations/implications - Research on the vagaries of communication in work systems may need to focus on identifying the causes of more easily identified symptoms. Researchers must be constantly alert to the changing role of communication as both a symptom and a cause of effective and ineffective work system functioning. Practical implications - Since human resource development is applied, practiced, and used predominantly in work systems, sensitivity to the fundamental role that communication plays in work systems may allow HRD practitioners to take a communicative perspective in analyzing and solving problems. Originality/value - This article directs readers to the main, fundamental issue in organizations and highlights the central role of communication in the functioning and development of both the human resources and the work system. [ABSTRACT FROM AUTHOR]

The thermodynamic constraints for the operation of the water oxidizing Mn[sub 4]/Ca cluster within Photosystem II (PS II) are discussed. These are then examined in the light of the known redox chemistry of hydrated Mn-oxo systems and relevant model compounds. It is shown that the latest high resolution crystal structure of cyanobacterial PS II suggests an organization of the mono Ca tetranuclear Mn cluster that naturally accommodates the stringent requirements for successive redox potential constancy, with increasing total oxidation state, which the enzyme function imposes. This involves one region of the Mn[sub 4]/Ca cluster being dominantly involved with substrate water binding, while a separate, single Mn is principally responsible for the redox accumulation function. Recent high level computational chemical investigations by the authors' strongly support this, with a computed pattern of Mn oxidation states throughout the catalytic cycle being completely consistent with this interpretation. Strategies to design synthetic, biomimetic constructs utilizing this approach for efficient electrolytic generation of hydrogen fuel within artificial photosynthesis are briefly discussed. [ABSTRACT FROM AUTHOR]

Most spatial econometrics work focuses on spatial dependence in the regressand or disturbances. However, Lesage and Pace (2009) as well as Pace and LeSage2009 showed that the bias in β from applying OLS to a regressand generated from a spatial autoregressive process was exacerbated by spatial dependence in the regressor. Also, the marginal likelihood function or restricted maximum likelihood (REML) function includes a determinant term involving the regressors. Therefore, high dependence in the regressor may affect the likelihood through this term. In addition, Bowden and Turkington (1984) showed that regressor temporal auto-correlation hada non-monotonic effect on instrumental variable estimators. We provide empirical evidence that many common economic variables used as regressors (e.g., income, race, and employment) exhibit high levels of spatial dependence. Based on this observation, we conduct a Monte Carlo study of maximum likelihood (ML), REML and two instrumental variable specifications for spatial autoregressive (SAR) and spatial Durbin models (SDM) in the presence of spatially correlated regressors. Findings indicate that as spatial dependence in the regressor rises, REML outperforms ML and that performance of the instrumental variable methods suffer. The combination of correlated regressors and the SDM specification provides a challenging environment for instrumental variable techniques. We also examine estimates of marginal effects and show that these behave better than estimates of the underlying model parameters used to construct marginal effects estimates. Suggestions for improving design of Monte Carlo experiments are provided. [ABSTRACT FROM AUTHOR]

Using New Orleans foreclosure data, where each property has three appraisals (borrower, lender, and referee), we are able to investigate the factors affecting appraisal bias and accuracy for distressed properties. Unconditional analysis shows that on average lender appraisals are higher than referee appraisals, while borrower appraisals are lower than referee appraisals. Much of the bias could be explained by various client and appraiser characteristics. The relation between the client and the appraiser affects valuation bias. Customer employed appraisers tend to give more client friendly valuations than their court appointed counterparts. However, experienced and licensed appraisers render less biased valuations. The appraisal bias does not appear to depend on neighborhood and demographic characteristics. In addition, experienced and licensed appraisers provide materially more accurate valuations. Unlicensed, inexperienced appraisers have an error rate approximately four times worse than licensed, experienced appraisers. [ABSTRACT FROM AUTHOR]