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Model Specifications (model + specifications)
Kinds of Model Specifications Selected AbstractsRIGHT-TO-CARRY CONCEALED HANDGUNS AND VIOLENT CRIME: CRIME CONTROL THROUGH GUN DECONTROL?,CRIMINOLOGY AND PUBLIC POLICY, Issue 3 2003TOMISLAV V. KOVANDZIC Research Summary: "Right-to-Carry" (RTC) concealed-handgun laws mandate that authorities issue concealed handgun permits to qualified applicants. The supposition by those supporting the laws is that allowing private citizens to carry concealed handguns in public can reduce violent crime by deterring prospective criminals afraid of encountering armed civilians. Critics of the laws argue that violent altercations are more likely to turn deadly when more people carry guns. Whether the laws cause violent crime to increase or to decrease has become an important public policy question, as most states have now adopted such legislation. The present study evaluates Florida's 1987 RTC law, which prior research suggests plays a key role in the RTC debate. Specifically, we use panel data for 58 Florida counties from 1980 to 2000 to examine the effects on violent crime from increases in the number of people with concealed-carry permits, rather than before-after dummy and time-trend variables used in prior research. We also address many of the methodological problems encountered in earlier RTC studies. We present numerous model specifications, and we find little evidence that increases in the number of citizens with concealed-handgun permits reduce or increase rates of violent crime. Policy Implications: The main policy implication of this research is that there appears to be little gained in the way of crime prevention by converting restrictive gun carrying laws to "shall-issue" laws, although the laws might still prove beneficial by (1) eliminating arbitrary decisions on gun permit applications, (2) encouraging gun safety, (3) making permit holders feel safer when out in public, (4) providing permit holders with a more effective means of self-defense, and (5) reducing the costs to police departments of enforcing laws prohibiting unlicensed gun carrying. [source] Random perturbation methods applied to multivariate spatial sampling designENVIRONMETRICS, Issue 7 2001J. M. Angulo Abstract The problem of estimating a multivariate spatial random process from observations obtained by sampling a related multivariate spatial random process is considered. A method based on additive perturbation of the variables of interest is proposed for the assignment of degrees of relative importance to the variables and/or locations of interest in the design of sampling strategies. In the case where the variables involved have a multivariate Gaussian distribution, some theoretical results are provided to justify the method proposed; in particular, it is proved that the amount of information contained in the data on the perturbed variables of interest is never higher than that contained in the original variables of interest. These results and the application of the method are illustrated with an empirical study, showing the variation of the effects of perturbation on spatial sampling design configurations and related ratios of information for different degrees of dependence according to the model specifications. Copyright © 2001 John Wiley & Sons, Ltd. [source] Influence of Race on Household Residential UtilityGEOGRAPHICAL ANALYSIS, Issue 3 2000M William Sermons Residential location choice models are an important tool employed by urban geographers, planners, and transportation engineers for understanding household residential location behavior and for predicting future residential location activity. Racial segregation and residential racial preferences have been studied extensively using a variety of analysis techniques in social science research, but racial preferences have generally not been adequately incorporated into residential location choice models. This research develops residential location choice model specifications with a variety of alternative methods of addressing racial preferences in residential location decisions. The research tests whether social class, family structure, and in-group racial preferences are sufficient to explain household sensitivity to neighborhood racial composition. The importance of the interaction between the proportion of in-group race neighbors and other-race neighbors is also evaluated. Models for the San Francisco Bay metropolitan area are estimated and evidence of significant avoidance behavior by households of all races is found. The results suggest that social class differences, family structure differences, and in-group racial preferences alone are not sufficient to explain household residential racial preference and that households of all races practice racial avoidance behavior. Particularly pronounced avoidance of black neighbors by Asian households, Hispanic neighbors by black households, and Asian neighbors by white households are found. Evidence of a decrease in household racial avoidance intensity in neighborhoods with large numbers of own-race neighbors is also found. [source] Health state values for the HUI 2 descriptive system: results from a UK surveyHEALTH ECONOMICS, Issue 3 2005Christopher McCabe Abstract This paper reports the results of a study to estimate a statistical health state valuation model for a revised version of the Health Utilities Index Mark 2, using Standard Gamble health state preference data. A sample of 51 health states were valued by a sample of the 198 members of the UK general population. Models are estimated for predicting health state valuations for all 8000 states defined by the revised HUI2. The recommended model produces logical and significant coefficients for all levels of all dimensions in the HUI2. These coefficients appear to be robust across model specifications. This model performs well in predicting the observed health state values within the valuation sample and for a separate validation sample of health states. However, there are concerns over large prediction errors for two health states in the valuation sample. These problems must be balanced against concerns over the validity of using the VAS based health state valuation data of the original HUI2 valuation model. Copyright © 2004 John Wiley & Sons, Ltd. [source] Structure of the optimal income tax in the quasi-linear modelINTERNATIONAL JOURNAL OF ECONOMIC THEORY, Issue 1 2007Nigar Hashimzade H21; H24 Existing numerical characterizations of the optimal income tax have been based on a limited number of model specifications. As a result, they do not reveal which properties are general. We determine the optimal tax in the quasi-linear model under weaker assumptions than have previously been used; in particular, we remove the assumption of a lower bound on the utility of zero consumption and the need to permit negative labor incomes. A Monte Carlo analysis is then conducted in which economies are selected at random and the optimal tax function constructed. The results show that in a significant proportion of economies the marginal tax rate rises at low skills and falls at high. The average tax rate is equally likely to rise or fall with skill at low skill levels, rises in the majority of cases in the centre of the skill range, and falls at high skills. These results are consistent across all the specifications we test. We then extend the analysis to show that these results also hold for Cobb-Douglas utility. [source] Verification process and its application to network traffic simulation modelsJOURNAL OF ADVANCED TRANSPORTATION, Issue 3 2002Ryota Horiguchi This paper summarizes a standardized verification process for network traffic simulation models. After the general introduction of philosophy of verification, we explain detailed processes of the verification and its application to several well-known simulation models. "Verification" here means several examination tests of simulation models using virtual data on a simple network so as to confirm their fundamental functions. In the course of model development, the developers have to examine whether the model performance is consistent with the specifications that they intend and also with the well-authorized traffic engineering theory. Because of several constraints in putting the model specifications into the computer programming such as discretizing of time and space and simplifying vehicle behaviors to some degree, the intended model specifications may not be fully achieved in a computer. Therefore, we strongly recommend the verification before applying the models to a real network. [source] Auditor's Engagement Risk and Audit Fees: The Role of Audit Firm AlumniJOURNAL OF BUSINESS FINANCE & ACCOUNTING, Issue 9-10 2007Ilias G. Basioudis Abstract:, This study explores the effect of the association of audit firm alumni with their alma mater on audit prices. The tests indicate that there is a moderate reduction of up to 21% in the level of audit fee when alumni (i.e., former employees) of the incumbent audit firm sit on the client board of directors which is consistent with the engagement risk theory. This suggests that there is an ,alumni effect' in the market for audit services. The findings hold only in the large company segment of the market. The results are robust to different model specifications and alternative samples. The sample comprises all executive and non-executive directors who run the UK quoted companies and are simultaneously ICAEW qualified chartered accountants. The study's implications for the accounting profession and the regulators are also discussed. [source] Returns to Schooling and Bayesian Model Averaging: A Union of Two LiteraturesJOURNAL OF ECONOMIC SURVEYS, Issue 2 2004Justin L. Tobias Abstract., In this paper, we review and unite the literatures on returns to schooling and Bayesian model averaging. We observe that most studies seeking to estimate the returns to education have done so using particular (and often different across researchers) model specifications. Given this, we review Bayesian methods which formally account for uncertainty in the specification of the model itself, and apply these techniques to estimate the economic return to a college education. The approach described in this paper enables us to determine those model specifications which are most favored by the given data, and also enables us to use the predictions obtained from all of the competing regression models to estimate the returns to schooling. The reported precision of such estimates also account for the uncertainty inherent in the model specification. Using U.S. data from the National Longitudinal Survey of Youth (NLSY), we also revisit several ,stylized facts' in the returns to education literature and examine if they continue to hold after formally accounting for model uncertainty. [source] Does Private Money Buy Public Policy?JOURNAL OF ECONOMICS & MANAGEMENT STRATEGY, Issue 3 2007Campaign Contributions, Regulatory Outcomes in Telecommunications To what extent can market participants affect the outcomes of regulatory policy? In this paper, we study the effects of one potential source of influence,campaign contributions,from competing interests in the local telecommunications industry, on regulatory policy decisions of state public utility commissions. Our work is unique in that we test the effects of campaign contributions on measurable policy outcomes. This stands in stark relief against most of the existing literature, which examines potentially noisier measures of policy outcomes,such as the roll-call votes of legislators, to examine how private money may influence public policy. By moving to more direct measures of policy effects, and using a unique new dataset, we find, in contrast to much of the literature on campaign contributions, that there is a significant effect of private money on regulatory outcomes. This result is robust to numerous alternative model specifications. We also assess the extent of omitted variable bias that would have to exist to obviate the estimated result. We find that for our result to be spurious, omitted variables would have to explain more than five times the variation in the mix of private money as is explained by the variables included in our analysis. We consider this to be very unlikely. [source] Development of a multifunctional sales response model with the diagnostic aid of artificial neural networksJOURNAL OF FORECASTING, Issue 7 2005Stefania Pantelidaki Abstract This paper proposes an approach that models and forecasts sales through a flexible parametric response function (multifunctional), allowing for differentiated behavioural assumptions of the response determinants to be specified, and uses neural network modelling as a re-specification tool for the response model in order to improve forecasting performance. An initial experiment on a sample of sales data demonstrates feasibility and gives comparative insights via alternative model specifications. Copyright © 2005 John Wiley & Sons, Ltd. [source] Institutional Quality and the Gains from TradeKYKLOS INTERNATIONAL REVIEW OF SOCIAL SCIENCES, Issue 3 2006Axel Borrmann SUMMARY While theoretical models suggest that trade is likely to increase productivity and income levels, the empirical evidence is rather mixed. For some countries, trade has a strong impact on growth, whereas for other countries there is no or even a negative linkage. We examine one likely prerequisite for a welfare increasing impact of trade, that is, the role of institutional quality. Using several model specifications, including an instrumental variable approach, we identify those aspects of institutional quality that matter most for the positive linkage between trade and growth. We find that, above all, labour market regulation is the key to reducing trade-related adjustment costs. Market entry regulations, the efficiency of the tax system, the rule of law and government effectiveness do play a role too. In essence, the results demonstrate that countries with low-quality institutions do not benefit from trade. [source] Cost efficiency and value driver analysis of insurers in an emerging economyMANAGERIAL AND DECISION ECONOMICS, Issue 4 2009Attiea Marie This study investigated cost inefficiencies and its relationship with value drivers of insurers in United Arab Emirates (UAE). The study revealed that there were 21,33% cost inefficiencies in these insurers under different model specifications of stochastic frontier and DEA; value drivers such as lower leverage risk, lower capital risk significantly improved cost efficiencies consistent with Basel II norms; ROE positively influenced cost efficiencies with further trade off between increased profit margin, decreased asset utilization and/or reduced equity multiplier by the insurer managements to achieve a target-ROE; and the trend of cost efficiency was improving during 2000,2004. The study suggests that stock insurers could overcome their cost inefficiencies through adoption of efficient measures such as risk mapping of clients, risk prioritization besides ALM techniques. The study has direct implications for individual and institutional investors in making their portfolio investment decisions in insurance sector, policymakers, and regulators to closely monitor inefficient insurers consistent with Basel II norms. Copyright © 2008 John Wiley & Sons, Ltd. [source] Productive efficiency of English football teams,a data envelopment analysis approachMANAGERIAL AND DECISION ECONOMICS, Issue 5 2003Dieter J. HaasArticle first published online: 15 MAY 200 This paper investigates how close to their potential English Premier League Clubs play. Using a deterministic Data Envelopment Analysis Approach, the productive efficiency of 20 teams in the 2000/2001 season is measured and weaknesses of individual teams are disclosed. The sensitivity of results is analyzed with regard to different model specifications and variable combinations. Copyright © 2003 John Wiley & Sons, Ltd. [source] Do Higher Real Minimum Wages Lead to More High School Dropouts?AMERICAN JOURNAL OF ECONOMICS AND SOCIOLOGY, Issue 2 2009Evidence from Maryland Across Races We explore whether higher levels of the real minimum wage have differing effects on high school dropout rates across students of various races and ethnicities (whites, African Americans, Hispanics, and Asians). Using a panel of data across Maryland counties and annual observations in 1993,2004, we found higher real minimum wages to be associated with higher dropout rates for Hispanic students, but not for other races and ethnicities. We used a variety of model specifications and explanatory variables, including real income, the unemployment rate, teen pregnancy rates, and educational attainment among adults. Several of our findings are broadly consistent with commonly reported sociological observations regarding how behavioral choices may be affected by different levels across races and ethnicities of cultural integration of recent immigrants, family cohesiveness, the value placed on education, small business ownership, and hourly (vs. salaried) employment. [source] Price Premium and Foreclosure RiskREAL ESTATE ECONOMICS, Issue 2 2006Seow Eng Ong Many previous studies identify loan, property, borrower and environmental factors that impact the probability of foreclosure. Implicit in these studies is the assumption that the property was purchased at fair value. We question this assumption based on several empirical findings regarding property value uncertainty. In contrast to previous research, we explicitly quantify the price premium from a hedonic pricing model. Using a comprehensive database of real estate transactions in Singapore during 1989,2000, we document a price premium associated with properties that are subsequently foreclosed based on actual sales transactions. In addition, we find that the premium paid at purchase significantly increases the probability of foreclosure. These results are robust and continue to hold after controlling for other property-specific factors, time-varying macroeconomic conditions, alternative model specifications and definitions of price premium. [source] Overconfident managers and external financing choiceREVIEW OF BEHAVIORAL FINANCE (ELECTRONIC), Issue 1 2010Masaya Ishikawa G30; G32 Abstract This study examines the relationship between managerial overconfidence and corporate financing decisions by constructing proxies for managerial overconfidence based on the track records of earnings forecasts in Japanese listed firms. We find that managers have the stable tendency to forecast overly upward earnings compared to actual ones and that their upward bias decreases the probability of issuing equity in the public market by about 4.7 percent per one standard error, which economically has the strongest impact on financing decisions. This tendency is observed when we employ alternative measures for managerial overconfidence and other model specifications. However, in private placements, the choice to offer equity is not always avoided by managers. This implies that managers place private equity with the expectation of the certification effect. Copyright © 2010 John Wiley & Sons, Ltd. [source] Is Post-War Economic Growth Exponential?THE AUSTRALIAN ECONOMIC REVIEW, Issue 2 2006Sören Wibe In this article, we argue that there are strong reasons for using linear instead of exponential models when analysing post-war economic growth. Incorrect model specifications will lead to misinterpretations of the underlying economic reality and to erroneous economic forecasts. Our argument is based on an empirical investigation of real GDP per capita growth in 25 OECD countries (and three country aggregates) during the post-war period using the Box-Cox transformation method. The conclusion is that per capita growth is generally (more or less) linear (and definitely not exponential) for the level of economic development represented by these countries. Based on this we argue that analyses of growth should use linear instead of exponential models. This change of model could give new insights into problems connected with economic growth. [source] FOREIGN NETWORKS AND EXPORTS: RESULTS FROM INDONESIAN PANEL DATATHE DEVELOPING ECONOMIES, Issue 4 2008Fredrik SJÖHOLM F10; F23; L10 Most firms and plants in developing countries produce only for the domestic market and few are able to export. One plausible hypothesis is that foreign networks decrease export costs and that plants with large amounts of such networks will be relatively likely to start exporting. We focus on two types of foreign networks: foreign ownership and imports of intermediate products. Our results suggest that plants in Indonesian manufacturing with any foreign ownership are substantially more likely to start exporting than wholly domestically owned plants. The results remain robust to alternative model specifications and after controlling for other plant characteristics. There is no effect on exports of imports of intermediate products. [source] THE YEN-DOLLAR EXCHANGE RATE AND MALAYSIAN MACROECONOMIC DYNAMICSTHE DEVELOPING ECONOMIES, Issue 3 2007Mansor H. IBRAHIM E30; F33; F40 This paper empirically assesses the effect of the yen-dollar exchange rate on selected macroeconomic variables, namely, real output, price level, and money supply, for Malaysia. The results, which are based on a vector autoregressive framework, suggest that variations in the yen-dollar rate can have significant influences on Malaysia's macroeconomic variables. More specifically, the yen-dollar depreciation leads to contraction in real GDP and money supply. These results are fairly robust to alternative model specifications. We believe that, apart from providing important insights into the interactions between the yen-dollar rate and domestic macroeconomic variables, our results contribute to the debate on choice of exchange rate regimes for Malaysia. [source] Specification Analysis of Option Pricing Models Based on Time-Changed Lévy ProcessesTHE JOURNAL OF FINANCE, Issue 3 2004Jing-zhi Huang We analyze the specifications of option pricing models based on time-changed Lévy processes. We classify option pricing models based on the structure of the jump component in the underlying return process, the source of stochastic volatility, and the specification of the volatility process itself. Our estimation of a variety of model specifications indicates that to better capture the behavior of the S&P 500 index options, we need to incorporate a high frequency jump component in the return process and generate stochastic volatilities from two different sources, the jump component and the diffusion component. [source] Modeling dependencies between rating categories and their effects on prediction in a credit risk portfolioAPPLIED STOCHASTIC MODELS IN BUSINESS AND INDUSTRY, Issue 3 2008Claudia Czado Abstract The internal-rating-based Basel II approach increases the need for the development of more realistic default probability models. In this paper, we follow the approach taken in McNeil A and Wendin J 7 (J. Empirical Finance 2007) by constructing generalized linear mixed models for estimating default probabilities from annual data on companies with different credit ratings. The models considered, in contrast to McNeil A and Wendin J 7 (J. Empirical Finance 2007), allow parsimonious parametric models to capture simultaneously dependencies of the default probabilities on time and credit ratings. Macro-economic variables can also be included. Estimation of all model parameters are facilitated with a Bayesian approach using Markov chain Monte Carlo methods. Special emphasis is given to the investigation of predictive capabilities of the models considered. In particular, predictable model specifications are used. The empirical study using default data from Standard and Poor's gives evidence that the correlation between credit ratings further apart decreases and is higher than the one induced by the autoregressive time dynamics. Copyright © 2008 John Wiley & Sons, Ltd. [source] Insider Trading Regulation and Market Quality: Evidence from American Depositary ReceiptsASIA-PACIFIC JOURNAL OF FINANCIAL STUDIES, Issue 3 2010Kee H. Chung G10; G38 Abstract We investigate the relation between insider trading law enforcement and stock market quality using a sample of American Depositary Receipts (ADR) over the period from 1998 to 2006. We show that ADR from countries that have enforced insider trading laws have better market liquidity and lower information asymmetry than ADR from countries that have not enforced insider trading laws. In addition, ADR from countries with insider trading law enforcement have greater price efficiency. Our results are robust to different estimation methods and alternative model specifications. We interpret these results as evidence that the enforcement of insider trading laws can effectively deter insider trading and enhance both market liquidity and price efficiency. [source] Corporate Diversification, Relatedness, and Firm Value: Evidence from Korean Firms,ASIA-PACIFIC JOURNAL OF FINANCIAL STUDIES, Issue 6 2008Sung C. Bae Abstract We examine the valuation effects of diversification activities for Korean firms by diversification type and the occasion of the Korean financial crisis. Employing a unique dataset of 2,894 firm-years for the entire manufacturing industries, we find that diversification by Korean firms on average decreases firm value but its effect varies by the type of diversification. While unrelated diversification erodes firm value, related diversification is associated with a non-negative effect on firm value. These valuation effects are more pronounced before the crisis than after the crisis. Our results also show an important role of a firm's affiliation to a large business group, known as chaebols, that related diversification by chaebol-affiliated firms comes with a significant value gain. We further find that the different valuation effects of unrelated and related diversification are closely related to a firm's ownership concentration and financial leverage. Our results are robust to different samples and regression model specifications. [source] | ||||||||||||||||||||||||||||