Modelling demand and supply influences on utilization: A flow demand model to predict hospital utilization at the small area level

This study outlines a model to predict hospital utilization at the small area level within a National Health Service (NHS) institutional context. The proposed approach departs from alternative analyses based on utilization flows of hospital care between a local population and a hospital. A flow demand model is outlined that relates flow demand to utilization flows; models the interaction between hospital supply and utilization of alternative hospitals; captures the process of demand for hospital care, with special attention given to the role of other health care sectors, to the organizational and institutional context of the hospital system and to geographic variations. The flow approach partly overcomes the problem of dealing with simultaneity of determination between supply and demand. A two-part econometric model suitable to estimate the flow demand model for prediction purposes is tested and applied to the Portuguese health care system. The results show the model to be robust and to provide key information for defining future hospital policies at the central level.     

The Tobit cointegrated vector autoregressive model: An application to the currency market

The Tobit cointegrated vector autoregressive model proposed in this study extends the existing methodology by allowing the censored variable to be nonstationary. The approach requires deriving the distribution of the cointegration rank test and simulating new critical values. The empirical application refers to the currency market. It has confirmed that the exchange rate is driven by four main forces: inflation, terms of trade, the perception of the country-specific risk, and the state of the currency market. Temporary disequilibria in the currency market arise not only from the “fundamental” factors, but also from the contagion effect.     

Spatial random utility model with an application to recreation demand

The paper examines the relevance of unobserved spatial dependence between individual decision-makers in the analysis of discrete choices. To incorporate spatial interdependencies in the behavioral analysis, we propose a spatial random utility model of recreation demand. The model combines the set-theoretic concept of spatial neighborhood, endogeneity of spatial interdependencies, and unobservable individual preferences. Our estimation procedure uses an efficient pseudo maximum likelihood estimator. We apply the model to the study of recreational travel demand in Iowa and evaluate the significance of unobserved spatial interdependencies between individual households in recreational travel choices.     

An Afriat Theorem for the collective model of household consumption

We provide a nonparametric ‘revealed preference’ characterization of rational household behavior in terms of the collective consumption model, while accounting for general individual preferences that can be non-convex. Our main result is the Collective Afriat Theorem, which parallels the well-known Afriat Theorem for the unitary model. First, it provides a characterization of collectively rational consumption behavior in terms of collective Afriat inequalities. Next, it implies the Collective Axiom of Revealed Preference (CARP) as a testable necessary and sufficient condition for data consistency with collective rationality. Finally, the theorem has some interesting testability implications. With only a finite set of observations, the nature of consumption externalities (positive or negative) in the intra-household allocation process is non-testable. The same non-testability conclusion holds for privateness (with or without externalities) or publicness of consumption. By contrast, concavity of individual utility functions (representing convex preferences) turns out to be testable. In addition, monotonicity is testable for the model that assumes all household consumption is public.     

Determinants of demand for green products: An application to eco-label demand for fish in Europe

In this paper, we confront the theoretical motivations of the consumption of eco-friendly products and the factors influencing the European perceptions regarding the fact that “fish caught using an environmentally friendly technique may carry a special label”. We take advantage of the recent integration of non-economic elements in the microeconomic analysis of consumers' behavior in order to highlight the factors leading to their demand for green products. Thanks to an original European survey on seafood product carried out on more than 5000 consumers, we test the influence of intrinsic motivation, information, localization and socio-economic factors on the demand for an eco-label for fish.Our results show a significant connection between the desire for eco-labeling and seafood features, especially the freshness of the fish, the geographical origin of the fish and the wild vs farmed origin of the fish. Moreover, we prove the major role played by the fish price. We also demonstrate that the ecological issue regarding fisheries is highly connected to consumer information, intrinsic motivation and socio-economic status: the typical “green fish consumer” is a young woman, well educated, well informed on the state of marine resources and not very trusting of the regulation of the fisheries. Consumers who are aware of the importance of marine resource preservation have the same profile.     

QUEST III: An estimated open-economy DSGE model of the euro area with fiscal and monetary policy

This paper develops a DSGE model for an open economy and estimates it on euro area data using Bayesian estimation techniques. The model features nominal and real frictions, as well as financial frictions in the form of liquidity-constrained households. The model incorporates active monetary and fiscal policy rules (for government consumption, investment, transfers and wage taxes) and can be used to analyse the effectiveness of stabilisation policies. To capture the unit root character of macroeconomic time series we allow for a stochastic trend in TFP, but instead of filtering data prior to estimation, we estimate the model in growth rates and stationary nominal ratios.     

Spatial dynamics and convergence: The spatial AK model

We study the optimal dynamics of an AK economy where population is uniformly distributed along the unit circle. Locations only differ in initial capital endowments. Spatio-temporal capital dynamics are described by a parabolic partial differential equation. The application of the maximum principle leads to necessary but non-sufficient first-order conditions. Thanks to the linearity of the production technology and the special spatial setting considered, the value function of the problem is found explicitly, and the (unique) optimal control is identified in feedback form. Despite constant returns to capital, we prove that the spatio-temporal dynamics, induced by the willingness of the planner to give the same (detrended) consumption over space and time, lead to convergence in the level of capital across locations in the long-run.     

Endogenous fluctuations in the demand for education

Abstract. Enrollment rates to higher education reveal a quite large variation over time which cannot be explained by productivity shocks alone. We develop a human capital investment model in an overlapping generations framework that features endogenous fluctuations in the demand for education. Agents are heterogeneous in their beliefs about future wage differentials. An evolutionary competition between the heterogeneous beliefs determines the fraction of the newborn generation having a certain belief. Costly access to information on the returns to education induces agents to use potentially destabilizing backward looking prediction rules. Only if previous generations experience regret about their human capital investment decisions, will agents choose a more sophisticated prediction rule that dampens the cycle. Access to information becomes key for stable flows to higher education. RID="*" ID="*"We would like to thank Cars Hommes, Florian Wagener, seminar participants at the University of Amsterdam, participants of the workshop on ‘Skill Needs and Labor Market Dynamics’ at the Wissenschaftszentrum Berlin für Sozialforschung (WZB) for helpful discussions, and an editor of this Journal and three anonymous referees for their comments. Tuinstra's research is supported by the Netherlands Organisation for Scientific Research (NWO) under a MaG-Pionier grant. Neugart acknowledges financial support from the German Ministry of Education. Parts of the research were done while Tuinstra was visiting the WZB and when Neugart was visiting CeNDEF. Correspondence to: The research for this paper was done while the first author was affiliated with the Wissenschaftszentrum Berlin für Sozialforschung.     

Inequality foundations of concentration measures: An application to the Hannah-Kay indices

The aim of this paper is to provide a connection between concentration and inequality. In particular, we show that the general entropy inequality indices are, among inequality measures, those consistent with the whole set of Hannah-Kay concentration indices. We isolate the inequality component underlying concentration measures, obtaining an explicit additive decomposition of the change in concentration into the change in its two components, i.e., inequality and the number of firms. This relationship proves to be valid for the whole set of Hannah-Kay concentration indices, and embodies as particular cases some others previously found in the literature. We are particularly grateful to Emilio Cerdá for helpful comments on the mathematical formulation of the paper. The second author also acknowledges support through the European Commission Project #ERBCHRXCT980248.     

A continuous time model of European growth,integration and technology diffusion: The role of distance

Economists have been devoting increasing attention to the diffusion process of knowledge in economic activities. However, the models till now developed concentrate mostly on the dynamics determined by the steady state, when dealing with the interaction among many countries. Instead, we present a non-linear model where explicitly formalize the disequilibrium as starting point. We evaluate theoretically and empirically, with a continuous time analysis applied to panel data, the integration process of some main European countries by considering a simultaneous interaction among output, technology and business services. In this process we take particular care of distance, as a strategic variable over time, and of the following consequences on the convergence to the steady state. On this subject we also show a closed form solution in presence of a linear constraint on technology among countries.     

Errors of aggregation and errors of specification in a consumer demand model: a theoretical note

Abstract .  Consumer demand models based on the concept of a representative or average consumer suffer from aggregation error. Misspecification of the underlying micro utility-maximizing model, which is virtually inevitable, also results in error. This note provides a theoretical investigation of the relationship between the two types of error. Misspecified expenditure support functions for demand systems at the micro level induce the same misspecified structure in the corresponding expenditure functions at the macro level, and the errors at the two levels are shown to be of similar order.     

Ecosystem services and regional development: An application to Sweden

This study carries out interregional comparisons of development and sustainable use of natural capital with and without inclusion of non-marketed ecosystem services. A simple dynamic model of an open economy shows that appropriate adjustment of conventional income accounts includes flow and stock components, but excludes explicit entrance of pollution. Calculations are made for Swedish regions and for two types of ecosystem services — pollution sequestration and recreational services — provided by three types of ecosystems: forests, agricultural landscape and wetlands. When comparing the adjusted and non-adjusted regional income accounts it is shown that the two measurements generate significantly different pictures of regional income and growth; regions that are traditionally considered as relatively less growth promoting are shown to hold important sources of wealth from natural capital, while counties that are rich in conventional accounts fall behind when adjusting for values of changes in natural capital.     

The choice of a foreign price measure in a Bayesian estimated new-Keynesian model for Israel

We estimate a small DSGE model by full information Bayesian techniques on the basis of Israeli data from 1995 to 2006. The model was first developed and estimated by means of classical GMM in Argov and Elkayam (2010), and since then it has been used at the Bank of Israel for monetary policy analysis. It is widely believed that in 2007 (out of sample year) as elsewhere worldwide, inflation rose in Israel due to high commodity prices in global markets. However, our baseline model attributes most of the high inflation in 2007 to supply shocks. One conjecture is that this model's result derives from the inappropriate original use of the unit value of imported consumer goods (which do not include unprocessed food and energy) as the main foreign price measure. We test this conjecture by re-estimating the model with various other foreign price measures that typically do reflect the global rise in commodity prices and compare the log-marginal likelihoods. We find that no other price measure outperforms the original choice in the sample period. Only the foreign trade-weighted CPI equals the performance of the original choice while improving the 2007 interpretation of inflation, and should therefore be considered the main foreign price measure. The proposed methodology for comparing the suitability of alternative measures for observable variables can be applied to any model with exogenous variables that are characterized by univariate equations.     

An emprical model of the demand for a varied diet

This study attempts to measure some aspects of the household's demand for a varied die by invesigaing how he number of individual foods consumed b he household is affeced b is preferences and food expendiure. A heoriical model suggesed b household production theory is adopted to empirical data from a cross-section of households. It is found that the number of individual foods consumed is strongly responsive to househjold expenditure on all foods.     

The US retail demand for fish products: an application of the almost ideal demand system

The main objective is to address the limitations of past US fish demand research through the development of a variation of the almost ideal demand system model for disaggregate fish products at the retail level. Price and expenditure elasticities, as well as elasticities of substitution between fish products and other protein commodities, determined from this work may be used in the context of fisheries management and market development and promotion. Results indicate that with the exception of shellfish, demand for the various fish products is relatively inelastic. Cross-price elasticities are generally moderate while expenditure elasticities are large and positive for fresh fish and shellfish. Demographic effects, especially geographical division, season, race, occupation, age–sex household composition, and price–income interaction, as a proxy for quality, are highly significant variables.     

Price determination and dynamic adjustments: An inverse demand system approach to meat products in the United States

In this study the process of retail meat price determination is depicted in the form of an inverse demand system taking into consideration the dynamic adjustments present in monthly consumption data. The general dynamic framework identifies both long run and short run effects in a systematic manner and allows direct estimation of the long run price and scale flexibilities that are consistent with theory. The empirical application based on monthly U.S. meat products data provides reasonable and promising results.The authors are senior econometrician, Department of Risk Management, TRS, American Express Co., Phoenix, and assistant professor, Department of Applied Economics, University of Minnesota, St. Paul, respectively. The work was performed when the first author was an assistant research scientist at the Center for Agricultural and Rural Development, Department of Economics, Iowa State University, Ames. Journal Paper No. J-15784 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 3109.     

Modelling the demand for housing over the life cycle

We model individual demand for housing over the life cycle, and show the aggregate implications of this behaviour. Individuals delay purchasing their first home when incomes are low or uncertain. Higher house prices lead households to downsize, rather than to stop being owners. Fixed costs (property transactions taxes) have important impacts on welfare (a wealth effect) and house purchase decisions (substitution effect). In aggregate, positive house price shocks lead to consumption booms among the old but falls in consumption for the young, and reduced housing demand; positive income shocks lead to consumption booms among the young and increased housing demand.     

An application of maximum entropy estimation: the demand for meat in the United Kingdom

In many econometric studies of demand relationships the design matrix is frequently subject to severe collinearity. In this paper the Generalized Maximum Entropy methodology is introduced and used to estimate a set of demand relationships. The ability of Generalized Maximum Entropy to estimate economic relationships that are typically subject to a high degree of collinearity among the explanatory variables, thus potentially causing traditional methods of estimation to be unreliable, is explained. The results derived by this alternative method of estimation, for a UK meat demand data set, are analysed and examined. The potential for this emerging estimation methodology is discussed.