A Bayesian Multiple Comparison Procedure for Order-Restricted Mixed Models

A Bayesian hierarchical mixed model is developed for multiple comparisons under a simple order restriction. The model facilitates inferences on the successive differences of the population means, for which we choose independent prior distributions that are mixtures of an exponential distribution and a discrete distribution with its entire mass at zero. We employ Markov Chain Monte Carlo (MCMC) techniques to obtain parameter estimates and estimates of the posterior probabilities that any two of the means are equal. The latter estimates allow one both to determine if any two means are significantly different and to test the homogeneity of all of the means. We investigate the performance of the model-based inferences with simulated data sets, focusing on parameter estimation and successive-mean comparisons using posterior probabilities. We then illustrate the utility of the model in an application based on data from a study designed to reduce lead blood concentrations in children with elevated levels. Our results show that the proposed hierarchical model can effectively unify parameter estimation, tests of hypotheses and multiple comparisons in one setting.     

One little Lebanese cucumber is not going to break the bank: Price in the choice of fresh fruits and vegetables

This paper reports on empirical research into individual consumer behaviour in the context of fresh fruit and vegetable purchases. The discussion draws on research results from two studies conducted around the actual shopping process. The findings suggest that consumers' price response behaviour may not be consistent with that predicted by economic theory and that this could be significant at the aggregate level. The existence of 'acceptable price ranges' points to the presence of price thresholds within which consumers are relatively insensitive to price movements. Also of relevance is that the primary influence of the budget constraint may be at a broader level rather than at the level of choosing particular products.     

Tax Clientele Effects in the Term Structure of UK Interest Rates

This paper tests for tax clientele effects in the term structure of UK interest rates. Five empirical models of the term structure of interest rates, incorporating tax effects, are estimated with daily data covering the period 31 March, 1995 to 3 August, 1995. In May 1995, the British government announced its intention to eliminate the tax exemption on capital gains from government bonds, but subsequently in July 1995 backtracked on some of its initial proposals. This period therefore forms the basis of a crude natural experiment in the sense that it provides an opportunity to examine tax clientele effects 'before' and 'after' an event which should have levelled greatly the taxing of government bonds. The empirical analysis suggests large tax clientele effects. However, there is little evidence of tax-specific term structures of interest rates.     

The false promise of technological determinism: the case of enterprise resource planning systems

According to software vendors and consultants, Enterprise Resource Planning systems (ERPs) transform the nature, structure and management of work regardless of organisational context. This paper contests this technologically deterministic view of organisational change by demonstrating the role that discourse plays in the social construction of ERPs.     

SOME FACTORS INFLUENCING FAMILY EXPENDITURES FOR OUTDOOR RECREATION*

The work week is becoming shorter, family incomes are rising, and population is increasing. This provides more opportunity for outdoor recreation and probably increases the demand for such facilities and related services. This paper is directed to the user of outdoor recreation facilities and attempts to analyze some factors influencing user expenditures. A sample of families from Census tract areas with low to high median family incomes, a major part of a relatively large Standard Metropolitan Statistical Area, was interviewed to obtain the empirical information treated in this paper. Factors expected to influence annual expenditures for outdoor recreation were annual family income, age of head of household, education, race, distance to outdoor recreation facilities and time spent participating in outdoor recreation outside an urban area. The principal findings indicate that most people travelled relatively short distances to outdoor recreation sites, and that family income, education, distance to recreation facility and time spent were significantly related to annual family expenditures. The authors believe that increased demand for outdoor recreation will significantly influence additional development of people-oriented outdoor recreation facilities and services. LOCALISATION ET LOISIRS DE PLEIN AIR –La semaine de travail est en train de diminuer. les revenus des families s'élèvent et la population s'accroît. Tout cela procure des occasions supplémentaires pour les loisirs de plein air et probablement augmente la demande de biens de ce type, et de services divers. Cet article concerne ceux qui ont des loisirs de plein air et essaie d'analyser les facteurs influencant leur depenses. Un échantillon des families à partir des zones de recensement avec des revenus bas jusqu'aux revenus médians, la plus grande partie de la zone statistique métropolitaine type, a été interviewée dans le but d'obtenir I'information empirique décrite et analysée dans eel article. Les facteurs qui sont supposés influencer les dépenses annuelles directes de loisirs de plein air étaient le revenu familial annuel, l'âge du chef de famille, l'éducation, la race, la distance jusqu'aux lieux de loisirs et le temps passé en participant aux loisirs a l'intérieur de la zone urbaine échantillonnée. Les principales conclusions indiquent que la plupart des gens voyagent sur de courtes distances jusqu'aux installations de loisirs et que le revenu familial, l'éducation, la distance jusqu'aux lieux de loisir et le temps passé en loisirs sont relies d'une façon significative aux dépenses annuelles des families pour ce genre de loisirs. Les auteurs pensent qu'une demande croissante de loisirs de plein air contribuera, d'une façon significative au développement supplémentaire des services et installations des loisirs de plein air.     

Demand responsive transport: towards the emergence of a new market segment

This paper focuses on recent British experience with telematics-based Demand Responsive Transport (DRT) services in rural areas. In recent years, the ability of DRT concepts to provide efficient, viable transport services has been greatly enhanced by the use of transport telematics as demonstrated in a variety of environments across Europe. The success of British local authorities in winning substantial funding under the Rural and Urban Bus Challenge programmes for the implementation of DRT has resulted in widespread interest in flexible forms of transport. It is thus timely to evaluate the impact of this substantial investment. Drawing on the experience of a number of UK schemes, the paper assesses the reasons for the new-found success of what is becoming a relatively well-accepted mode by concentrating on a variety of factors including: service characteristics (particularly route flexibility, flexibility of booking method and pre-booking regime), emerging markets and the overall contribution of DRT to increased social inclusion and intermodality. Impediments to the development of DRT services are highlighted. The paper also discusses current research into the next generation of DRT services and concludes by identifying some key issues for policy-makers concerned with the future implementation of DRT services.     

Do Wages Rise or Fall Following Merger?*

This paper provides a systematic empirical analysis of the effects of merger and acquisition activity on profitability and firm‐level employee remuneration in the UK, using a specially constructed database for the period 1979–91. It finds that both profitability and wages rise following acquisition, and firms that merge within the same industry division experience larger increases in profitability and pay their workers higher wages than those engaged in unrelated acquisitions; i.e. in part, the result of an increase in the efficiency with which labour is used following related acquisition.     

Market Size and Economic Integration when Labor Markets are Unionized

The paper explores the effects of economic integration on trade, wages, and welfare when market sizes differ. A duopoly model with two‐way intraindustry trade in similar products and with unionized labor markets is employed. It is confirmed that, for a wide range of different relative market sizes, integration leads to higher wages, employment, and welfare. However, where market sizes differ widely, the reduction of trade barriers leads to a reduction of wages, employment, and—in some circumstances—welfare in the country with the large market.     

Some Economics of Integrated and Segmented Markets

For the purposes of the discussion in this paper, whether markets are integrated or segmented is endogenous and is determined by the interaction of demand parameters, tariffs, transportation costs, and arbitrage. Given certain restrictions, it is shown, in equilibrium, that policymakers choose tariffs to segment markets. The effects of trade liberalization (reducing all tariffs to zero) in an endogenous market structure framework are determined and compared to the existing literature. The results differ substantially, highlighting the importance of explicit modeling of costly arbitrage in imperfectly competitive models.