Combining information for prediction in linear regression

This article deals with the prediction problem in linear regression where the measurements are obtained using k different devices or collected from k different independent sources. For the case of k=2, a Graybill-Deal type combined estimtor for the regression parameters is shown to dominate the individual least squares estimators under the covariance criterion. Two predictors ŷ _c and ŷ _p are proposed. ŷ _c is based on a combined estimator of the regression coefficient vector, and ŷ _p is obtained by combining the individual predictors from different models. Prediction mean square errors of both predictors are derived. It is shown that the predictor ŷ _p is better than the individual predictors for k≥2 and the predictor ŷ _c is better than the individual predictors for k=2. Numerical comparison between ŷ _c and ŷ _p shows that the former is superior to the latter for the case k=2.     

CAP Reforms in the 1990s and their Price and Welfare Implications: The Case of Wheat

We use a nonlinear commodity market model to assess, theoretically and empirically, the impacts of recent reforms of the CAP on prices and economic welfare in the EU. The empirical analysis is based on an aggregate structural econometric model of the EU wheat economy and its links to the rest of the world. Instability issues are also investigated. Impacts of CAP reforms on the variance of domestic and world prices are analysed and a Monte Carlo simulation is used to evaluate uncertainty in the model's welfare computations. Recent reforms led to a net welfare gain within the EU during the period 1993–2000. Additional budgetary costs are less than the welfare gains of consumers and producers. Producers gained as lower price support was overcompensated by additional direct payments.     

Mortgage credit conditions in the UK

It is widely perceived that credit conditions for UK consumers, particularly in the mortgage market, have been radically liberalized since the 1970s. The implications for the housing market and consumer spending have been important. This article by John Muellbauer draws on a 1997 paper by the author which examined data from the Survey of Mortgage Lenders to learn, from information about loan-to-value ratios of first-time buyers, classified by region, about changes in mortgage credit conditions. By controlling for economic and demographic influences on credit conditions, a single time-varying index of mortgage credit conditions was extracted from these SML data. This index rises in the 1980s, peaking towards the end of the decade. It retraces part of its rise in the early 1990s before rising again by 1995 to a level not far below the previous peak. The article considers whether more recent data suggest a further liberalisation of mortgage credit conditions. It draws on joint research with others to discuss possible implications for consumer spending, house prices, the volume of property transactions and mortgage defaults.     

The Evolution of the Social Contract

Two transitions in the evolution of the social contract are considered, the first from the dominance hierarchies of the great apes (used as a proxy for our prehuman ancestors) to the egalitarian political structure of non-sedentary hunter-gatherer bands, and the second, to the reintroduction of hierarchical institutions of governance, primarily a result of living in fixed settlements after the inception of agriculture. The first transition was a product of biological and cultural evolution, which brought about big brains, language, higher consciousness, and a lower rate of time preference that enabled early man to sustain an egalitarian social contract and thereby escape the domination that confronted his prehuman ancestors. The second transition was a product of cultural evolution alone. The high costs of enforcing the hunter-gatherer social contract caused it to break down and be replaced by hierarchy when the domestication of plants and animals gave rise to a sedentary existence and increased populations. However, it is shown that the very biological and cultural adaptations that made hunter-gatherer egalitarianism possible were a necessary foundation for the spontaneous creation of complex culture and the evolution of institutions that would once again eventually make freedom possible and economic prosperity possible.     

Temporary controls on capital inflows

During the past decade a number of countries imposed capital controls that had two distinguishing features: they were asymmetric, in that they were designed principally to discourage capital inflows, and they were temporary. This paper studies formally the consequences of these policies, calibrates their potential effectiveness, and assesses their welfare implications in an environment in which the level of capital inflows can be sub-optimal. In addition, motivated by the fact that these types of controls have often been left in place after the dissipation of the shock that lead to the controls being implemented, the paper evaluates the welfare cost of procrastination in removing these types of controls.     

Shopping from a List: International Studies of Consumer Online Experiences

In response to the growth of online shopping, consumer groups from around the world participated in two mystery shopping exercises. These exercises, conducted during the Christmas holiday seasons of 1998 and 2000, involved buying a variety of products from web sites located both domestically and abroad. A number of serious problems were identified within the research, especially lack of disclosure of key consumer information and failures in delivering goods and refunding consumers when goods were returned. The research has been used by consumer organizations to enhance consumer education and to lobby governmental and self-regulatory bodies for greater consumer protection in the online environment.     

A Study of Arbitrage Efficiency Between the FTSE‐100 Index Futures and Options Contracts

Despite the importance of the London markets and the significance of the relationship for market makers, little published research is available on arbitrage between the FTSE‐100 Index futures and the FTSE‐100 European index options contracts. This study uses the put–call–futures parity condition to throw light on the relationship between options and futures written against the FTSE Index. The arbitrage methodology adopted in this study avoids many of the problems that have affected prior research on the relationship between options or futures prices and the underlying index. The problems that arise from nonsynchroneity between options and futures prices are reduced by the matching of options and futures prices within narrow time intervals with time‐stamped transaction data. This study allows for realistic trading and market‐impact costs. The feasibility of strategies such as execute‐and‐hold and early unwinding is examined with both ex‐post and ex‐ante simulation tests that take into consideration possible execution time lags for the arbitrage trade. This study reveals that the occurrence of matched put–call–futures trios exhibits a U‐shaped intraday pattern with a concentration at both open and close, although the magnitude of observed mispricings has no discernible intraday pattern. Ex‐post arbitrage profits for traders facing transaction costs are concentrated in at‐the‐money options. As in other major markets, despite important microstructure differences, opportunities are generally rapidly extinguished in less than 3 min. The results suggest that arbitrage opportunities for traders facing transaction costs are small in number and confirm the efficiency of trading on the London International Financial Futures and Options Exchange. © 2002 John Wiley & Sons, Inc. Jrl Fut Mark 22:31–58, 2002     

Measuring Market Orientation: Exploring a Market Oriented Approach

This paper demonstrates that applications of existing approaches to measuring market orientation are myopic, non-comparative and over-reliant on the views of single respondents. Consequently, a multi-perspective, multi-informant approach for measuring market orientation is generated which focuses on gauging customers', competitors' and intra-organizational members' perceptions of the market orientation of an organization. To evaluate the psychometric properties of this approach an application of this design in a survey of manufacturing industry is subjected to tests for inter-rater reliability, scale reliability, content validity, criterion-related validity and construct validity. The conclusion of this evaluation is that the developed measure is both a reliable and valid means of gauging market orientation. The paper concludes with a series of implications for both theorists and practitioners.     

Rural Population Growth, 1950–1990: The Roles of Human Capital, Industry Structure, and Government Policy

Human capital raises rural incomes, but this effect is swamped by higher returns to human capital in urban markets. This leads to "brain drain" from rural areas. Populations grow more rapidly in rural counties that have a diversified employment base. Farm population grows faster (or declines more slowly) in counties with relatively high farm income, and nonfarm populations grow faster in counties with relatively high nonfarm income. However, higher farm incomes lead to slower nonfarm population growth and vice versa. Rural county government services financed by local taxes or debt have neutral or negative effects on population growth.