Statistical Decision Problems and Bayesian Nonparametric Methods

This paper considers parametric statistical decision problems conducted within a Bayesian nonparametric context. Our work was motivated by the realisation that typical parametric model selection procedures are essentially incoherent. We argue that one solution to this problem is to use a flexible enough model in the first place, a model that will not be checked no matter what data arrive. Ideally, one would use a nonparametric model to describe all the uncertainty about the density function generating the data. However, parametric models are the preferred choice for many statisticians, despite the incoherence involved in model checking, incoherence that is quite often ignored for pragmatic reasons. In this paper we show how coherent parametric inference can be carried out via decision theory and Bayesian nonparametrics. None of the ingredients discussed here are new, but our main point only becomes evident when one sees all priors—even parametric ones—as measures on sets of densities as opposed to measures on finite-dimensional parameter spaces.     

Asymptotic behaviour of tests for a unit root against an explosive alternative

We compare the asymptotic local power of upper-tail unit root tests against an explosive alternative based on ordinary least squares (OLS) and quasi-differenced (QD) demeaning/detrending. We find that under an asymptotically negligible initialisation, the QD-based tests are near asymptotically efficient and generally offer superior power to OLS-based approaches; however, the power gains are much more modest than in the lower-tail testing context. We also find that asymptotically non-negligible initial conditions do not affect the power ranking in the same way as they do for lower-tail tests, with the QD-based tests retaining a power advantage in such cases.     

DYNAMIC STATUS EFFECTS,SAVINGS, AND INCOME INEQUALITY

This article advances the hypothesis that the intensity of status preferences depends negatively on the average wealth of society (endogenous dynamic status effect), in accordance with empirical evidence. Our theory replicates the contradictory historical facts of an increasing saving rate along with declining returns to capital over time. By affecting the dynamics of the saving rate, the dynamic status effect raises inequality, thereby providing a behavioral mechanism for the observed diverse dynamics of income inequality across countries. In countries in which the dynamic status effect is strong (weak), inequality rises (declines) over time in response to a positive productivity shock.     

A Different Perspective on the Evolution of UK Income Inequality

This paper scrutinizes the conventional wisdom about trends in UK income inequality and also places contemporary inequality in a much longer historical perspective. We combine household survey and income tax data to provide better coverage of all income ranges from the bottom to the very top (and make our estimates available to other researchers). We make a case for studying distributions of income between tax units (i.e. not assuming the full income sharing that goes with the use of the household as the unit of analysis) for reasons of principle as well as data harmonization. We present evidence that income inequality in the UK is as least as high today as it was just before the start of World War 2.     

You should know better! Do health students have different risk attitudes to unplanned pregnancy and sexually transmitted diseases?

Because healthcare professionals are in the best position to assess, assist and educate those participating in risky sexual behaviour, understanding if (and how) their risk attitudes differ from the wider population is of vital importance. In this study, we explore university health students’ risk attitudes towards unplanned pregnancy and sexually transmitted diseases (STDs). We examine whether university students pursuing health-related degrees, who hypothetically should have more exposure to and understanding of the risks associated with unplanned pregnancy and STD, have more risk averse attitudes to sexual behaviour. We find that health students’ sexual attitudes are significantly more risk averse than those of their nonhealth peers in relation to STDs but not unplanned pregnancy. In line with previous research, age and no previous sexual history (virginity) appear to increase risk-averse attitudes to both unplanned pregnancy and STDs. Moreover, males and singles are more risk seeking in their sexual attitudes. These findings suggest that, because unplanned pregnancy and STDs are ongoing global issues, further research is warranted into the risk attitudes of those healthcare professionals most able to provide education and support for individuals participating in risky sexual behaviour.     

Expressive voting and two-dimensional political competition: an application to law and order policy by New Labour in the UK

There has been much debate regarding the electoral strategy adopted by New Labour in the lead-up to and then during their time in government. This paper addresses the issue from the perspective of left/right and liberal/authoritarian considerations by examining data on individual attitudes from the British Social Attitudes survey between 1986 and 2009. The analysis indicates that New Labour’s move towards the right on economic and public policy was the main driver towards attracting new centrist voters and could thus be labelled ‘broadly’ populist. The move towards a tougher stance on law and order was more ‘narrowly’ populist in that it was used more to minimise the reduction in support from Labour’s traditional base on the left than to attract new votes. The evidence presented provides support for an expressive theory of voting in that law and order policy was arguably used to counter alienation amongst traditional, left-wing Labour supporters.     

Fixed versus flexible election terms: explaining innovation in the timing of Canada’s election cycle

This paper argues that there is an efficiency gain underlying the recent adoption of legislation calling for a fixed 4-year governing term by the federal and most provincial governments in Canada. The efficiency gain arises from foreclosing an externality produced by the Canadian constitutional provision that sets a maximum length for a legislative term (5 years) while allowing the governing party (through the Governor General) to dissolve the House early. Because the opportunistic use of surprise can improve the governing party’s probability of winning, strategic choice can lead to elections being held at times that most disadvantage the incumbent’s rivals. Evidence from Canada is introduced suggesting that federal elections became less predictable through successive reductions in the campaign time given to competitors, thus raising the cost of this externality. The same reasoning suggests that the party most likely to propose this legislative innovation will be the party in opposition rather than in power and/or the new leader of an established party facing loss in the upcoming election. By fulfilling the fixed term even when it could benefit by calling the election early, the party establishes a precedent that raises the political cost to others of cancelling the fixed term legislation.     

The relationship between population growth and standard-of-living growth over 1870–2013: evidence from a bootstrapped panel Granger causality test

This paper examines the linkages between population growth and standard-of-living growth in 21 countries over the period of 1870–2013. We apply the bootstrap panel causality test proposed by Kónya (Econ Model 23:978–992, 2006), which accounts for both dependency and heterogeneity across countries. We find one-way Granger causality running from population growth to standard-of-living growth for Finland, France, Portugal, and Sweden, one-way Granger causality running from standard-of-living growth to population growth for Canada, Germany, Japan, Norway and Switzerland, two-way causality for Austria and Italy, and no causal relationship for Belgium, Brazil, Denmark, Netherlands, New Zealand, Spain, Sri Lanka, the UK, the USA, and Uruguay. Dividing the sample into two subsamples due to a structural break yields different results over the two periods of 1871–1951 and 1952–2013. Our empirical results suggest important policy implications for these 21 countries as the directions of causality differ across countries and time period.     

A General Method of Deriving the Inefficiencies of Banks from a Profit Function

This article develops a new method of estimating inefficiencies in joint production and shows that unlike the approaches utilized in the previous studies of inefficiency, this method maintains a consistent relationship between the error term of a profit function and the error terms of its price derivatives. A useful by-product of the method is a proof of a Hotelling-like lemma that relates stochastic input demand and output supply functions to stochastic profit functions. While the previous studies fit a single frontier to data on all firms, this paper estimates a frontier unique to every observed firm to allow each one to have a different potential of achieving maximal levels of profit. The new method is applied in the analysis of annual data, 1984–1989, for U.S. commercial banks. Both the analytical and numerical results of the paper show that the residual that the previous studies attribute to inefficiency includes the effects of excluded variables and of inaccuracies in the specified functional forms. Once accurate estimates of these effects are subtracted from the residual, the distortions in the measured inefficiencies should be considerably reduced. Consequently, this article considers how such estimates might be obtained.