Dynamic Savings Decisions in Agricultural Environments With Incomplete Markets

We develop a methodology for examining savings behavior in rural areas of developing countries that explicitly incorporates the sequential decision process in agriculture. The approach is used to examine the relative importance of alternative forms of savings in the presence and absence of formal financial intermediaries. Our results, based on stage-specific panel data from Pakistan, provide evidence that the presence of financial intermediaries importantly influences the use of formal savings and transfers for income smoothing. We also find that there are significant biases in evaluations of the savings-income relationship that are inattentive to the within-year dynamics of agricultural production.     

The Modeling and Seasonal Adjustment of Weekly Observations

Several important economic time series are recorded on a particular day every week. Seasonal adjustment of such series is difficult because the number of weeks varies between 52 and 53 and the position of the recording day changes from year to year. In addition certain festivals, most notably Easter, take place at different times according to the year. This article presents a solution to problems of this kind by setting up a structural time series model that allows the seasonal pattern to evolve over time and enables trend extraction and seasonal adjustment to be carried out by means of state-space filtering and smoothing algorithms. The method is illustrated with a Bank of England series on the money supply.     

Rail safety and rail privatization

Privatisation of the state-owned British railway system was completed in 1997. The following 6 years saw four serious fatal train accidents, leading to 49 deaths. These were the train collisions at Southall in 1997 and Ladbroke Grove in 1999, each caused by trains passing red signals, and the derailments at Hatfield in 2000 and Potters Bar in 2002, each caused by defective track. Has safety been compromised by the sell-off of the railways? Andrew Evans looks at the evidence and asks has privatisation led to more accidents?     

Evaluation of multilevel decision trees

The evaluation of decision trees under uncertainty is difficult because of the required nested operations of maximizing and averaging. Pure maximizing (for deterministic decision trees) or pure averaging (for probability trees) are both relatively simple because the maximum of a maximum is a maximum, and the average of an average is an average. But when the two operators are mixed, no simplification is possible, and one must evaluate the maximization and averaging operations in a nested fashion, following the structure of the tree. Nested evaluation requires large sample sizes (for data collection) or long computation times (for simulations).     

The exponential distribution analog of the Grubbs–Weaver method

Abstract

Grubbs and Weaver (1947 Grubbs, F. E., and C. L. Weaver. 1947. The best unbiased estimate of population standard deviation based on group ranges. Journal of the American Statistical Association 42 (238):224–41. doi: 10.2307/2280652.[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) suggest a minimum-variance unbiased estimator for the population standard deviation of a normal random variable, where a random sample is drawn and a weighted sum of the ranges of subsamples is calculated. The optimal choice involves using as many subsamples of size eight as possible. They verified their results numerically for samples of size up to 100, and conjectured that their “rule of eights” is valid for all sample sizes. Here we examine the analogous problem where the underlying distribution is exponential and find that a “rule of fours” yields optimality and prove the result rigorously.     

Visualization for Large‐scale Gaussian Updates

In geostatistics and also in other applications in science and engineering, it is now common to perform updates on Gaussian process models with many thousands or even millions of components. These large‐scale inferences involve modelling, representational and computational challenges. We describe a visualization tool for large‐scale Gaussian updates, the ‘medal plot’. The medal plot shows the updated uncertainty at each observation location and also summarizes the sharing of information across observations, as a proxy for the sharing of information across the state vector (or latent process). As such, it reflects characteristics of both the observations and the statistical model. We illustrate with an application to assess mass trends in the Antarctic Ice Sheet, for which there are strong constraints from the observations and the physics.     

Gambling Behavior of Student-Athletes and a Student Cohort: What are the Odds?

This study investigated the prevalence of gambling, gambling related NCAA violations, and disordered gambling in student-athletes (n = 736) with a comparison cohort of students (n = 1,071) at four universities. Student-athletes reported similar rates of gambling frequency, use of a bookmaker, and disordered gambling as students. After accounting for demographic differences, student-athletes were less likely to engage in sports wagering than students. Several risk factors for disordered gambling were identified, including being male and reporting at least one parent with a history of gambling problems. These findings suggest that problems associated with gambling are a university-wide issue with student-athletes meriting additional attention because of implications for the integrity of intercollegiate sports. Improved prevention and intervention efforts for collegiate gambling are recommended.     

'The grit in the oyster': Community development workers in a modernizing local authority

This article offers a brief overview of the challenges facingUK local authorities, including the need to enhance public participationin decision making and service delivery, improve service performanceand increase partnership working. It explores the potentialcontribution of community development work to meeting thesechallenges, drawing on a case study of one UK county council.The essential tensions and conflicts in the role of communitydevelopment workers in a local authority are highlighted, showinghow the modernization process introduced by the New Labour governmentis adding further layers of complexity and ambiguity.     

Rurality and Income Inequality in the United States, 1975–2015

Recent events have focused attention on the perceived widening of the economic divide between urban and rural areas, and on the continued rise of national income inequality. We demonstrate that, in fact, the average income gap between urban (metropolitan) and rural (nonmetropolitan) households has not risen over the past 40 years, and makes virtually no contribution to national income inequality. Rising national inequality is driven by rising inequality within both urban and rural America, not by an urban/rural divergence. As is well known, the growing dispersion of household money income is partly driven by rising wage inequality, particularly in urban areas. Less well recognized is the role played by other income sources. We show that a decline in the progressivity of the distribution of social security payments and cash transfers, and an increase in the regressivity of the distribution of retirement incomes, have jointly made a comparably large contribution to rising income inequality. At the same time, the share of income from self-employment has declined, particularly in rural America, and because self-employment income is very unequally distributed, its diminution has retarded the growth of rural inequality. In 2014–15, however, rural inequality increased, cutting the urban/rural inequality gap in half.