Wal‐Mart and County‐Wide Poverty*

Objectives. This study seeks to identify the independent effect of Wal‐Mart stores on changes in U.S. family‐poverty rates at the county level. We draw on the contributions of a number of disciplines to enhance our understanding of the broader forces that influence poverty. Methods. A key innovation is that we estimate a two‐stage regression model, in which an instrument is created for new Wal‐Mart stores from a location equation; this reduces any potential endogeneity bias in the poverty‐change equation. In addition, we use spatial econometric methods to correct for spatial dependence bias. Results. After controlling for other factors determining changes in the poverty rate over time, we find that counties with more initial (1987) Wal‐Mart stores and counties with more additions of stores between 1987 and 1998 experienced greater increases (or smaller decreases) in family‐poverty rates during the 1990s economic boom period. Conclusions. Wal‐Mart creates both benefits and costs to communities in which the chain locates. These benefits and costs need to be weighed carefully by community decisionmakers in deciding whether to provide public subsidies to the chain.     

Can faster income growth reduce well-being?

In his book Luxury Fever: Why Money Fails to Satisfy in an Era of Excess (1999) economist Robert Frank describes a number of significant trends in the U.S., and to a lesser extent in other industrial economies, since the late 1970s: rapidly rising incomes, for those at the upper end of the income scale, increasing hours of work, and increased consumerism (share of consumption of ‘status goods’). We demonstrate that the first development can parsimoniously account for the latter two. Our novel specification of the utility function simultaneously incorporates a relative-consumption effect for status goods and non-homotheticity of preferences between status and non-status goods, and we also allow for endogenous labour–leisure choice. It is possible that well-being has declined, notwithstanding the faster income growth, or at least not risen pari passu with the growth in earnings. Comparisons are made with other studies, and policy implications briefly discussed.

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Estimation and Classification of BOLD Responses Over Multiple Trials

In this article, we model functional magnetic resonance imaging (fMRI) data for event-related experiment data using a fourth degree spline to fit voxel specific blood oxygenation level-dependent (BOLD) responses. The data are preprocessed for removing long term temporal components such as drifts using wavelet approximations. The spatial dependence is incorporated in the data by the application of 3D Gaussian spatial filter. The methodology assigns an activation score to each trial based on the voxel specific characteristics of the response curve. The proposed procedure has a capability of being fully automated and it produces activation images based on overall scores assigned to each voxel. The methodology is illustrated on real data from an event-related design experiment of visually guided saccades (VGS).     

Hypothesis testing, power and sample size determination for between group comparisons in fMRI experiments

Modern methods for imaging the human brain, such as functional magnetic resonance imaging (fMRI) present a range of challenging statistical problems. In this paper, we first develop a large sample based test for between group comparisons and use it to determine the necessary sample size in order to obtain a target power via simulation under various alternatives for a given pre-specified significance level. Both testing and sample size calculations are particularly critical for neuroscientists who use these new techniques, since each subject is expensive to image.     

Abortion on demand

The author celebrates the legalization of abortion in India as it will hopefully end the injury and death that often followed illegal abortion. However, she regards the law as incomplete since it gives no protection to the unwed mother except in the case of rape. Further, the law does not emancipate women because, except in instances of rape or contraceptive failure in a married woman, it is the doctor who decides on the abortion. If the woman is less than 18 years old or mentally incompetent, her legal guardian must give his consent.     

Small Sample Tests for Shape Parameters of Gamma Distributions

The introduction of shape parameters into statistical distributions provided flexible models that produced better fit to experimental data. The Weibull and gamma families are prime examples wherein shape parameters produce more reliable statistical models than standard exponential models in lifetime studies. In the presence of many independent gamma populations, one may test equality (or homogeneity) of shape parameters. In this article, we develop two tests for testing shape parameters of gamma distributions using chi-square distributions, stochastic majorization, and Schur convexity. The first one tests hypotheses on the shape parameter of a single gamma distribution. We numerically examine the performance of this test and find that it controls Type I error rate for small samples. To compare shape parameters of a set of independent gamma populations, we develop a test that is unbiased in the sense of Schur convexity. These tests are motivated by the need to have simple, easy to use tests and accurate procedures in case of small samples. We illustrate the new tests using three real datasets taken from engineering and environmental science. In addition, we investigate the Bayes’ factor in this context and conclude that for small samples, the frequentist approach performs better than the Bayesian approach.     

Challenging western hegemony through systematic study of cultural diversity: an undergraduate course on child development and culture

Traditional courses in developmental psychology treat the development of white, middle‐class European American children as normative. This approach offers an inaccurate representation of child development, displays a lack of sensitivity towards the cultural diversity of students, and fails to meet these students’ intellectual needs. This paper describes an attempt at rectifying this ethical, paradigmatic error in an undergraduate course on child development and culture. Key concepts at the interface of culture and development in cultural geographical zones that contrasted with the European‐American tradition were systematically treated, employing varied instructional strategies. The experience suggests that synthesizing a multicultural classroom with a multicultural syllabus compels students to confront their own intellectual ethnocentrism, diversifies intellectual experience and, for minority students, addresses an intellectual lacuna that they may not yet have articulated.     

Macro stress testing and resilience assessment of Indian banking

This study conducts policy-based macro stress testing of the Indian banking sector and also assesses its resilience towards compliance with BASEL norms with the aid of an empirical macro-financial model. It uses scenario analysis and quantitative techniques to capture the impact of macroeconomic stress on the stability of the Indian banks by evaluating financial soundness indicators (credit quality, quantity and quality of capital adequacy). The scenarios are generated through policy-based shocks vis-à-vis other external shocks. The results from the estimation of the model indicate a cointegrating relationship between credit quality and key macroeconomic variables including output growth rate, interest rate, money growth rate and exchange rate. The results of the scenario analysis reveal that the Indian banking sector remains largely sound in terms of total regulatory capital adequacy ratio as per current BASEL II and even BASEL III requirement. The results also show that expansionary monetary policy impacts credit quality and capital adequacy in a positive and significant manner via its effect on the economy’s growth rate.