Simple main effects in factorial designs

For experimental designs with more than two factors, the concept of complexity of an interaction is introduced and used to extend the hypothesis testing strategies recommended by Keppel, Milliken & Johnson and others. The strategies are illustrated for the three-factor design.     

Robust sequential designs for approximately linear models

We consider the problem of the sequential choice of design points in an approximately linear model. It is assumed that the fitted linear model is only approximately correct, in that the true response function contains a nonrandom, unknown term orthogonal to the fitted response. We also assume that the parameters are estimated by M-estimation. The goal is to choose the next design point in such a way as to minimize the resulting integrated squared bias of the estimated response, to order n^-1. Explicit applications to analysis of variance and regression are given. In a simulation study the sequential designs compare favourably with some fixed-sample-size designs which are optimal for the true response to which the sequential designs must adapt.     

THE HAYEK HYPOTHESIS IN EXPERIMENTAL AUCTIONS: INSTITUTIONAL EFFECTS AND MARKET POWER

We report twelve market experiments utilizing a "seller market power" supply and demand structure where two of five sellers can unilaterally increase their profit by withholding supply. The data indicate that both the double auction and posted offer institutions result in traders extracting the bulk of the potential gains from exchange in the market; however, prices generally occur above the competitive equilibrium prediction. Market power in the form of strategic supply withholding does not appear to be responsible for the supra-competitive prices.     

Tobacco Farming and Public Health: Attitudes of the General Public and Farmers

The tobacco industry remains a formidable influence in thwarting tobacco control efforts, in part because industry leaders have raised policymaker and public concern about how tobacco control might negatively impact tobacco farmers. In this study, we interviewed a random, stratified sample of 528 tobacco farmers in the Southeast and 991 U.S. residents about issues related to tobacco farmers. We found that a majority of the U.S. public expressed the belief that U.S. taxpayers subsidized tobacco farmers. This belief, combined with the strong opposition to tobacco farmer subsidies (15 percent thought there should be subsidies), likely play a role in public attitudes toward tobacco farmers. At the same time, however, we found reasonably strong public support for efforts to help tobacco farmers transition to new enterprises, although the public underestimates tobacco farmer interest in diversification. For example, two of three Americans believe that the government should help farmers make a living other than growing tobacco and over half thought that taxpayers should help pay for such programs. These data illustrate potential common ground for elected officials to consider as they attempt to concomitantly address the needs of farmers and the interests of the public. Ultimately, if the interests of tobacco farmers can be made clearly to the general public, and vice versa, pro-health and pro-farmer policies might well become a reality     

Modeling the Modification of the Risk of Radon-Induced Lung Cancer by Environmental Tobacco Smoke

The presence of environmental tobacco smoke (ETS) in homes has been implicated in the causation of lung cancer. While of interest in its own right, ETS also influences the risk imposed by radon and its decay products. The interaction between radon progeny and ETS alters the exposure, intake, uptake, biokinetics, dosimetry, and radiobiology of those progeny. The present paper details model predictions of the various influences of ETS on these factors in the U.S. population and provides estimates of the resulting change in the risk from average levels of radon progeny. It is predicted that the presence of ETS produces a very small (perhaps unmeasurable) increase in the risk of radiation-induced tracheobronchial cancer in homes with initially very high particle concentrations for both active and never-smokers, but significantly lowers the risk in homes with initially lower particle concentrations for both groups when generation 4 of the lung is considered the target site. For generation 16, the presence of ETS generally increases the radon-induced risk of lung cancer, although the increase should be unmeasurable at high initial particle concentrations. The net effect of ETS on human health is suggested to be a complicated function of the initial housing conditions, the concentration of particles introduced by smoking, the target generation considered, and the smoking status of exposed populations. This situation precludes any simple statements concerning the role of ETS in governing the incidence of lung cancer in a population.     

DIFFERENTIAL ASSESSMENT OF FINANCIAL AND RELATIONSHIP DISTRESS: IMPLICATIONS FOR COUPLES THERAPY

The study examined the role of financial conflicts, problem-solving communication deficits, and global relationship distress among couples in marital therapy and couples seeking assistance at a nonprofit agency providing financial counseling services. Analyses comparing these two groups of couples with each other and with a third group of couples from the general community yielded a two-component model for differential assessment and intervention with couples experiencing financial concerns. Differences in findings for husbands and wives provided additional implications for effective interventions with these couples.     

Sex and Deviance: an Assessment of Major Sociological Variables*

This paper empirically examines the claim that many theories of deviance only have utility for explaining deviance committed by males because their conceptual development was tainted with inattention to females. Five variables representing the essence of major theories of deviant behavior are measured for a self-report sample of 1993 cases. Each variable is tested to determine how well it can account for deviance among females compared to males. In volume of deviance more males than females were classified as deviant but the underlying processes which the five theoretical variables address operated equally for members of both sexes. These findings support the position that the processes by which females come to commit deviance is similar to the processes for males. The findings suggest that exclusive focus on females is unlikely to yield more adequate explanations of female deviance.