Joint tests of non-nested models and general error specifications

This paper is concerned with joint tests of non-nested models and simultaneous departures from homoskedasticity, serial independence and normality of the disturbance terms. Locally equivalent alternative models are used to construct joint tests since they provide a convenient way to incorporate more than one type of departure from the classical conditions. The joint tests represent a simple asymptotic solution to the “pre-testing” problem in the context of non-nested linear regression models. Our simulation results indicate that the proposed tests have good finite sample properties.     

Portmanteau test for conditional heteroscedasticity, using ranks of squared residuals

Squared residual autocorrelations have been found useful in detecting departures from linearity in time series models. This is especially the case with data exhibiting heterogeneity in variances. A rank test is proposed which is much more robust than its parametric counterpart.     

Beyond recruitment: Predictors of differential participation in a national antihunger organization

Surprisingly little research has sought to explain differential participation after recruitment into social movement organizations (SMOs). This study examines the influence of several sets of predictors on participation by members of a national organization in the antihunger movement. The findings highlight the importance of incentive, ideological, and microstructural factors for differential participation and suggest that favorable perceptions of SMOs also promote participation. Final remarks address the implications of the findings for the social movement and voluntary organization literatures.     

Question Order Effects on Subjective Measures of Quality of Life1

The effects of question order on respondents' ratings of general and specific aspects of community life were assessed using data from separate mail surveys in Montana and Pennsylvania, The samples differed in locale, composition, and size and the relevant questions varied in number, format, and specific focus. Nevertheless, for both data sets the general question was more likely to be answered and more likely to receive positive responses when it was asked after—rather than before—the specific questions. There was some indication that carryover from the specific items to the general question responses were somewhat greater for those questions asked most recently and less for those asked earlier. Implications of these findings are discussed.     

Modeling for Risk Assessment of Neurotoxic Effects

The regulation of noncancer toxicants, including neurotoxicants, has usually been based upon a reference dose (allowable daily intake). A reference dose is obtained by dividing a no-observed-effect level by uncertainty (safety) factors to account for intraspecies and interspecies sensitivities to a chemical. It is assumed that the risk at the reference dose is negligible, but no attempt generally is made to estimate the risk at the reference dose. A procedure is outlined that provides estimates of risk as a function of dose. The first step is to establish a mathematical relationship between a biological effect and the dose of a chemical. Knowledge of biological mechanisms and/or pharmacokinetics can assist in the choice of plausible mathematical models. The mathematical model provides estimates of average responses as a function of dose. Secondly, estimates of risk require selection of a distribution of individual responses about the average response given by the mathematical model. In the case of a normal or lognormal distribution, only an estimate of the standard deviation is needed. The third step is to define an adverse level for a response so that the probability (risk) of exceeding that level can be estimated as a function of dose. Because a firm response level often cannot be established at which adverse biological effects occur, it may be necessary to at least establish an abnormal response level that only a small proportion of individuals would exceed in an unexposed group. That is, if a normal range of responses can be established, then the probability (risk) of abnormal responses can be estimated. In order to illustrate this process, measures of the neurotransmitter serotonin and its metabolite 5-hydroxyindoleacetic acid in specific areas of the brain of rats and monkeys are analyzed after exposure to the neurotoxicant methylene-dioxymethamphetamine. These risk estimates are compared with risk estimates from the quantal approach in which animals are classified as either abnormal or not depending upon abnormal serotonin levels.     

A Process for Incorporating Comparative Risk into Environmental Policymaking in Louisiana

The goal of Louisiana's 1990–1991 comparative risk project, also called the Louisiana Environmental Action Plan (LEAP), was to incorporate risk assessment into state environmental planning and policymaking. Scientists, government officials, and citizens were brought together to estimate the relative risk to human health, natural resources, and quality of life posed by 33 selected environmental issues. The issues were then ranked according to their relative estimated risks. It was hoped that this ranking of "comparative risks" would enable state policymakers to target the most important environmental problems and allocate scarce public resources more rationally and efficiently. As a result of the project, the governor issued an Executive Order forming a permanent Public Advisory Committee to continue this type of comparative risk assessment in Louisiana.     

Female Labor Force Participation in Urban and Rural China1

Abstract The objective of this study is to examine female labor force participation and its determinants in rural and urban China. The sociological literature has demonstrated that participation tends to increase in urban and industrialized places where women have higher levels of education and fewer children, where more workers are engaged in service pursuits, and where family structure is less traditional. With the use of data on counties and cities (N = 2,377) from the I-percent sample of the 1982 census of the People's Republic of China, it was found that female labor force participation is likely to rise in areas with increased agricultural employment, educational levels, proportion of female-headed households, and higher male-to-female sex ratios. Both the size of the service sector and the fertility rate had negligible effects on female labor force participation. Although, on average, rural places have slightly higher levels of female labor force participation, when other variables are controlled, urban places have a higher rate of female participation. In addition, the findings suggest that market factors (i.e., education) are more likely to determine the rate of female labor force participation in urban areas; whereas demographic and social factors (i.e., sex ratio and household structure) play a more important role in explaining the female labor force participation in rural counties.     

FAMILY THERAPISTS' RESPONSE TO AIDS: AN EXAMINATION OF ATTITUDES,KNOWLEDGE, AND CONTACT*

As the number of individuals and families impacted by AIDS continue to multiply, family therapists will increasingly be asked to become engaged in the challenge of caring for those affected. To date, little has been written in family therpy journals regarding the response of family therapists to this crisis. This paper represents an initial attempt to examine the atitudes of clinical members of the American Association for Marriage and Family Therapy toward AIDS and persons with AIDS. Included in the study are data regarding the therapists' contact with persons with AIDS, gays, and lesbians, and the impact of such contact on attitudes. Implications for future research, training, and treatment of those affected by AIDS are also provided.     

The Social Context of Police Lying

This is an analysis of the social context of normal police lies. We define lies as speech acts which the speaker knows are misleading or false, are intended to deceive, and where evidence to the contrary is known to the observer. Lies are relative to a moral context, and what an audience will accept. Lies include excuses, which deny full responsibility for an act, but acknowledge its immorality, and justifications, which accept responsibility but deny blame-worthiness. Police learn to lie and to carefully distinguish normal (or acceptable) lies from unacceptable lies, suggesting that lies are a part of a negotiated occupational order. We show how and why some types of lies are rewarded by police using ethnographic data from an 18 month field study of a large urban force. Lies can be of little issue, or become troublesome. We report and analyze two kinds of troublesome lies: case lies, recognized stories an officer utilizes in a courtroom or on paper to facilitate the conviction of a suspect, and cover stories, lies an officer tells in court, to supervisors, and on the job with the aim of providing a verbal shield or mitigation in the event of discipline. Both excuses and justifications are woven together in these vignettes. An example of a refusal to lie is used to illustrate some of the limits on lying as well organizational factors in lying. Some implications for official lying are also noted.