Toward an interdisciplinary model of barriers to nuclear arms control

The nuclear arms race is a powerful phenomenon with political, technical, historical, economic, and psychological dimensions. Most analyses concentrate on the political, technical, or historical dimensions to the neglect of the economic and psychological. This article seeks to correct this neglect, arguing that serious barriers to arms control arise from economic and psychological forces.Richard W. Mansbach critiques the article from the perspective of a political scientist. The authors rebut.     

The Road Not Taken? Changes in Welfare Entry During the 1990s*

Objective. This article examines how welfare entry rates changed during the 1990s, and also assesses whether changes in entry rates are accompanied by improvements in the circumstances of families that choose not to receive welfare. Methods. This analysis uses data from the 1990 and 1996 panels of the Survey of Income and Program Participation to identify three cohorts of low‐income single mothers who are potentially eligible for welfare but are not receiving benefits. Multivariate (competing risk) regression models and decomposition techniques are used to identify the factors responsible for changes in welfare entry patterns over the 1990s. Results. We find that welfare entry rates declined during the 1990s with the largest declines coming toward the end of the decade. Neither changes in the characteristics of low‐income single mothers nor improvements in the economy directly account for this shift. Rather, the introduction of new policies like time limits, full‐family sanctions, and family caps under welfare reform, along with unmeasured factors such as changes in attitudes toward work and welfare, account for the drop in welfare entry rates. The analysis also shows that declining entry rates are not accompanied by substantial improvements in the circumstances of low‐income single mothers who are not on welfare. Conclusions. Welfare reform policies adopted during the 1990s reduced entry into welfare, but single mothers who stayed off welfare remained in precarious economic circumstances.     

The perfect storm

When politicians fail to agree, very often it is the poorest who suffer most. More than 25 million additional children could go hungry through the failure of Copenhagen, says Gerald C. Nelson of the International Food Policy Research Institute. As crop yields decline, the calories available per person in sub-Saharan Africa will decline by 21%.     

Examining the impact of family services on homeless children

This study examined the impact on children of services delivered through a collaborative initiative designed to provide supports to working poor families who are homeless or at immediate risk of becoming homeless. Overall, a number of positive findings can serve to inform the development of promising intervention strategies for children in homeless families and highlight areas for further research. Along with improved housing status, there was a statistically significant improvement in the economic self‐sufficiency of the families served, regardless of whether they completed the full programme cycle. In addition, youth self‐report data indicated significant improvements in externalizing and internalizing behaviour. The ability to combine programme data with school data for participating children also made it possible to explore school performance outcomes. Although these results did not indicate a change in participants’ levels of attendance or reading performance, there was a statistically significant improvement in students’ math scores. Moreover, when participating children were compared with a group of students matched on their level of academic performance at baseline who had not received housing or homeless services, no significant differences were detected between groups post‐intervention, indicating that services may help reduce the risk of homeless students’ falling further behind their peers academically.     

Estimation of linear models for field experiments

General mixed linear models for experiments conducted over a series of sltes and/or years are described. The ordinary least squares (OLS) estlmator is simple to compute, but is not the best unbiased estimator. Also, the usuaL formula for the varlance of the OLS estimator is not correct and seriously underestimates the true variance. The best linear unbiased estimator is the generalized least squares (GLS) estimator. However, t requires an inversion of the variance-covariance matrix V, whlch is usually of large dimension. Also, in practice, V is unknown.

We presented an estlmator [Vcirc] of the matrix V using the estimators of variance components [for sites, blocks (sites), etc.]. We also presented a simple transformation of the data, such that an ordinary least squares regression of the transformed data gives the estimated generalized least squares (EGLS) estimator. The standard errors obtained from the transformed regression serve as asymptotic standard errors of the EGLS estimators. We also established that the EGLS estlmator is unbiased.

An example of fitting a linear model to data for 18 sites (environments) located in Brazil is given. One of the site variables (soil test phosphorus) was measured by plot rather than by site and this established the need for a covariance model such as the one used rather than the usual analysis of variance model. It is for this variable that the resulting parameter estimates did not correspond well between the OLS and EGLS estimators. Regression statistics and the analysis of variance for the example are presented and summarized.     

Inequality Constraints in the Univariate GARCH Model

To keep the conditional variances generated by the GARCH (p, q) model nonnegative, Bollerslev imposed nonnegativity constraints on the parameters of the process. We show that these constraints can be substantially weakened and so should not be imposed in estimation. We also provide empirical examples illustrating the importance of relaxing these constraints.     

Nursing home complaints: who's complaining and what's gender got to do with it?

Long Term Care Ombudsman Complaint data from one state's 261 nursing homes are examined in the study. We assessed differences between male and female groups, including chiefly residents, but also ombudsmen, the residents' relatives or friends, administrators, legal representatives, and others regarding types and rates of complaints as reported in the Administration on Aging (AoA) major categories of: Resident Care, Resident Rights, Administration, Quality of Life, and Complaints Not Against Facility. Proportionately, male residents lodged more complaints than females. Further, males complained more than females about Resident Rights violations and filed more Complaints Not Against Facility. Females lodged significantly more complaints about Care, Quality of Life and Administration.Thus, males were more likely to report technical, impersonal, and legalistic issues, than females, who were more likely to express concerns about personal care and socioemotional-environmental issues. Results yielded further evidence of gender differences in the patterns of resident complaints. Nursing home social workers are highlighted as agents in changing embedded stereotypes about residents and complaints.     

Underage college students' drinking behavior, access to alcohol, and the influence of deterrence policies. Findings from the Harvard School of Public Health College Alcohol Study

Underage drinking is a major problem at American colleges, but little is known about the extent of alcohol use in different student groups, in different colleges, and in states with different control policies. We used data from the 2001 and 3 previous Harvard School of Public Health College Alcohol Studies that compared responses of underage students with those of their 21-23-year-old peers. Underage students drank alcohol less frequently but were more likely to drink to excess when they drank. College educational efforts and deterrent policies were limited in their outreach, and half of underage students obtained alcohol very easily. Underage students in states with extensive laws restricting underage and high-volume drinking were less likely to drink and to binge drink. A majority of underage students supported increasing efforts to control underage drinking. The results suggest that additional policy efforts to control underage drinking may be effective and feasible.