ESTIMATING A PARAMETER WHEN IT IS KNOWN THAT THE PARAMETER EXCEEDS A GIVEN VALUE

In some statistical problems a degree of explicit, prior information is available about the value taken by the parameter of interest, θ say, although the information is much less than would be needed to place a prior density on the parameter's distribution. Often the prior information takes the form of a simple bound, ‘θ > θ₁ ’ or ‘θ < θ₁ ’, where θ₁ is determined by physical considerations or mathematical theory, such as positivity of a variance. A conventional approach to accommodating the requirement that θ > θ₁ is to replace an estimator, , of θ by the maximum of and θ₁. However, this technique is generally inadequate. For one thing, it does not respect the strictness of the inequality θ > θ₁ , which can be critical in interpreting results. For another, it produces an estimator that does not respond in a natural way to perturbations of the data. In this paper we suggest an alternative approach, in which bootstrap aggregation, or bagging, is used to overcome these difficulties. Bagging gives estimators that, when subjected to the constraint θ > θ₁ , strictly exceed θ₁ except in extreme settings in which the empirical evidence strongly contradicts the constraint. Bagging also reduces estimator variability in the important case for which is close to θ₁, and more generally produces estimators that respect the constraint in a smooth, realistic fashion.     

The potential of a couples approach to employment assistance: results of a nonexperimental evaluation

We present findings from a nonexperimental evaluation of an employment program in which both partners in young, low-income, primarily African-American couples simultaneously participated. Mothers participating in the couples program had larger immediate gains in employment and earnings and decreases in TANF receipt following their exit from the program relative to mothers who received employment assistance as individuals. Fathers showed similar although weaker results. These immediate benefits appeared to be driven by higher rates of program completion among couples’ participants. Couples in which both partners completed the program experienced the largest quarterly earnings gains, and couples with greater earnings’ gains were more likely to still be together one year after the program ended. Mothers’ earnings gains eroded in the two years following program completion and many reported new pregnancies and problems with child care. We suggest directions for future programs and encourage future studies to consider the range of mechanisms associated with a couples focus, including potential motivational benefits and unintended consequences.

An evaluation of the rural development commission's redundant building grant

The Rural Development Grant operates the Redundant Building Grant which is designed to bring redundant buildings in certain areas into commercial activity. This paper outlines the results of a recent evaluation of the Grant largely based on contacts with more than 400 applicants in nine counties. This survey is used to explore five aspects of rural policy: property development; business performance; job creation; integrated rural development; and aspects of land use planning.     

Are Hearing Voices Networks Compatible with Cognitive Behavioural Therapy for Psychosis?

The most extensively evaluated intervention for auditory hallucinations is Cognitive Behavioural Therapy for Psychosis (CBTp), which is usually delivered in statutory settings by experienced clinicians. In contrast, peer support networks, such as the Hearing Voices Network (HVN), operate informally using peers to normalise and manage voices. This article compares these two approaches to identify points of synergy and difference. Its analysis suggests the two approaches share many features, but also deviate in important ways that could compensate for each other. Instead of competing with each other as might first be thought, they may actually be complementary. Further, HVN may align comfortably with the values and principles of social work. Social workers seeking to engage with voice hearers may be advised to study the underlying principles of each approach to guide the way in which they can capitalise on intervention opportunities to better assist voice hearers.     

The effects of school desegregation on mixed-race births

We find a strong positive raw correlation between black exposure to whites in their school district and the prevalence of later mixed-race (black-white) births, consistent with the literature on residential segregation and endogamy. However, that relationship is significantly attenuated by the addition of a few control variables, suggesting that individuals with higher propensities to have mixed-race births are more likely to live in desegregated school districts. We exploit quasi-random variation from court-ordered school desegregation to estimate causal effects of school desegregation on mixed-race childbearing, finding small to moderate effects that are largely statistically insignificant. Because the upward trend across cohorts in mixed-race childbearing was substantial, separating the effects of desegregation plans from secular cohort trends is difficult; results are sensitive to how we specify the cohort trends and to the inclusion of Chicago/Cook County in the sample. The fact that the addition of a few control variables substantially weakens the cross-sectional relationship between lower levels of school segregation and higher rates of mixed-race childbearing suggests that a substantial portion of the observed correlation is likely due to who chooses to live in places with desegregated schools. Researchers should be cautious about interpreting raw correlations between segregation—whether residential or school—and other outcomes as causal. Our results also point to the need to carefully explore specification of cohort effects in quasi-experimental designs for treatments where cumulative exposure is important.     

Is Chinese National Health Insurance Effective in the Face of Severe Illness? A Perspective from Health Service Utilization and Economic Burden

Over the past decade, health insurance coverage has expanded dramatically in China. Health insurance benefits, however, remain shallow or ambiguous. This study examines the effect of Chinese national health insurance policy on health service utilization and economic burden in urban settings using the Urban Resident Basic Medical Insurance Household Survey. We employ the Heckman selection model to correct for selection bias among hospital inpatients, and find that compared to individuals without health insurance, those with health insurance are more likely to be admitted to the hospital when their physicians recommended them to enter the hospital as inpatients. Health insurance is also associated with about 45.6 % decrease in out-of-pocket inpatient expenditures. Individuals with urban employee basic medical insurance see the largest decrease in economic burden, followed by individuals with urban resident basic medical Insurance, and those with new rural cooperative medical insurance.     

Anabolic-Androgenic Steroids and Condom Use: Potential Mechanisms in Adolescent Males

Previous research has revealed a significant bivariate relationship between anabolic-androgenic steroid (AAS) use and reduced condom use among adolescent boys. However, to date, no known studies have explored the psychological mechanisms that may explain this relationship. Thus, the current study sought to examine two possible mediators in the association between AAS and condom use: depressive symptoms and substance use. Data were extracted from a nationally representative sample of U.S. adolescents. Participants were 3,780 U.S. high school boys who responded to self-report items assessing a number of health behaviors, including symptoms of depression, substance use, AAS use, and use of condoms during their most recent act of intercourse. Both depression and substance use were significant mediators in the relationship between AAS and condom use. However, when these effects were contrasted, the indirect effect of substance use was significantly stronger in magnitude than the effect of depression. Although AAS use was associated with sexual risk behaviors among adolescent boys, significant variance in this relationship was accounted for by elevated levels of depression and substance use, with substance use demonstrating a particularly salient pathway.     

Predictors of treatment outcome in a child and adolescent psychiatry clinic: A naturalistic exploration

We present data on predictors of treatment outcome for 3200 consecutive referrals to a child and adolescent psychiatry clinic. Using Reliable Change Index (RCI) methodology, we divided children into those who, between intake and discharge, improved, stayed the same, or got worse according to clinician-rated impairment. Most predictors of improvement were related to parent variables (marital status, maternal anxiety, and ethnicity), while those associated with deterioration were tied to child status (extent of psychiatric comorbidity, history of placement in a self-contained classroom, and a prior trial of psychotropic medications). The implications of these findings for data-driven program development, clinic management, treatment planning, and systems of care are discussed.