Testing for Interaction in Binary Logit and Probit Models: Is a Product Term Essential?

Political scientists presenting binary dependent variable (BDV) models often hypothesize that variables interact to influence the probability of an event, Pr( Y ). The current typical approach to testing such hypotheses is (1) estimate a logit or probit model with a product term, (2) test the hypothesis by determining whether the coefficient for this term is statistically significant, and (3) characterize the nature of any interaction detected by describing how the estimated effect of one variable on Pr( Y ) varies with the value of another. This approach makes a statistically significant product term necessary to support the interaction hypothesis. We show that a statistically significant product term is neither necessary nor sufficient for variables to interact meaningfully in influencing Pr( Y ). Indeed, even when a logit or probit model contains no product term, the effect of one variable on Pr( Y ) may be strongly related to the value of another. We present a strategy for testing for interaction in a BDV model, including guidance on when to include a product term.     

A Prospective,Longitudinal Examination of the Influence of Childhood Home and School Contexts on Psychopathic Characteristics in Adolescence

Much of the existing research examining etiological contributors to psychopathic characteristics considers only biological and physiological deficits, with little consideration given to contextual factors that may play a role in their development. This prospective, longitudinal study examined the influence of childhood home and school environments on adolescent psychopathic characteristics among 390 youth (50.5% female; 46.2% Black/African American, 44.9% Hispanic/Latino, 6.9% Asian or Native American/Alaska Native, and 2.1% Non-Hispanic White). Specifically, this study examined (1) the effect of home chaos and poor parental monitoring on adolescent primary and secondary psychopathy and callous-unemotional traits through the lens of multiple reporters, and (2) whether classroom climate quality across three years of childhood moderated these relationships. The results indicated that delinquency and home chaos in childhood were related to primary psychopathy in adolescence and that exposure to higher quality classroom climates across childhood acted as a buffer by mitigating the negative relationship between parental monitoring in childhood and secondary psychopathy in adolescence. These findings have implications for designing interventions to mitigate the manifestation of youth psychopathy.     

The Potential Protective Role of Peer Relationships on School Engagement in At-Risk Adolescents

Negative outcomes associated with adverse childhood experiences are well established, but little is known about protective factors that could promote positive adjustment among high-risk youth. This study examined the potential protective role of positive peer relationships in the association between adverse childhood experiences and school engagement among at-risk adolescents. Data were collected prospectively from birth until age 16 from 831 diverse adolescents (52.6% female; 54% African American, 24% Caucasian) who were at-risk for family violence and their caregivers. The significant and negative associations between adversities and school engagement outcomes at age 16 were mitigated by peer intimacy and companionship and exacerbated by peer conflict. The findings underscore the importance of fostering positive peer relationships for improving school engagement among at-risk adolescents.     

Improving Policy Effectiveness: Land Use Planning in a Devolved Polity

Improving public policy efficiency and effectiveness in land use planning is an established priority on the prevailing political agenda in the UK. Practical measures to enhance policy formulation in local land use development plans in Scotland offer an interesting case study of an attempt to improve policy consistency, and to secure efficiency gains in policy authorship. This article considers the specific focus on the drafting stage of public policy‐making drawing on insights provided by research into the production of model policies in Scotland. It questions the extent to which such an initiative will promote a more robust public policy‐making discipline in light of the policy cycle. The discussion of the case study illustrates a practical attempt by central government to enhance public policy‐making at the local level, while raising questions about the dangers of invoking a technocratic and instrumentalist approach to policy analysis.     

Devolution and the Social Welfare of Elderly Immigrants: Who Will Bear the Burden?

Growing ethnic diversity translates into rising numbers of individuals facing socioeconomic disadvantage, creating a context in which detailed examinations of public policy are critical for understanding the health care needs of immigrant populations in the United States. Although many scholars document the link between social disadvantage and increased morbidity and mortality, additional analyses are needed to identify specific public policies associated with decreased access to social goods and public services. The implications of the latest welfare bill, the Personal Responsibility and Work Reconciliation Act of 1996, on the health and social welfare of the aging Hispanic population provides a unique opportunity for such inquiry. On the basis of demographic trends and recent analyses of data from the Hispanic Established Populations for Epidemiologic Study of the Elderly, the results suggest that older, Mexican–origin immigrants are likely to become an even greater administrative responsibility of state and local governments.     

Trust: Why and How Historians Should Study It

Recent scholarship has examined the decline of trust between citizens and the elected representatives, which is seemingly a hallmark of contemporary Western democracies. But the problem is not new. This study draws on newspaper accounts to trace the accumulation and erosion of trust in the Scullin federal Labor government, during its early months. Elected on 12 October 1929, James Scullin's government was expected to resolve the long‐running New South Wales’ miners’ strike; his deputy, E.G. Theodore, promised Labor would return the miners to work on pre‐stoppage conditions. The promise was undeliverable. The lockout dragged on through Scullin's first months in office, with the miners refusing to work on reduced wages and the government unable to deliver on Theodore's pledge. By the end of January 1930, the government's trust relations with its core constituency had unraveled. This case study illustrates how trust is made and unmade through complex relations between individuals, and between individuals and institutions.     

Detection of drugs in saliva of impaired drivers

This study examined the feasibility of detecting drugs using saliva samples obtained from impaired drivers. Screening procedures on 1- to 2-mL samples were for cannabinoids, volatiles, benzodiazepines, and other acidic/neutral/basic drugs. Methodology consisted of enzyme multiple immunoassay technique (EMIT) and temperature programmed gas chromatography with confirmation by gas chromatography/mass spectrometry (GC/MS). Fifty-six samples were obtained from drivers arrested for suspicion of impaired driving. Other than alcohol, the major drugs detected were cannabinoids and diazepam. Cocaine was found in one case.