Age at first birth, health, and mortality

The biodevelopmental view sees the readiness and soundness of the organism at the time of first birth as its prime link to health and survival years and decades later. It suggests an optimum age at first birth shortly after puberty. The biosocial view emphasizes social correlates and consequences of age at first birth that may influence health and survival many years later. It suggests that better health and survival come from delaying motherhood as long as possible, perhaps indefinitely. Analyses consistently find patterns more in keeping with the biosocial view in a U.S. national sample of women ages 25 through 95. The fitted curves show high levels of current health problems among women who first gave birth in or shortly after puberty. Problems drop steadily the longer that first birth was delayed, up to about age 34, then rise increasingly steeply, particularly after about age 40. For women currently of the same age, the ratio of health problems expected given first birth under age 18 versus around age 34 equals that from currently being 14 years older. Health problems rise steeply with length of having delayed beyond age 40. Mortality hazard also declines with having delayed first birth well beyond the end of puberty. The ratio of mortality hazard between mothers with teenage versus late first births equals that from a 10-year difference in current age. Comparison to nonmothers of similar age and race/ethnicity shows that the correlation of motherhood with health problems and mortality hazard switches from detrimental to beneficial with delay beyond about age 22.     

Substance use and social identity in the lesbian community

Although the study results report discrepancies in the rates of substance abuse in the lesbian community, the general consensus in the field of gay and lesbian studies is that these individuals, as a whole, have a higher rate of substance use. For this study, data were collected via the Internet on the use of drugs and alcohol, level of self-esteem, and degree of social identity in the lesbian community. A correlation analysis was used to determine if negative social identity within the lesbian community leads to low self-esteem that is reflected in higher rates of substance abuse. Though a positive relationship between social identity and self-esteem was determined, no significant correlation between negative social identity, low self-esteem, and substance use was determined. However, it is important to consider that respondents with higher levels of self-esteem reported more frequent use of specific drugs. That outcome in itself is an implication for further investigation.     

Rating methodological quality: toward improved assessment and investigation

Assessing methodological quality is considered essential in deciding what investigations to include in research syntheses and in detecting potential sources of bias in meta-analytic results. Quality assessment is also useful in characterizing the strengths and limitations of the research in an area of study. Although numerous instruments to measure research quality have been developed, they have lacked empirically-supported components. In addition, different summary quality scales have yielded different findings when they were used to weight treatment effect estimates for the same body of research. Suggestions for developing improved quality instruments include: distinguishing distinct domains of quality, such as internal validity, external validity, the completeness of the study report, and adherence to ethical practices; focusing on individual aspects, rather than domains of quality; and focusing on empirically-verified criteria. Other ways to facilitate the constructive use of quality assessment are to improve and standardize the reporting of research investigations, so that the quality of studies can be more equitably and thoroughly compared, and to identify optimal methods for incorporating study quality ratings into meta-analyses.     

How Many Balance Functions Does it Take to Determine a Utility Function?

Call b your balance function at wealth W if you are indifferent between W and a 50–50 lottery with outcomes x and b(x). Given one b, u is arbitrary on one side of W but then determined on the other. Given two b‘s, u is arbitrary between the two W′ s but then determined elsewhere. Additional properties of u restrict the b’s but do not ordinarily make u unique. Contradictions can occur. Given three b′ s, an algorithm is developed using minimal domains of definition that determines the relative utility of the W’s. If it is irrational, then the set S generated by applying all combinations of b’s to W′ s is dense and u is determined. If finitely many b’s are rationally related, then S is discrete, a further algorithm determines it, the values of u on S are equally spaced, and u is arbitrary between any two adjacent points of S but then determined elsewhere. Infinitely many balance functions determine u unless they are rationally related in a uniform way.JEL Classification: D81     

An Empirical Investigation of the Assumptions of Risk-Value Models

Do participants make decisions consistent with risk-value tradeoffs? One hundred and five undergraduate business students made risk and preference judgments about lottery pairs in a series of paper surveys. The data indicate that the participants’ responses were generally consistent with the key assumptions of risk-value models, but that some extensions of the theory would improve this consistency. In particular, we find that modifying the risk assumptions of the risk-value theory so they are consistent the concept of the reflection of the risk attitude in the domains of gains and losses increases the agreement between the theory and the participants’ responses.