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This paper outlines decomposition methods for assessing how exposure affects prevalence and cumulative relative risk. Let x denote a vector of exogenous covariates and suppose that a single dimension of time t governs two event processes T1 and T2. If the occurrence of the event T1 determines entry into the risk of the event T2, then subgroup variation in T1 will affect the prevalence T2, even if subgroups in the population are otherwise identical. Although researchers often acknowledge this phenomenon, the literature has not provided procedures to assess the magnitude of an exposure effect of T1 on the prevalence of T2. We derive decompositions that assess how variation in exposure generated by direct and indirect effects of the covariates x affect measures of absolute and relative prevalence of T2. We employ a parametric but highly flexible specification for baseline hazard for the T1 and T2 processes and use the resulting parametric proportional hazard model to illustrate the direct and indirect effects of family structure when T1 is age at first sexual intercourse and T2 is age at a premarital first birth for data on a cohort of non-hispanic white U.S. women.

Apres un rappel methodologique de l'analyse sequentielle, l'A. expose les forces et les faiblesses de cette technique. Il emet un jugement critique sur les avis de Abbott et Tsay a propos de l'application de l'analyse sequentielle aux carrieres professionnelles. En particulier, l'A. met l'accent sur la question de l'asymetrie des relations unissant les differentes sequences composant une carriere professionnelle. Ce probleme souleve la question des couts en jeu dans les transitions entre les sequences. L'A. defend la methode de l'analyse historique evenementielle et expose en quoi son avis diverge de celui d'Abbott et Tsay

This article addresses two questions: First, why is Black unemployment persistently higher than White unemployment? Second, how can this fact be reconciled with narrowing Black/White differentials in educational attainment, occupational position, and earnings? We show that the persistent racial gap in unemployment is due to differential access to employment opportunities by region, occupational placement, labor market segmentation by race, and labor market discrimination. Our findings showing that the racial gap in unemployment is greatest for college-educated men and are consistent with the view that Blacks still encounter barriers to employment in the labor market.

This article assesses the bias and fit of a hazard rate model by comparing predicted and nonparametric estimates of survivor probabilities. These comparisons also generate several diagnostic displays for event history data. We illustrate these diagnostic methods for several global and local hazard models using data on age at first marriage for women from the June 1980 Current Population Survey. Our results suggest that a nonproportional local Gompertz model performs better than other models we examined.

In this study I contrast hypotheses about the effects of family structure on premarital birth risks with three income hypotheses: (1) a low income hypothesis--that the risk of a premarital birth is higher for women from disadvantaged economic backgrounds because they possess fewer or less attractive economic opportunities; (2) a permanent income and transitory income hypothesis--that uncertainties generated by unexpected fluctuations in family income increase premarital birth risks net of absolute income levels; and (3) an income level and income change hypothesis--that downward trends in family income reflect worsening socioeconomic opportunities that increase premarital birth risks net of absolute income levels. I use prospective income and retrospective parental histories in the [U.S.] National Longitudinal Survey of Youth to determine if the effect of family instability...is an artifact of low unstable or declining income in the family of origin. (EXCERPT)

The authors examine three hypotheses regarding the impact of a womans family characteristics between birth and age 19 on her chances of having a premarital birth. "We construct dynamic measures of family structure using parent-history data from the [U.S.] National Survey of Families and Households. We use these data to examine the relative importance of family events during childhood changes in family structure during childhood and adolescence and durations spent in the modal family structures experienced by respondents while growing up. Our results suggest that these dynamic measures capture both theoretically and empirically distinct dimensions of family experience and that distinguishing between these dimensions provides sufficient analytical leverage to test the socialization social control and instability and change hypotheses." (EXCERPT)

We introduce a class of local hazard models that maintain parametric assumptions locally rather than globally. These models allow estimation of a flexible baseline hazard rate and nonproportional covariate effects. Recently developed local likelihood methods which generalize maximum likelihood methods can be used to estimate these models. We illustrate these techniques by estimating two local hazard models of first marriage--a local exponential model and a local Gompertz model--from data in the June 1980 [U.S.] Current Population Survey. We also compare results of the local hazard models with those of Coxs model an exponential model a piecewise exponential model and a piecewise Gompertz model. Estimates for the local exponential and local Gompertz models agree closely with nonparametric estimates for various subgroups. Moreover results of the local models provide interesting substantive insights into the process of first marriage that are not easily obtained from global models. (EXCERPT)

This chapter presents a smooth estimator of the hazard rate using a variable-span running loglinear specification that allows investigators to maintain only mild assumptions about the functional forms of population heterogeneity and time inhomogeneity in the rate. This estimator is useful both in exploratory data analyses (EDA) and in checking parametric assumptions. Examples drawn from data on the transition to first marriage for women in the U.S. show that several common parametric assumptions are violated in these data and illustrate that the smoothed hazard estimator can yield important insights not easily obtained from more conventional methods. (EXCERPT)

Roles and ways of thinking about roles have been a major concern of sociologists. One common approach to roles conceptualizes and analyzes them within networks of multiple social relations (see, for example, Radcliffe-Brown, 1940; Barnes, 1954; Nadel, 1957; Mayer, 1966; Kapferer, 1969; Mitchell, 1969; Bott, 1971; Boissevain, 1973; Laumann and Pappi, 1976). A recurrent theme throughout this literature is that the fundamental variables of interest are not particular characteristics of individuals but rather the social relations that connect