Search

BACKGROUND In the U.S. today, premarital first births occur disproportionately to women with low education and income. We lack studies of whether this education gradient was present in cohorts born earlier. OBJECTIVE We examine education differences in the proportion of U.S. white and black women who: (a) experienced a premarital conception taken to term resulting in a first birth, and (b) had a premarital first birth by age 35. Among those experiencing a premarital conception, we examine the association between education and whether women married before the birth. We examine these patterns for birth cohorts born between 1925 and 1959. METHODS We use the 1980, 1985, 1990, and 1995 June Fertility Supplements from the U.S. Current Population Survey to examine cohorts of women born between 1925 and 1959. The survey asked women the dates of their first marriage and their first birth, allowing us to determine premarital conceptions taken to term, and whether the resulting first births occurred within or outside of first marriage. We present descriptive information on the proportion of black and white women in each cohort who experienced the events of interest by age 35. RESULTS For all cohorts, women with low education were generally more likely than their more educated counterparts to experience premarital conceptions and premarital first births. For blacks, but not whites, who experienced a premarital conception that was taken to term, those with more education were more likely to marry before the birth. CONCLUSIONS In the U.S., the concentration of premarital conceptions and premarital first births among less educated women was present for cohorts extending back to those born in 1925. 1. Introduction It is well known that, in the U.S., nonmarital births have increased for both whites and blacks (Bachu 1999; Wu 2008; Ventura 2009), and that, in recent decades, women who have nonmarital births are disproportionately of low education and income (Upchurch et al. 2002; Ellwood and Jencks 2004). This paper examines whether the relationship between education and having a premarital conception or first birth existed for earlier U.S. birth cohorts. 2. Data and methods We pool data from the retrospective marital and fertility histories from the June 1980, 1985, 1990, and 1995 U.S. Current Population Surveys (CPS). These June CPS fertility and marital supplements were administered to married women aged 15 or older and never-married women aged 18 or older. We use these data to identify the date (to the nearest month) of first births and first marriages. We assume that all conceptions occurred nine months prior to the birth, and employ a definition of a premaritally conceived but postmarital first birth as a first birth occurring less than seven months after a first marriage.4 This in effect assumes that first births that occur seven or eight months after a first marriage are premature births conceived within marriage. This procedure clearly introduces some classification errors, but provides a standard operational definition of a premarital conception for those conceptions taken to term. Because these data contain no information on pregnancies ending in miscarriage or abortion, our analyses are limited to conceptions taken to term. A further limitation of these data is that they lack information on cohabitation. However, the vast majority of premarital conceptions taken to term and resulting in a first birth to women born between 1925 and 1959 occurred in periods when abortion and cohabitation were relatively uncommon. Unweighted estimates are presented throughout. We limit our analysis to first marriages and first births. For the birth cohorts we examine, about three out of four premarital conceptions taken to term involved first births, and about nine out of ten marriages occurring between a premarital conception and a first birth were first marriages (results not shown). …

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.

Historical trends in U.S. nonmarital fertility have been compiled almost exclusively from vital statistics on births. This paper complements this historical record by providing cohort estimates of nonmarital fertility for cohorts of U.S. women spanning approximately 50 years of cohort experience. Life table estimates using retrospective marital and fertility histories in the June 1980, 1985, 1990, and 1995 Current Population Surveys reveal nonnegligible levels of nonmarital fertility historically. For women born between 1925 and 1929, nearly 1 in 10 had at least one nonmarital birth by age 30. For women born between 1965 and 1969, more than 1 of 4 had one or more nonmarital births by age 30, with roughly 1 of 5 white, 3 of 5 black, and 1 in 3 Hispanic women having at least one nonmarital birth by age 30. Life table estimates reveal a twofold increase between ages 20 and 30 in the percentage of women with at least one child outside of formal marriage for all cohorts of white and Hispanic women, and an increase of roughly two-thirds for all cohorts of black women. I also document qualitative differences in nonmarital fertility by race/ethnicity, with the percentage of nonmarital births following a divorce or marital separation for white women approximately twice that for black or Hispanic women. Finally, I introduce a new measure, the cohort nonmarital fertility ratio (CNMFR), which provides a cohort complement to the standard period nonmarital fertility ratio. Conservative estimates reveal a roughly threefold increase in the CNMFR for women born from 1925-1929 to 1950-1954 for both whites and blacks, despite substantially higher levels of nonmarital fertility among black women. Overall, these findings reveal surprisingly high levels of nonmarital fertility for women born since the 1920s and confirm that nonmarital fertility has become an increasingly substantial component of overall U.S. fertility

VOLUME 1 Overviews Event History Models for Life Course Analysis - Lawrence Wu Nonparametric Estimation: Theory Nonparametric Estimation from Incomplete Observations - E.L. Kaplan and Paul Meier Theory and Applications of Hazard Plotting for Censored Failure Data - Wayne Nelson Nonparametric Inference for a Family of Counting Processes - Odd Aalen A Flaw in Actuarial Exposed-to-Risk Theory - Jan Hoem Issues in Smoothing Empirical Hazards - Lawrence Wu Nonparametric Estimation: Applications The Incidence of Divorce within Cohorts of American Marriages Contracted since the Civil War - Samuel Preston and John McDonald Slipping Into and Out of Poverty: The Dynamics of Spells - Mary Jo Bane and David Ellwood Trends in Cohabitation and Implications for Children's Family Contexts - Larry Bumpass and Hsien-Hen Lu Cohort Estimates of Nonmarital Fertility - Lawrence Wu The Cox Model: Theory Regression Models and Life Tables - D. R. Cox Understanding Cox's Regression Model: A Martingale Approach - Richard Gill The Cox Model: Applications Unemployment over the Life Cycle: Racial Differences and the Effect of Changing Economic Conditions - Thomas DiPrete Entry into Marriage and Parenthood by Young Men and Women: The Influence of Family Background - Robert Michael and Nancy Brandon Tuma Parametric Models: Theory On the Nature of the Function Expressive of the Law of Human Mortality - Benjamin Gompertz The Distribution by Age of the Frequency of First Marriage - Ansley Coale and Donald McNeil The Process of Entry into First Marriage - Gudmund Hernes A Comparison of the 'Sickle Function' with Alternative Stochastic Models of Divorce Rates - Andreas Diekmann and Peter Mitter VOLUME 2 Parametric Models: Applications The Divergence of Black and White Marriage Patterns - Neil Bennett, David Bloom and Patricia Craig Social Inheritance of Divorce in Postwar Germany - Andreas Diekman and Henriette Engelhardt Legal Environments and Organizational Governance: The Expansion of Due Process in the American Workplace - Lauren Edelman Contextual Effects in the Classroom: The Impact of Ability Groups on Student Attention - Diane Felmlee and Donna Eder The Liability of Newness: Age Dependence in Organizational Death Rates - John Freeman, Glenn Carroll and Michael Hannan Income and Independence Effects on Marital Dissolution: Results from the Seattle and Denver Income-Maintenance Experiments - Michael Hannan, Nancy Brandon Tuma and Lyle Groeneveld Diverging Fertility Among U.S. Women Who Delay Childbearing - Steven Martin Rewards, Resources and the Rate of Mobility: A Nonstationary Multivariate Stochastic Model - Nancy Brandon Tuma Work as a Turning Point in the Life Course of Criminals: A Duration Model of Age, Employment, and Recidivism - Christopher Uggen Time-Varying Covariates: Applications Social Change, the Social Organization of Families and Fertility Limitation - William Axinn and Scott Yabiku Principles of Cohesion in Cohabitation and Marriage - Julie Brines and Kara Joyner An Event History Analysis of Racial Rioting in the 1960s - Daniel Myers Questions in Time: Investigating the Structure and Dynamics of Unfolding Classroom Discourse - Martin Nystrand, Lawrence Wu, Adam Gamoran, Susie Zeiser and Daniel Long Family Structure and the Risk of a Premarital Birth - Lawrence Wu and Brian Martinson Effects of Family Instability, Income and Income Instability on the Risk of a Premarital Birth - Lawrence Wu VOLUME 3 Discrete-Time Models: Theory Discrete-Time Methods for the Analysis of Event Histories - Paul Allison Change and Stability in Educational Stratification - Robert Mare Discrete-Time Models: Applications Mothers, Children, and Cohabitation: The Intergenerational Effects of Attitudes and Behavior - William Axinn and Arland Thornton Two Decades of Family Change: The Shifting Economic Foundations of Marriage - Megan Sweeney No Trend in the Intergenerational Transmission of Divorce - Jui-Chung Allen Li and Lawrence Wu Another Look at the Stratification of Educational Transitions: The Logistic Response Model with Partial Proportionality Constraints - Robert Hauser and Megan Andrew Unobserved Heterogeneity: Theory Heterogeneity's Ruses: Some Surprising Effects of Selection on Population Dynamics - James Vaupel and Anatoli Yashin A Method for Minimizing the Impact of Distributional Assumptions in Econometric Models for Duration Data - James Heckman and Burton Singer Heterogeneity, Omitted Variable Bias and Duration Dependence - Gary Chamberlain Simultaneous Equations for Hazards: Marriage Duration and Fertility Timing - Lee Lillard Kindred Lifetimes: Frailty Models in Population Genetics - J.W. Vaupel Unobserved Heterogeneity: Applications Interrelated Family-Building Behaviors: Cohabitation, Marriage, and Nonmarital Conception - Michael Brien, Lee Lillard and Linda Waite Does Unemployment Cause Future Unemployment? Definitions, Questions, and Answers from a Continuous Time Model of Heterogeneity and State Dependence - James Heckman and George Borjas New Evidence on the Timing and Spacing of Births - James Heckman, V. Joseph Hotz and James Walker VOLUME 4 Competing Risks: Theory A Nonidentifiability Aspect of the Problem of Competing Risks - A Tsiatis The Identifiability of the Competing Risks Model - James Heckman and Bo Honore Competing Risks: Applications Drug Use and Other Determinants of Premarital Pregnancy and Its Outcome: A Dynamic Analysis of Competing Events - Kazuo Yamaguchi and Denise Kandel Social Capital and International Migration: A Test Using Information on Family Networks - Alberto Palloni, Douglas Massey, Miguel Ceballos, Kristin Espinosa and Michael Spittel Nonproportionalmodels Local Hazard Models - Lawrence Wu and Nancy Brandon Tuma Log-Multiplicative Models for Discrete-Time Discrete-Covariate Event History Data - Yu Xie An Approach to Nonparametric Regression for Life History Data using Local Linear Fitting - Gang Li and Hani Doss Trajectories of Fetal Loss in the Czech Republic - Elwood Carlson, Jan Hoem and Jitka Rychtarikova Left Truncation and Left Censoring On the Treatment of Interrupted Spells and Initial Conditions in Event History Analysis - Alfred Hamerle The Distribution of Single Spell Duration Data - Geert Ridder Models for Clustered, Sequential, and Diffusion Processes Estimating a Multivariate Proportional Hazards Model for Clustered Data Using the EM Algorithm, with an Application to Child Survival in Guatemala - Guang Guo and German Rodriguez Multivariate Survivorship Analysis Using Two Cross-Sectional Samples - Mark Hill A Nested Frailty Model for Survival Data, With an Application to the Study of Child Survival in Northeast Brazil - Narayan Sastry Spatial and Temporal Heterogeneity in Diffusion - David Strang and Nancy Brandon Tuma Effects of Exposure on Prevalence and Cumulative Risk: Direct and Indirect Effects in a Recursive Hazard Model - Lawrence Wu and Steven Martin

Most studies that examine the effects of family structure have employed relatively crude measures, typically a snapshot of family intactness at age 14. In this article, we use data from the National Survey of Families and Households to examine (a) how one might better construct measures of family structure that reflect change during early life and (b) what analytical and empirical opportunities are available when the data provide a more complete parent history. We draw four conclusions. First, a substantial fraction of children have extremely diverse parental situations, even though the majority of children live in intact families. Snapshot measures understate greatly the dynamic complexities of a respondent's parental situation. Second, the parent histories of respondents provide a rich but complicated set of longitudinal data and the complexity of these data makes it infeasible to adopt a data-driven approach to summarize family structure over the early lives of children. It is therefore useful to adopt a more theoretical approach in identifying salient dimensions of a respondent's parent history. Third, existing theoretical perspectives conceptualize the influences of parents in markedly different ways. These contrasting views, in turn, imply quite distinct empirical measures. Finally, more informative measures of family structure may allow one to adjudicate between alternative hypotheses of family structure in ways not possible with snapshot measures.

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.

Ermisch (2009) criticized Gray, Stockard, and Stone (2006), arguing that they incorrectly tested a model positing a nonlinear relationship between the nonmarital fertility ratio and the proportion of unmarried women. I identify a different problem, which is that even if this model were to hold for a particular population, it would not in general hold for subgroups of this population; likewise, were it to hold for subgroups, it would not hold for aggregations of these subgroups.

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)