Discrete-time Event History Models Research Articles

The Effects of Financial Aid on College Success of Two-Year Beginning Nontraditional Students

This study aims to understand the role of financial aid in college success of two-year beginning nontraditional students. By applying discrete time event history models with propensity score covariate adjustment to a nationally representative sample from BPS: 04/09, this study answers research questions centering around the effects of Pell Grants, subsidized student loans and unsubsidized student loans on six-year college outcomes of nontraditional students (i.e. degree attainment, system departure, and continuous enrollment without a degree). The results of this study suggest that these nontraditional students were most likely to drop out in the third college year and that all three types of financial aid appeared effective for reducing dropout risks, but not for encouraging timely degree completion. These findings have significant implications for policy and practice including the necessity for considering the complexity of nontraditional student pathways, backgrounds and unique needs when designing and implementing financial aid policy. The findings also contribute to discussions on ways to fund nontraditional students and provide recommendations for institutions serving large populations of nontraditional students to promote persistence to graduation.

Premarital Births and Union Formation in Rural South Africa.

In rural South Africa, women often delay union formation until they are in their late 20s, though premarital first births are common. Longitudinal data from the Agincourt Health and Socio-Demographic Surveillance System in rural South Africa were used to examine the relationship between premarital birth and union entry among 55,158 nonmigrant women aged 10-35 who took part in at least one annual census from 1993 to 2012. Discrete-time event history models were used to determine whether the likelihood of union formation differed between women who had had a premarital first birth and those who had not. Associations between single motherhood and union type (marriages or nonmarital partnerships) were identified using logistic regression. Forty-five percent of women had had a premarital first birth and 25% had entered a first union. Women who had had a premarital first birth were less likely than other women to have entered a first union (odds ratio, 0.6). Women who had had a premarital birth in the past year were more likely than those without a premarital birth to have entered a union (1.5), but women had reduced odds of union formation if they had had a birth 1-2 years earlier (0.9) or at least five years earlier (0.8). Unions formed within two years of a premarital birth had an elevated likelihood of being nonmarital partnerships (1.2-1.4). Single motherhood is common in the Agincourt HDSS, and women with a premarital first birth face challenges in establishing committed unions with partners.

Amplification or suppression: Social networks and the climate change—migration association in rural Mexico

Increasing rates of climate migration may be of economic and national concern to sending and destination countries. It has been argued that social networks—the ties connecting an origin and destination—may operate as “migration corridors” with the potential to strongly facilitate climate change-related migration. This study investigates whether social networks at the household and community levels amplify or suppress the impact of climate change on international migration from rural Mexico. A novel set of 15 climate change indices was generated based on daily temperature and precipitation data for 214 weather stations across Mexico. Employing geostatistical interpolation techniques, the climate change values were linked to 68 rural municipalities for which sociodemographic data and detailed migration histories were available from the Mexican Migration Project. Multi-level discrete-time event-history models were used to investigate the effect of climate change on international migration between 1986 and 1999. At the household level, the effect of social networks was approximated by comparing the first to the last move, assuming that through the first move a household establishes internal social capital. At the community level, the impact of social capital was explored through interactions with a measure of the proportion of adults with migration experience. The results show that rather than amplifying, social capital may suppress the sensitivity of migration to climate triggers, suggesting that social networks could facilitate climate change adaptation in place.

Family formation and crime: What role for the family network?

Abstract Being part of a family involved with crime may shape one's own family formation process through constraints in the partner market and one's own family-related preferences. In this paper, we examine the role crime in family networks plays for two important family processes: the transition to parenthood and the transition to first marriage. Using high-quality, individual-level register data from Norway, we estimate discrete-time event history models of the transition to first marriage and parenthood. Results show that crime in the family network, for both men and women, is associated with lower transition rates to first marriage and higher transition rates to first birth. (104 words)

Trends in Determinants of Entry into the Academic Career: The Case of South Korea, 1980-2010.

Substantial research documents the determinants of entry into the academic career, yet little is known about how these determinants have evolved over time. Using data from a large sample of Korean scholars who received their doctoral degrees between 1980 and 2010, we estimate discrete-time event history models of transitioning to an academic position in any academic field. Results indicate that universalistic characteristics, such as publication record, strongly affect subsequent career success, but so do particularistic factors, including doctoral institution prestige. Since the 1980s, the influence of doctoral degree prestige increased substantially more than the influence of one’s publication record on higher education employment, implying that the rising importance of particularistic factors has outpaced growing consideration of universalistic characteristics in Korean academia. However, the importance of gender on academic employment has declined since the early 2000s, suggesting that the implementation of employment quotas for female professors may have stymied gender discrimination.

The Benefits of Educational Attainment for U.S. Adult Mortality: Are they Contingent on the Broader Environment?

The growing recognition that educational attainment is one of the strongest preventive factors for adult health and longevity has fueled an interest in educational attainment as a population health strategy. However, less attention has been given to identifying social, economic, and behavioral resources that may moderate the health and longevity benefits of education. We draw on theories of resource substitution and multiplication to examine the extent to which the education–mortality association is contingent on other resources (marriage, employment, income, healthy lifestyles). We use data on adults aged 30–84 in the 1997–2006 National Health Interview Survey Linked Mortality File and estimate discrete-time event history models stratified by gender (N = 146,558; deaths = 10,399). We find that the mortality benefits of education are generally largest for adults—especially women—who have other resources such as employment and marriage, supporting the theory of resource multiplication. Nonetheless, our results also imply that other resources can potentially attenuate the mortality disadvantages (advantages) associated with low (high) levels of education. The findings suggest that efforts to improve population health and longevity by raising education levels should be augmented with strategies that assure widespread access to social, economic, and behavioral resources.

The association between education and induced abortion for three cohorts of adults in Finland

This paper explores whether the likelihood of abortion by education changed over time in Finland, where comprehensive family planning services and sexuality education have been available since the early 1970s. This subject has not previously been studied longitudinally with comprehensive and reliable data. A unique longitudinal set of register data of more than 250,000 women aged 20–49 born in 1955–59, 1965–69, and 1975–79 was analysed, using descriptive statistics, concentration curves, and discrete-time event-history models. Women with basic education had a higher likelihood of abortion than others and the association grew stronger for later cohorts. Selection into education may explain this phenomenon: although it was fairly common to have only basic education in the 1955–59 cohort, it became increasingly unusual over time. Thus, even though family planning services were easily available, socio-economic differences in the likelihood of abortion remained.

In Sickness and in Health? Physical Illness as a Risk Factor for Marital Dissolution in Later Life.

The health consequences of marital dissolution are well known, but little work has examined the impact of health on the risk of marital dissolution. We use a sample of 2,701 marriages from the Health and Retirement Study to examine the role of serious physical illness onset in subsequent marital dissolution via either divorce or widowhood. We use a series of discrete time event history models with competing risks to estimate the impact of husband's and wife's physical illness onset on risk of divorce and widowhood. We find that only measures of wife's illness onset are associated with elevated risk of divorce, while measures of either spouse's illness onset is associated with elevated risk of widowhood. Further, in the case of heart problems, we find that this gender difference is statistically significant. These findings suggest health as a determinant of marital dissolution in later life via both biological and gendered social pathways.

Factors influencing fertility preference of a developing country during demographic transition: Evidence from Bangladesh

Fertility preferences indicate the extent of intended control over reproductive outcomes, and are therefore vital components in the analysis of individual fertility behavior and aggregate fertility trends of a country. Despite extensive research, dissimilarities remain regarding the prior stated fertility preferences and subsequent fertility behavior, especially in case of developing countries like Bangladesh; where third stage of demographic transition begun as a result of continuous assessment. The purpose of this paper is to analyze the differentials of fertility preference as well as the possible timing of the next parity progression of those Bangladeshi couples having positive intentions for more children. BDHS-2007 data is used to estimate a series of discrete time event history models of fertility preference and possible timing for next parity progression considering the dynamic nature of fertility preferences, and controlling for changing reproductive life cycle factors and socioeconomic background predictors of fertility. Findings suggest that though death of last child plays a vital role; there is a complex structure of the decision-making around fertility along with gender preference, abortions, couples educational level, mother’s participation in labor force. Although socio-economic classes don’t have significant influence on fertility preference, mother’s age plays vital role on fertility preference and desired waiting time in Bangladesh.South East Asia Journal of Public Health Vol.4(2) 2014: 23-30

In sickness and in health? Physical illness as a risk factor for marital dissolution in later life.

The health consequences of marital dissolution are well known, but little work has examined the impact of health on the risk of marital dissolution. In this study we use a sample of 2,701 marriages from the Health and Retirement Study (1992-2010) to examine the role of serious physical illness onset (i.e., cancer, heart problems, lung disease, and/or stroke) in subsequent marital dissolution due to either divorce or widowhood. We use a series of discrete-time event history models with competing risks to estimate the impact of husband's and wife's physical illness onset on risk of divorce and widowhood. We find that only wife's illness onset is associated with elevated risk of divorce, while either husband's or wife's illness onset is associated with elevated risk of widowhood. These findings suggest the importance of health as a determinant of marital dissolution in later life via both biological and gendered social pathways.

Better Off Alone Than With a Smoker: The Influence of Partner's Smoking Behavior in Later Life.

We examine how the likelihood of smoking cessation among smokers and patterns of adherence to smoking cessation differ by partnership status, partnership changes, and partners' smoking behavior. The data are a nationally representative sample of smokers in middle and older age from the Health and Retirement Study (1992-2010). We use multivariate logistic regression models to analyze the likelihood of smoking cessation among smokers and then estimate adherence to smoking cessation using discrete-time event history models. Those partnered with smokers and those whose partners relapse into smoking are much less likely than the unpartnered to quit smoking and adhere to smoking cessation. Respondents partnered with non-smokers and those whose partners quit smoking are more likely to quit smoking than the unpartnered. Those recently widowed, divorced, and repartnered have similar smoking changes to the consistently unpartnered. Being partnered does not always mean healthier behavior changes. Rather, the association between partnership status and smoking changes depends greatly on the health behavior changes of the partner. The partnership context at the time of smoking cessation sets the stage for longer term patterns of adherence, shaping health in older age.

Social Relationships, Gender, and Recovery From Mobility Limitation Among Older Americans.

Evidence suggests social relationships may be important facilitators for recovery from functional impairment, but the extant literature is limited in its measurement of social relationships including an over emphasis on filial social support and a paucity of nationally representative data. Using data from Waves 4-9 (1998-2008) of the Health and Retirement Study (HRS), this research examines the association between social relationships and recovery from severe mobility limitation (i.e., difficulty walking one block or across the room) among older Americans. Using a more nuanced measure of recovery that includes complete and partial recovery, a series of discrete-time event history models with multiple competing recovery outcomes were estimated using multinomial logistic regression. Providing instrumental support to peers increased the odds of complete and partial recovery from severe mobility limitation, net of numerous social, and health factors. Having relatives living nearby decreased the odds of complete recovery, while being engaged in one's neighborhood increased the odds of partial recovery. The influence of partner status on partial and complete recovery varied by gender, whereby partnered men were more likely to experience recovery relative to partnered women. The effect of neighborhood engagement on partial recovery also varied by gender. Disengaged women were the least likely to experience partial recovery compared with any other group. The rehabilitative potential of social relationships has important policy implications. Interventions aimed at encouraging older adults with mobility limitation to be engaged in their neighborhoods and/or provide instrumental support to peers may improve functional health outcomes.

Social Supports as Enabling Factors in Nursing Home Admissions: Rural, Suburban, and Urban Differences.

This study investigates differences in social support and nursing home admission by rurality of residence. We use discrete-time event history models with longitudinal data from seven waves (1998-2010) of the Health and Retirement Study to prospectively examine the risk of spending 30 or more days in a nursing home (n = 5,913). Results show that elders with a health problem who live in rural areas of the South or Midwest have approximately 2 times higher odds of nursing home entry than elders living in urban areas in the Northeast. Rural elders report somewhat higher social support than non-rural elders, and controlling for these forms of social support does not explain the higher risk of a nursing home stay for Southerners and Midwesterners living in rural areas. Results suggest that social support has a similar association with nursing home entry for rural, suburban, and urban elders.

Unravelling the temporal association between lameness and body condition score in dairy cattle using a multistate modelling approach

Recent studies have reported associations between lameness and body condition score (BCS) in dairy cattle, however the impact of change in the dynamics of BCS on both lameness occurrence and recovery is currently unknown. The aim of this longitudinal study was to investigate the effect of change in BCS on the transitions from the non-lame to lame, and lame to non-lame states. A total of 731 cows with 6889 observations from 4 UK herds were included in the study. Mobility score (MS) and body condition score (BCS) were recorded every 13–15 days from July 2010 until December 2011. A multilevel multistate discrete time event history model was built to investigate the transition of lameness over time. There were 1042 non-lame episodes and 593 lame episodes of which 50% (519/1042) of the non-lame episodes transitioned to the lame state and 81% (483/593) of the lame episodes ended with a transition to the non-lame state. Cows with a lower BCS at calving (BCS Group 1 (1.00–1.75) and Group 2 (2.00–2.25)) had a higher probability of transition from non-lame to lame and a lower probability of transition from lame to non-lame compared to cows with BCS 2.50–2.75, i.e. they were more likely to become lame and if lame, they were less likely to recover. Similarly, cows who suffered a greater decrease in BCS (compared to their BCS at calving) had a higher probability of becoming lame and a lower probability of recovering in the next 15 days. An increase in BCS from calving was associated with the converse effect, i.e. a lower probability of cows moving from the non-lame to the lame state and higher probability of transition from lame to non-lame. Days in lactation, quarters of calving and parity were associated with both lame and non-lame transitions and there was evidence of heterogeneity among cows in lameness occurrence and recovery. This study suggests loss of BCS and increase of BCS could influence the risk of becoming lame and the chance of recovery from lameness. Regular monitoring and maintenance of BCS on farms could be a key tool for reducing lameness. Further work is urgently needed in this area to allow a better understanding of the underlying mechanisms behind these relationships.

Female Migration and Native Marital Stability: Insights from Italy

In this paper, we argue that the size and the composition of the female migrant population in a given area can affect the marital stability of natives. We take Italy as a case-study and we offer discrete-time event history models predicting marital disruption on data from the nationally – representative 2009 Family and Social Subjects survey. We found that the increasing presence of first mover migrant women (coming from Latin America and Eastern Europe) is associated with higher separation risks among natives, especially for couples with lower human capital. Our findings add to our understanding of family formation and dissolution dynamics in recent immigration countries.

Marrying Ain’t Hard When You Got A Union Card? Labor Union Membership and First Marriage

Over the past five decades, marriage has changed dramatically, as young people began marrying later or never getting married at all. Scholars have shown how this decline is less a result of changing cultural definitions of marriage, and more a result of men’s changing access to social and economic prerequisites for marriage. Specifically, men’s current economic standing and men’s future economic security have been shown to affect their marriageability. Traditionally, labor unions provided economic standing and security to male workers. Yet during the same period that marriage has declined among young people, membership in labor unions has declined precipitously, particularly for men. In this article, we examine the relationship between union membership and first marriage and discuss the possible mechanisms by which union membership might lead to first marriage. We draw on longitudinal data from the National Longitudinal Survey of Youth-79 to estimate discrete time event-history models of first marriage entry and find that, controlling for many factors, union membership is positively and significantly associated with marriage. We show then that this relationship is largely explained by the increased income, regularity and stability of employment, and fringe benefits that come with union membership.

Varying association between education and second births in Europe

Background: Previous research has shown considerable variation in the relationship between women’s educational attainment and second births in contemporary Europe. A negative association is found in some countries, while a positive or non-negative relationship is reported in others. Existing studies come mainly from single-country perspectives, which renders the results not strictly comparable. Objective: We investigate the association between women’s and their partners’ educational attainment and transition to second births comparatively in regions and sub-regions of Europe. Methods: The data come from the 2005 and 2011 waves of the EU Statistics on Income and Living Conditions (EU-SILC). We estimate separate discrete-time event history models for regions and sub-regions and multilevel models for all EU-SILC countries. Results: Northern Europe exhibits a positive association between women’s and their partners’ education and second childbearing. Western Europe features a positive relationship among partners but demonstrates a U-shaped pattern among women. This pattern occurs due to German-speaking countries where women’s educational attainment appears inversely related to second births. A negative relationship between women’s education and second childbearing also prevails in Eastern Europe; in some sub-regions it extends to male partners. Except for in Eastern Europe, the time-squeeze adds to the positive effect of women’s high education. In Northern Europe it enables highly educated women to wholly catch up with their counterparts with medium and low education as regards the proportion having second births. In Southern Europe, by contrast, the educational gradient turns negative following the consideration of the time-squeeze effect. Conclusions: We conclude that the relationship between educational attainment and second births varies not only by individual country but also by larger geographical area in Europe. Although smaller in scale than among women, the variation also extends to male partners.

Earnings Equality and Relationship Stability for Same-Sex and Heterosexual Couples.

This paper examines a topic of continuing interest for demographers and sociologists of the family: which factors promote relationship stability among couples. Two competing theories have been highly debated to explain how relative earnings relate to relationship quality and stability. The neoclassical economic theory posits that specialization of home and work duties leads to stability because partners fill complementary roles. Gender scholars propose an alternative explanation, suggesting that when couples violate the traditional male breadwinner model, they experience relationship strain and are more likely to experience a breakup. Using the new How Couples Meet and Stay Together (HCMST) dataset, this paper offers a unique perspective on the debate, by comparing same-sex couples to heterosexual couples. The paper presents three sets of analyses to determine how relative earnings relate to relationship stability. The first analysis employs discrete-time event history models to assess the likelihood of breakup for both heterosexual and same-sex cohabiting couples. Next, the paper presents results predicting self-reported relationship quality among married and cohabiting couples. The final analysis focuses on non-cohabiting couples from Wave I of the HCMST survey and examines the likelihood of entering cohabitation in subsequent survey waves. Results demonstrate that the economic or specialization model does not hold in same-sex relationships, suggesting that the effect of earnings equality is dependent upon gender norms in heterosexual relationships. When earnings power is disentangled from gender, as is the case of same-sex couples, equality in earnings promotes stability.

Does Fertility Behavior Spread among Friends?

By integrating insights from economic and sociological theories, this article investigates whether and through which mechanisms friends’ fertility behavior affects an individual’s transition to parenthood. By exploiting the survey design of the Add Health data, our strategy allows us to properly identify interaction effects and distinguish them from selection and contextual effects. We use a series of discrete-time event history models with random effects at the dyadic level. Results show that, net of confounding effects, a friend’s childbearing increases an individual’s risk of becoming a parent. We find a short-term, curvilinear effect: an individual’s risk of childbearing starts increasing after a friend’s childbearing, reaches its peak approximately two years later, and then decreases.

Social and Economic Determinants of Reproductive Behavior Before the Fertility Decline. The Case of Six Italian Communities During the Nineteenth Century

In recent decades, main demographic historical research assessed the importance of bio-demographic components in human reproduction, before the diffusion of birth control and contraceptive techniques. According to this dominant view, before fertility decline, marital fertility was mainly regulated by biological and physiological factors and socio-economic factors played only a limited and indirect role. In order to demonstrate the importance of non-biological components, the present study focuses on six pre-transitional communities situated in different geographic areas of Italy. The work aims to demonstrate how fertility levels could significantly be affected by social and economic factors even in natural fertility populations, before the diffusion of contraceptives. Micro-level data are collected from several historical sources, and discrete-time event history models are applied to female reproductive careers in order to estimate effects of socio-economic status, household structure, and price fluctuations on marital fertility, controlling for several bio-demographic factors. Despite clear differences in geographic localization and environment, marital reproductive behavior appeared to be significantly and constantly affected by socio-economic status, household composition, and price levels in all the investigated communities.