The Cost of Caring for Young Children

This study examines the "cost burden" of child care, defined as day care expenses divided by after-tax income. Data are from the wave 10 core and child care topical modules to the 1996 Survey of Income and Program Participation. We estimate that the average child under six years of age lives in a family that spends 4.9 percent of after-tax income on day care. However, this conceals wide variation: 63 percent of such children reside in families with no child care expenses and 10 percent are in families where the cost burden exceeds 16 percent. The burden is typically greater in single-parent than married-couple families but is not systematically related to a measure of socioeconomic status that we construct. One reason for this is that disadvantaged families use lower cost modes and pay less per hour for given types of care. The cost burden would be much less equal without low cost (presumably subsidized) formal care focused on needy families, as well as government tax and transfer policies that redistribute income towards them.

Welfare, the Earned Income Tax Credit, and the Labor Supply of Single Mothers

During 1984-96, welfare and tax policy changed dramatically. The Earned Income Tax Credit was expanded, welfare benefits were cut, welfare time limits were added and cases were terminated, Medicaid for the working poor was expanded, training programs were redirected, and subsidized or free child care was expanded. Many of the program changes were intended to encourage low income women to work. During this same time period there were unprecedented increases in the employment and hours of single mothers, particularly those with young children. In this paper, we first document these large changes in policies and employment. We then examine if the policy changes are the reason for the large increases in single mothers' labor supply. We find evidence that a large share of the increase in work by single mothers can be attributed to the EITC, with smaller shares for welfare benefit reductions, welfare waivers, changes in training programs, and child care expansions. We also find that most of these policies increased hours worked. Our results indicate that financial incentives through the tax and welfare systems have substantial effects on single mothers' labor supply decisions.

Three Essays on Labor Market Institutions and Low Income Populations: Dissertation Summary

The three essays that comprise this dissertation discuss three different sets of institutions affecting the lives of low-income populations. I start with a brief overview placing these essays into a larger body of research; then I present a fuller description of each individual essay. One of the difficulties in studying low-income groups is that their lives are touched by so many institutions. Moreover, these institutions often affect low-income groups differently than middle- or high-income groups. Perhaps nowhere is this more true than in the labor market. Increasing wage inequality since the early 1970s has reduced the return to work for the less skilled relative to those with more skill, in particular for males with less education. Over this same time period, males with less education also have experienced larger declines in employment. Less educated females, on the other hand, have not experienced analogous declines in wages and labor force participation, but both their wages and especially their labor force participation have increased much less rapidly than highly educated females

Entrepreneurship and Human Capital: Evidence of Patenting Activity from the Academic Sector.

This paper presents empirical evidence of the relationship between faculty entrepreneurial activity—quantified in terms of the propensity of U.S. university faculty to work directly with industry on research activities that lead to patents—and human capital, measured in terms of faculty tenure and age. Patenting reflects a unique dimension of faculty entrepreneurship, namely, collaborative activity that results in joint intellectual property. We find that faculty with tenure are more likely to engage in such activity, thus providing suggestive evidence of an externality associated with permanent employment. We also find that older faculty are more likely to engage with industry, to a point, holding tenure constant. Tenure and age proxy, respectively, what we call the “accumulated advantage” of faculty and their absorptive capacity. Because faculty patenting with industry involved both parties, our findings reflect that such faculty experience and expertise are important to industry to enter into a patenting relationship. Finally, we find that male faculty are more likely to patent with industry than female faculty

Entrepreneurship and human capital: Evidence of patenting activity from the academic sector. Entrepreneurship Theory and Practice

Abstract: This paper presents empirical evidence of the relationship between faculty entrepreneurial activity-quantified in terms of the propensity of U.S. university faculty to work directly with industry on research activities that lead to patents-and human capital, measured in terms of faculty tenure and age. Patenting reflects a unique dimension of faculty entrepreneurship, namely, collaborative activity that results in joint intellectual property. We find that faculty with tenure are more likely to engage in such activity, thus providing suggestive evidence of an externality associated with permanent employment. We also find that older faculty are more likely to engage with industry, to a point, holding tenure constant. Tenure and age proxy, respectively, what we call the "accumulated advantage" of faculty and their absorptive capacity. Because faculty patenting with industry involved both parties, our findings reflect that such faculty experience and expertise are important to industry to enter into a patenting relationship. Finally, we find that male faculty are more likely to patent with industry than female faculty. entrepreneurship | human capital | patenting | faculty entrepreneurial activity

Evolutionary life history theory as an organising framework for cohort studies : insights from the Cebu Longitudinal Health and Nutrition Survey

By tracking a group of individuals through time, cohort studies provide fundamental insights into the developmental time course and causes of health and disease. Evolutionary life history theory seeks to explain patterns of growth, development, reproduction and senescence, and inspires a range of hypotheses that are testable using the longitudinal data from cohort studies. Here we review two decades of life history theory-motivated work conducted in collaboration with the Cebu Longitudinal Health and Nutrition Survey (CLHNS), a birth cohort study that enrolled more than 3000 pregnant women in the Philippines in 1983 and has since followed these women, their offspring and grandoffspring. This work has provided evidence that reproduction carries “costs” to cellular maintenance functions, potentially speeding senescence, and revealed an unusual form of genetic plasticity in which the length of telomeres inherited across generations is influenced by reproductive timing in paternal ancestors. Men in Cebu experience hormonal and behavioural changes in conjunction with changes in relationship and fatherhood status that are consistent with predictions based upon other species that practice bi-parental care. The theoretical expectation that early life cues of mortality or environmental unpredictability will motivate a “fast” life history strategy are confirmed for behavioural components of reproductive decision making, but not for maturational tempo, while our work points to a broader capacity for early life developmental calibration of systems like immunity, reproductive biology and metabolism. Our CLHNS findings illustrate the power of life history theory as an integrative, lifecourse framework to guide longitudinal studies of human populations

Movements and Population Structure of Humpback Whales in the North Pacific

Despite the extensive use of photographic identification methods to investigate humpback whales in the North Pacific, few quantitative analyses have been conducted. We report on a comprehensive analysis of interchange in the North Pacific among three wintering regions (Mexico, Hawaii, and Japan) each with two to three subareas, and feeding areas that extended from southern California to the Aleutian Islands. Of the 6,413 identification photographs of humpback whales obtained by 16 independent research groups between 1990 and 1993 and examined for this study, 3,650 photographs were determined to be of suitable quality. A total of 1,241 matches was found by two independent matching teams, identifying 2,712 unique whales in the sample (seen one to five times). Site fidelity was greatest at feeding areas where there was a high rate of resightings in the same area in different years and a low rate of interchange among different areas. Migrations between winter regions and feeding areas did not follow a simple pattern, although highest match rates were found for whales that moved between Hawaii and southeastern Alaska, and between mainland and Baja Mexico and California. Interchange among subareas of the three primary wintering regions was extensive for Hawaii, variable (depending on subareas) for Mexico, and low for Japan and reflected the relative distances among subareas. Interchange among these primary wintering regions was rare. This study provides the first quantitative assessment of the migratory structure of humpback whales in the entire North Pacific basin