386 research outputs found
Do Children from Welfare Families Obtain Less Education?
This study estimates the relationship between parental welfare receipt and children’s adulthood educational attainment. Data come from the Panel Study of Income Dynamics. Cross-sectional regression results confirm findings from previous studies that greater parental welfare receipt is significantly associated with children’s poorer educational attainment. Fixed-effect regressions indicate that the relationship between parental welfare receipt and children’s educational outcomes becomes weaker after controlling for unobserved family characteristics, but they do not eliminate the negative relationship. The relationship between parental welfare receipt and children’s educational attainment is not uniform across childhood stages. Additional analyses suggest that parental welfare receipt is not negatively related to educational attainment if combined with at least quarter-time work by the mother.
Instrument selection: The case of teenage childbearing and women's educational attainment
Recent research has identified situations in which instrumental variables (IV) estimators are severely biased and has suggested diagnostic tests to identify such situations. We suggest a number of alternative techniques for choosing a set of instruments that satisfy these tests from a universe of a priori plausible candidates, and we apply them to a study of the effects of adolescent childbearing on the educational attainment of young women. We find that substantive results are sensitive to instrument choice, and make two recommendations to the practical researcher: First, it is prudent to begin with a large set of potential instruments, when possible, and pare it down through formal testing rather than to rely on a minimal instrument set justified on a priori grounds. Second, the application of more restrictive tests of instrument validity and relevance can yield results very different from those based on less restrictive tests that produce a more inclusive set of instruments, and is the preferred, conservative approach when improper instrument choice can lead to biased estimates.
How Does Adolescent Fertility Affect the Human Capital and Wages of Young Women?
The consequences of teen childbearing for the future well-being of young women remain controversial. In this paper, we model and estimate the relationship between early childbearing and human capital investment, and its effect on wages in early adulthood. Taking advantage of a large set of potential instruments for fertility—principally state- and county-level indicators of the costs of fertility and fertility control—we use instrumental variables procedures to generate unbiased estimates of the effects of early fertility on education and work experience, and the effects of these outcomes on adult wages. For both black and white women, adolescent fertility substantially reduces years of formal education and teenage work experience. White teenage mothers also obtain less early adult work experience than young women who delay childbearing. We also find that, through these human capital effects, teenage childbearing has a significant effect on a young woman’s market wage at age 25. Our results, unlike those of recent “revisionist” studies, suggest that public policies that reduce teenage childbearing are likely to have positive effects on the economic well-being of many young mothers and their families.
Do Attitudes and Personality Characteristics Affect Socioeconomic Outcomes? The Case of Welfare Use by Young Women
We develop and estimate a model of social-psychological determinants of entry to the Aid to Families with Dependent Children (AFDC) program, the primary cash welfare program in the United States for 60 years until replaced in 1996. The structural model holds that attitudes and personality characteristics influence a woman’s likelihood of becoming demographically and financially eligible for welfare and her willingness to bear the stigma of receiving benefits. These factors, in turn, affect the likelihood of actually going on welfare. We test for a relationship between social-psychological variables and welfare participation using data from the youngest cohorts of women in the National Longitudinal Survey of Youth. We estimate logit models of the probability of ever participating in AFDC up to age 25 and hazard models of the timing until first use of AFDC. The attitudes and personality characteristics in the empirical model are self-esteem, locus of control, attitudes toward school, attitudes toward women’s work and family roles, commitment to work, and aversion to accepting public assistance. We find strong associations between welfare use and several attitudes and personality characteristics, but most of the associations are not robust to the inclusion of exogenous personal and family background characteristics. Consistent, strong evidence suggests that more positive attitudes toward school lower the likelihood of using welfare and increase duration until first receipt.
The Twentieth Century Record of Inequality and Poverty in the United States
When the twentieth century is viewed as a whole, no clear trend in income inequality emerges. Inequality was high and rising during the first three decades and peaked during the Depression. It fell sharply during World War II and remained at the lower level in the 1950s and 1960s. From the 1970s through the mid-1990s inequality steadily increased to levels not seen since World War II, though well below those during the first three decades. The rate of poverty exhibited a long-run downward trend from about 60–70 percent in the earlier years of the century to the 12–14 percent range in recent years, with considerable fluctuation around this secular trend. Changes in inequality were produced largely by demographic and technological changes, the growth and decline of various industries, changes in patterns of international trade, cyclical unemployment, and World War II. The primary drivers of the rate of poverty were economic growth and factors that produced changes in income inequality, particularly demographic change and unemployment. Public policy has reduced the market-generated level of inequality, but since 1950 has had little effect on the trend in inequality. Prior to 1950, the growth of government, and particularly the introduction of a broadly based income tax during World War II, coincided with and partly produced the sharp downward shift in inequality of that era. Government had little effect on poverty rates until 1950. Public income transfer programs have reduced poverty rates appreciably in recent decades. Since World War II, when they have been on a large enough scale to matter, changes in tax and transfer policy have tended to reinforce market-generated trends in inequality and poverty rather than offset them.
Jurassic Pork: What Could a Jewish Time Traveler Eat?
Paleontologists use multiple methods to reconstruct the anatomy and behavior of extinct animals, including direct observations from well-preserved fossils and inferences from the phylogeny of modern and extinct relatives. We illustrate these techniques by reference to the biblical definitions of kosher and non-kosher animals; that is, how can we apply these approaches to the hypothetical question of whether an extinct form would have been kosher. The biblical categories do not readily map to modern understandings of systematics, but are heavily based on life mode. When given, distinguishing characteristics, such as the presence of fins and scales in aquatic animals, can be readily seen directly in fossils. In other cases, such as cud chewing, they need to be inferred from the phylogenetic relationships of the fossil forms. Dinosaurs (other than birds), unfortunately, are not kosher. A kosher “paleo diet” would be increasingly difficult further in the past. The use of biblical content as a way of introducing concepts from paleontology and evolutionary biology, such as crown groups and stem groups, should be of broad interest.https://doi.org/10.1186/s12052-015-0047-
Universal Formulae for Percolation Thresholds
A power law is postulated for both site and bond percolation thresholds. The
formula writes , where is the space
dimension and the coordination number. All thresholds up to are found to belong to only three universality classes. For first two
classes for site dilution while for bond dilution. The last one
associated to high dimensions is characterized by for both sites and
bonds. Classes are defined by a set of value for . Deviations
from available numerical estimates at are within and
for high dimensional hypercubic expansions at . The
formula is found to be also valid for Ising critical temperatures.Comment: 11 pages, latex, 3 figures not include
Lacunarity of the Spatial Distributions of Soil Types in Europe.
Lacunarity as a means of quantifying textural properties of spatial distributions suggests a classification into three main classes of the most abundant soils that cover 92% of Europe. Soils with a well-defined self-similar structure of the linear class are related to widespread spatial patterns that are nondominant but ubiquitous at continental scale.
Fractal techniques have been increasingly and successfully applied to identify and describe spatial patterns in natural sciences. However, objects with the same fractal dimension can show very different optical properties because of their spatial arrangement. This work focuses primary attention on the geometrical structure of the geographical patterns of soils in Europe. We made use of the European Soil Database to estimate lacunarity indexes of the most abundant soils that cover 92% of the surface of Europe and investigated textural properties of their spatial distribution. We observed three main classes corresponding to three different patterns that displayed the graphs of lacunarity functions, that is, linear, convex, and mixed. They correspond respectively to homogeneous or self-similar, heterogeneous or clustered and those in which behavior can change at different ranges of scales. Finally, we discuss the pedological implications of that classification
Participatory Design for the Social Media Needs of Emergency Public Information Officers
ABSTRACT This paper describes the design, execution, and results of a participatory design workshop with emergency public information officers (PIOs). During the workshop, PIOs and researchers explored ideas and designs for supporting the social media needs of PIO work. Results indicate that PIO perceptions of social media have changed as they have learned to incorporate activities of the public into their work, yet they still struggle with issues of trust and liability. Based on workshop design activities, the paper offers a set of design recommendations for supporting the social media needs of PIO work practice such as the ability to monitor, document, and report social media activity
Long-Term Maintenance of Treatment Outcomes: Diabetes Personal Trainer Intervention for Youth With Type 1 Diabetes
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