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991.
We present findings from a nonexperimental evaluation of an employment program in which both partners in young, low-income,
primarily African-American couples simultaneously participated. Mothers participating in the couples program had larger immediate
gains in employment and earnings and decreases in TANF receipt following their exit from the program relative to mothers who
received employment assistance as individuals. Fathers showed similar although weaker results. These immediate benefits appeared
to be driven by higher rates of program completion among couples’ participants. Couples in which both partners completed the
program experienced the largest quarterly earnings gains, and couples with greater earnings’ gains were more likely to still
be together one year after the program ended. Mothers’ earnings gains eroded in the two years following program completion
and many reported new pregnancies and problems with child care. We suggest directions for future programs and encourage future
studies to consider the range of mechanisms associated with a couples focus, including potential motivational benefits and
unintended consequences.
相似文献
Carolyn J. Heinrich (Corresponding author)Email: |
992.
Infants often protest the activities of their caregivers, and this particular social interaction may provide an important window on early communication and its development. This study used naturalistic methods to investigate the development of vocal protests. Fifteen mother‐infant dyads at each of 5 ages, from 3 to 18 months, were observed at home. Maternal behaviors of caregiving and prohibiting were tallied from videotapes, as were infants' protests of these behaviors. Maternal caregiving decreased with age, but maternal prohibitions increased. There were no changes over age in the probability of protesting maternal caregiving behavior; however, 12‐month‐olds were more likely to protest prohibitions than 6‐ or 8‐month‐olds. Older infants were also more likely to use intense protests, such as screams, than younger infants. These age‐related changes were mirrored by the differences in prohibitions and protests observed between 8‐month‐olds who could crawl and those who could not. Findings from this study were related to previous research on infant crying as an important part of the prelinguistic communication system. 相似文献
993.
Edgar G. Karapetyan Anna A. Atoyan Marta E. Sandoyan Demeh Daradkah 《Transition Studies Review》2009,16(2):287-298
During the modern phase of economic reforms directed at the establishment of market economy, many countries with transition
economies face the challenge of solving the issue of formation and rational usage of internal sources of financing the real
sector of the economy, as well as attracting considerable volume of direct foreign investment. In general, financial market
imperfections hold back innovation and growth, and that public policy can complement financial markets. Therefore, the most
relevant issue at the present time is the formation of attendant and complex supervision institutions, as well as an exigency
of innovative economy governance as mainframe principles for further banking system elaboration and financial sector development
in general. We have taken Armenia as a case study for transition economy as far as Armenia is currently in the stage of capital
market development through integration into international financial markets.
相似文献
994.
Lee A. Smithey 《Sociology Compass》2009,3(4):658-671
Tactical choices and their execution are closely related to the construction of collective identities in social movements. Studying collective identity has helped scholars understand why people participate in collective action, but the array of tactics that constitute action has not been fully explored. An emerging interest in culture and strategy that situates social movement actors in a field of contention with opponents, allies, and bystanding publics raises questions about the tactics that are used and the construction of collective identity, which is formed in interaction with others. Strategies and tactics reflect collective identities but also provide opportunities for reaffirming or challenging them. Innovative methods can create tension as activists work to resolve what they do with who they feel they are. Conflict studies, nonviolent action studies, and sociological research using concepts such as framing, discourse, protest events, and tactical repertoires offer tools with which to bridge tactics and collective identity. 相似文献
995.
As STD infections including HIV increase in the United States, it has become increasingly important to policy makers to ascertain the extent to which knowledge and perceptions of AIDS risk affect an individual's probability of altering their sexual or contraceptive behavior to avoid infection. This paper examines the extent to which women's perceptions of their own and their partners' risk of HIV infection affects the probability of using a condom for protection against sexually transmitted diseases. This paper also examines the extent to which HIV testing may affect motivation for condom use. Crosstabulations reveal that prophylactic condom use is more prevalent among women who have been tested for HIV and increase as perceptions of their chance (and their partner's chance) of being positive increases. The multivariate results from this study indicate that having an HIV test significantly predicts the likelihood of using a condom for STD prevention for US women. Furthermore, women who perceive themselves to be at least somewhat likely to be HIV positive have a higher probability of using a condom to prevent sexually transmitted disease, and women who perceive their partners to be HIV positive are twice as likely as other women to use a condom for STD prevention. However, women who consider themselves likely to be HIV positive are no more likely to use a condom than those who consider themselves not at risk. 相似文献
996.
Both treatment efficacy and safety are typically the primary endpoints in Phase II, and even in some Phase III, clinical trials. Efficacy is frequently measured by time to response, death, or some other milestone event and thus is a continuous, possibly censored, outcome. Safety, however, is frequently measured on a discrete scale; in Eastern Cooperative Oncology Group clinical trial E2290, it was measured as the number of weekly rounds of chemotherapy that were tolerable to colorectal cancer patients. For the joint analysis of efficacy and safety, we propose a non-parametric, computationally simple estimator for the bivariate survival function when one time-to-event is continuous, one is discrete, and both are subject to right-censoring. The bivariate censoring times may depend on each other, but they are assumed to be independent of both event times. We derive a closed-form covariance estimator for the survivor function which allows for inference to be based on any of several possible statistics of interest. In addition, we derive its covariance with respect to calendar time of analysis, allowing for its use in sequential studies. 相似文献
997.
We investigate the effect of unobserved heterogeneity in the context of the linear transformation model for censored survival
data in the clinical trials setting. The unobserved heterogeneity is represented by a frailty term, with unknown distribution,
in the linear transformation model. The bias of the estimate under the assumption of no unobserved heterogeneity when it truly
is present is obtained. We also derive the asymptotic relative efficiency of the estimate of treatment effect under the incorrect
assumption of no unobserved heterogeneity. Additionally we investigate the loss of power for clinical trials that are designed
assuming the model without frailty when, in fact, the model with frailty is true. Numerical studies under a proportional odds
model show that the loss of efficiency and the loss of power can be substantial when the heterogeneity, as embodied by a frailty,
is ignored.
An erratum to this article can be found at 相似文献
998.
999.
Population and Environment - 相似文献
1000.
Morrison Melanie A. Morrison Todd G. Pope Gregory A. Zumbo Bruno D. 《Social indicators research》1999,48(1):39-49
Working from the Principle of Beneficence we make the case that there is a need for adequate measures of sexism in men and women. Swim, Aikin, Hall and Hunter (1995) suggest that modern sexism represents a constellation of beliefs in which individuals: (a) disavow women's present-day discrimination; (b) reject women's demands for political and economic power; and (c) disapprove of policies designed to promote gender equality. To assess this construct, Swim et al. (1995) developed the Modern Sexism Scale (MSS), and to date, few studies have assessed its reliability and factor structure. Using data from 187 Canadian participants, confirmatory factor analysis was used to assess the unidimensionality of the MSS and Swim and associates' (1995) Old-Fashioned Sexism Scale (OFSS). Results do not support Swim et al.'s conceptualization of modern sexism as a unidimensional construct; however, the OFSS fit a unidimensional model. The implications of these findings are discussed. 相似文献