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61.
A need exists to better understand how racial/ethnic minority students' critical consciousness development in response to marginalization may be involved in their educational and career development. We therefore examined the link between critical consciousness development and career decision self-efficacy and career outcome expectations among racial/ethnic minority community college students. Following social cognitive career theory's conceptual pillars, we developed a testable model integrating critical consciousness and social cognitive variables. This model was tested with 135 racially and ethnically diverse community college students. Data analysis included path analyses and tests of model fit using structural equation modeling. Results suggested that (a) higher critical agency is linked to higher career decision self-efficacy and outcome expectations and (b) critical action and reflection have a bidirectional link and predict higher critical agency. Implications for research and practice aiming to close educational and career gaps among racial/ethnic minorities are discussed.  相似文献   
62.
Qualitative Sociology -  相似文献   
63.
Social Indicators Research -  相似文献   
64.
When prediction intervals are constructed using unobserved component models (UCM), problems can arise due to the possible existence of components that may or may not be conditionally heteroscedastic. Accurate coverage depends on correctly identifying the source of the heteroscedasticity. Different proposals for testing heteroscedasticity have been applied to UCM; however, in most cases, these procedures are unable to identify the heteroscedastic component correctly. The main issue is that test statistics are affected by the presence of serial correlation, causing the distribution of the statistic under conditional homoscedasticity to remain unknown. We propose a nonparametric statistic for testing heteroscedasticity based on the well-known Wilcoxon''s rank statistic. We study the asymptotic validation of the statistic and examine bootstrap procedures for approximating its finite sample distribution. Simulation results show an improvement in the size of the homoscedasticity tests and a power that is clearly comparable with the best alternative in the literature. We also apply the test on real inflation data. Looking for the presence of a conditionally heteroscedastic effect on the error terms, we arrive at conclusions that almost all cases are different than those given by the alternative test statistics presented in the literature.  相似文献   
65.
An accurate procedure is proposed to calculate approximate moments of progressive order statistics in the context of statistical inference for lifetime models. The study analyses the performance of power series expansion to approximate the moments for location and scale distributions with high precision and smaller deviations with respect to the exact values. A comparative analysis between exact and approximate methods is shown using some tables and figures. The different approximations are applied in two situations. First, we consider the problem of computing the large sample variance–covariance matrix of maximum likelihood estimators. We also use the approximations to obtain progressively censored sampling plans for log-normal distributed data. These problems illustrate that the presented procedure is highly useful to compute the moments with precision for numerous censoring patterns and, in many cases, is the only valid method because the exact calculation may not be applicable.  相似文献   
66.
This paper develops a novel and efficient algorithm for Bayesian inference in inverse Gamma stochastic volatility models. It is shown that by conditioning on auxiliary variables, it is possible to sample all the volatilities jointly directly from their posterior conditional density, using simple and easy to draw from distributions. Furthermore, this paper develops a generalized inverse gamma process with more flexible tails in the distribution of volatilities, which still allows for simple and efficient calculations. Using several macroeconomic and financial datasets, it is shown that the inverse gamma and generalized inverse gamma processes can greatly outperform the commonly used log normal volatility processes with Student’s t errors or jumps in the mean equation.  相似文献   
67.
The adolescent transition begins with the onset of puberty which, upstream in the brain, is initiated by the gonadotropin‐releasing hormone (GnRH) pulse generator that activates the release of peripheral sex hormones. Substantial research in human and animal models has revealed a myriad of cellular networks and heritable genes that control the GnRH pulse generator allowing the individual to begin the process of reproductive competence and sexual maturation. Here, we review the latest knowledge in neuroendocrine pubertal research with emphasis on genetic and epigenetic mechanisms underlying the pubertal transition.  相似文献   
68.
Urban Ecosystems - Latin America and the Caribbean (LAC) is one of the most urbanized and biologically diverse regions in the world but is often characterized by weak environmental governance and...  相似文献   
69.
Objective: To describe sexual practices in Mexican lesbian and bisexual women. Materials and method: An online survey was conducted with a nonprobabilistic sample of self-identified lesbian (n?=?768) and bisexual (n?=?371) women from the 32 states of Mexico. Results: Lesbians less frequently reported having had sex with a man than bisexual women. Preferred sexual practices with other women were external genital stimulation with fingers, internal genital stimulation with fingers, and oral genital stimulation. Most (~80%) participants did not use protection to prevent sexually transmitted infections. Conclusions: Our results can inform the design of promotion and prevention programs in sexual health aimed at sexual minority women.  相似文献   
70.

We analyze cooperation of individuals in a family context, using a Public Good game. In a lab experiment, 165 individuals from 55 three-generation families (youth, parent, and grandparent) play a repeated Public Good game in three different treatments: one in which three members of the same family play each other (family), a second with the youth and two non-family members, while preserving the previous generational structure (inter-generational), and a third in which three randomly-selected players play each other (random). We find that all the age groups cooperate more when playing with relatives, indicating that family ties may have a positive relationship to contributions to the Public Good. We also find that this trend is more evident for the youths and the parents than for the grandparents. Furthermore, young individuals tend to cooperate less than older generations, especially in non-family treatments. Our results serve as evidence of the relationship between family ties and inter-generational cooperative behaviors.

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