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41.
Using cluster analysis, 789 predominately Latino and African American high school youth were classified into varying academic at‐risk profiles using self‐reported levels of academic confidence, motivation to attend school, perceived family support, connections with teachers and peers, and exposure to violence. Six clusters emerged, 5 of which were identified as “at‐risk.” The clusters were examined in relation to academic stress, health status, grades, and school retention. Exposure to violence was one distinguishing feature of youth identified as most vulnerable, vulnerable, and resilient; however, youth identified as resilient recorded better academic outcomes.  相似文献   
42.
In the paper we present a new method of calculating sampling intervals, so-called windows, allowing an experimenter some flexibility in timing the sample collection, while a minimum required design efficiency for parameter estimation is assured. The method is based on the Equivalence Theorem for D-optimality what makes the length of each window related to the parameter sensitivities. An example of calculating the windows in a pharmacokinetic study is presented. Some other methods of calculating efficient sampling windows are briefly discussed.  相似文献   
43.
Over the first years of life, infants gradually develop the ability to retrieve their memories across cue and contextual changes. Whereas maturational factors drive some of these developments in memory ability, experiences occurring within the learning event may also impact infants' ability to retrieve memories in new situations. In 2 experiments we examined whether it was possible to facilitate 12‐month‐old infants' generalization of learning in the deferred imitation paradigm by varying experiences before or during the demonstration session, or during the retention interval. In Experiment 1, altering the length, timing, or variability of training had no impact on generalization; infants showed a low, but consistent level of memory retrieval. In Experiment 2, infants who experienced a unique context for encoding and retrieval exhibited generalization; infants who experienced the context prior to the demonstration session, or during the retention interval, did not. Specificity is a robust feature of infant memory and is not substantially altered by encoding experiences in an observational learning paradigm. Previous history with a learning environment can, however, impact the flexibility of memory retrieval.  相似文献   
44.
The authors explored predictions of general job satisfaction at early and middle adulthood and uncovered several findings about developmental processes associated with job satisfaction. Tests of life‐span career theory propositions revealed that neither choice‐job congruence nor gender added significantly to predictions of job satisfaction at 2 career stages. Earlier occupational choice and current job added to predictions of midcareer (modal age 43 years) job satisfaction, especially for men. The predictability of job satisfaction is apparently influenced by the career stage when satisfaction is appraised.  相似文献   
45.
We examine the relationship between neighborhood structural characteristics, social organization, and the sexual partnering practices of adults. Analyses of 1990 census and 1995–1997 survey‐based data on Chicago neighborhoods and adult sexual activity reveal for men a number of neighborhood influences on sexual partnering practices. First, residential stability is negatively associated with having a short‐term sexual partner in the last year. Second, neighborhood social ties are positively associated with short‐term sexual partnering in neighborhoods with low levels of collective efficacy—the combination of cohesion and shared expectations for beneficial action among neighbors—but this effect is substantially reduced as collective efficacy increases. Moreover, neighborhood collective efficacy and social ties mediate the effect of residential stability on sexual partnering practices. Neighborhood characteristics were not associated with short‐term sexual partnering for women.  相似文献   
46.
It is more than 10 years since the Special Educational Needs Tribunal was established in 1994 as an independent panel which arbitrates in disputes between parents of children with the label special educational needs and Local Education Authorities (LEAs) in England. In 2002 the Tribunal began hearing claims for disability discrimination and was re-named the Special Educational Needs and Disability Tribunal (SENDisT). Since 1994 over 20,000 appeals have been registered. This article, which forms part of my ongoing Ph.D. thesis 'Parents as advocates: the experience of parents who register an appeal with SENDisT', offers an analysis of parents' Tribunal stories. Here, the key question is what affect the process of going to SENDisT has on the social, emotional and financial well-being of the family. Through a process of narrative inquiry the aim is to foreground parents' unheard stories and to reveal their 'hidden' experiences.  相似文献   
47.
This is an analysis of the social context of normal police lies. We define lies as speech acts which the speaker knows are misleading or false, are intended to deceive, and where evidence to the contrary is known to the observer. Lies are relative to a moral context, and what an audience will accept. Lies include excuses, which deny full responsibility for an act, but acknowledge its immorality, and justifications, which accept responsibility but deny blame-worthiness. Police learn to lie and to carefully distinguish normal (or acceptable) lies from unacceptable lies, suggesting that lies are a part of a negotiated occupational order. We show how and why some types of lies are rewarded by police using ethnographic data from an 18 month field study of a large urban force. Lies can be of little issue, or become troublesome. We report and analyze two kinds of troublesome lies: case lies, recognized stories an officer utilizes in a courtroom or on paper to facilitate the conviction of a suspect, and cover stories, lies an officer tells in court, to supervisors, and on the job with the aim of providing a verbal shield or mitigation in the event of discipline. Both excuses and justifications are woven together in these vignettes. An example of a refusal to lie is used to illustrate some of the limits on lying as well organizational factors in lying. Some implications for official lying are also noted.  相似文献   
48.
49.
Marriage and fertility in the United States have become less firmly entwined as more women bear children without marrying and more couples with children divorce. Today a sizeable number of children are expected to spend a portion of their childhood in one-parent households. Despite the trends in illegitimacy and divorce, the actual effect of out-of-wedlock childbearing on the living arrangements of children has not been fully explicated. Using the National Survey of Family Growth Cycle III, this paper estimates the probability that children aged 0–13 in 1982 are living in two-parent households, controlling for their mothers' marital statuses at their births. We find that marital status at birth is an important predictor of household structure at later ages for both white and black populations; however, the childhood environment is actually quite elastic as women marry, divorce, remarry, and redivorce.  相似文献   
50.
The contemporary retreat from marriage in the United States has had a differential impact across socioeconomic and racial groups. Here, 1990 marriage rates and propensities for Virginia, North Carolina, and Wisconsin are analyzed regarding (a) the likelihood that persons in different groups ever marry and (b) patterns of partner choice with respect to race and educational level. Marriage remains strong in most race‐education groups but is substantially lower among Blacks and among those with less than 12 years of education. Patterns of partner choice have shifted to show greater symmetry between the educational levels of brides and grooms. Changes have been modest with regard to the level and pattern of interracial (Black‐White) marriage. Marriage is increasingly a union of equals, but a union chosen more by Whites than by Blacks and more by the well educated than by the poorly educated.  相似文献   
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