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151.
ABSTRACT

The present study investigated the prevalence of gambling behaviors among 71 individuals recovering from substance-dependent disorders and living in self-run recovery homes (Oxford Houses). Residents were given the South Oaks Gambling Screen to assess gambling behaviors and pathological gambling, and 19.7% of the sample was identified as having probable pathological gambling. These residents reported proportionately more involvement in a variety of gambling behaviors than other residents. Engagement in various gambling activities was consistent with previous investigations and suggested that self-run recovery homes such as Oxford Houses might be suitable referral sources for recovering persons who have comorbid gambling problems.  相似文献   
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Overdispersion is a problem encountered in the analysis of count data that can lead to invalid inference if unaddressed. Decision about whether data are overdispersed is often reached by checking whether the ratio of the Pearson chi-square statistic to its degrees of freedom is greater than one; however, there is currently no fixed threshold for declaring the need for statistical intervention. We consider simulated cross-sectional and longitudinal datasets containing varying magnitudes of overdispersion caused by outliers or zero inflation, as well as real datasets, to determine an appropriate threshold value of this statistic which indicates when overdispersion should be addressed.  相似文献   
155.
We explored the role that exogenous and endogenous competitors for attention play in infants’ abilities to encode and retain information over a 6‐month period. Sixty‐six children visited the laboratory at 15 months, and 32 returned for a second visit at 21 months. Children observed models of conventional‐ relation and enabling‐relation action sequences. Half the children were distracted by a “Mister Monkey” mechanical toy during the conventional‐relation sequence, while the other half was distracted during the enabling‐relation sequence. The Early Childhood Behavior Questionnaire indexed endogenous factors at both ages. Immediate postmodel production of target actions indexed encoding efficiency, and 6‐month production of target actions indexed long‐term recall. The exogenous distracter impacted encoding efficiency (i.e., immediate recall), but not long‐term recall. Endogenous factors (i.e., temperament) were primarily associated with long‐term recall. Of special interest was our finding that endogenous factors, especially surgency, moderated the effect of the exogenous distracter. It appears that when learning conventional‐relation sequences in the presence of exogenous distracters, surgency mobilizes attentional resources toward the learning objective; however, when learning enabling‐relation sequences under the same conditions, surgency either boosts the saliency of the distracters or boosts children’s susceptibility to them.  相似文献   
156.
ABSTRACT

Understanding human development among the oldest old is a sequential building process taking into account building-block data, theories, and models from childhood, adulthood, and old age toward a new territory of oldest-old survivors who have lived way beyond the average life-span. A central question is whether the oldest-old survivors have developed specific survival techniques and/or protective environments that nurture survival. Or are the oldest old statistical outliers who by happenstance continue to survive further into old age? This commentary provides a historical framework on the papers in this series that describe challenges confronted by the oldest-old survivors in order to advance our understanding of survival of the oldest old. A clear understanding of the contributors to longevity could guide public policies toward well-being and life satisfaction among our oldest-old citizens.  相似文献   
157.
Homeless youth represent a vulnerable and understudied population. Little research has prospectively identified factors that may place youth at risk for experiencing homelessness. The current study utilizes data from the National Longitudinal Survey of Youth-97 (NLSY-97) to examine predictors of experiencing homelessness as a young adult (before age 25). The NLSY-97 includes a nationally representative sample of 8984 youth. Data were first collected from these youth when they were between the ages of 12 and 18 years. The current study examined whether individual and family risk factors reported during adolescence predict homelessness by the age of 25. The findings showed that multiple runaway episodes, nontraditional family structure, lower educational attainment, and parental work limitations due to health increased the risk of homelessness. A permissive parenting style and being Hispanic protected against homelessness. This study offers unique insight into risk and protective factors for youth homelessness and has important clinical implications.  相似文献   
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159.
Sociology of Sport: an Overview   总被引:1,自引:0,他引:1  
This review sketches some strengths and weaknesses in the subfield and its potential for generating and testing theoretical frameworks. The analysis includes research on sport from the following perspectives: interinstitutional relationships, social stratification, small groups, and social psychology. In recent years, the sociology of sport has become more sophisticated in terms of research questions posed, research design, quantitative analysis, and cross-cultural comparisons. As one dimension of leisure, sports represent a serious topic for scholarly research to round out our understanding of the human person as a social being.  相似文献   
160.
We study inventory optimization for locally controlled, continuous‐review distribution systems with stochastic customer demands. Each node follows a base‐stock policy and a first‐come, first‐served allocation policy. We develop two heuristics, the recursive optimization (RO) heuristic and the decomposition‐aggregation (DA) heuristic, to approximate the optimal base‐stock levels of all the locations in the system. The RO heuristic applies a bottom‐up approach that sequentially solves single‐variable, convex problems for each location. The DA heuristic decomposes the distribution system into multiple serial systems, solves for the base‐stock levels of these systems using the newsvendor heuristic of Shang and Song (2003), and then aggregates the serial systems back into the distribution system using a procedure we call “backorder matching.” A key advantage of the DA heuristic is that it does not require any evaluation of the cost function (a computationally costly operation that requires numerical convolution). We show that, for both RO and DA, changing some of the parameters, such as leadtime, unit backordering cost, and demand rate, of a location has an impact only on its own local base‐stock level and its upstream locations’ local base‐stock levels. An extensive numerical study shows that both heuristics perform well, with the RO heuristic providing more accurate results and the DA heuristic consuming less computation time. We show that both RO and DA are asymptotically optimal along multiple dimensions for two‐echelon distribution systems. Finally, we show that, with minor changes, both RO and DA are applicable to the balanced allocation policy.  相似文献   
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