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71.
A probabilistic dealing strategy is proposed which allows all premium brands in an established market to earn nonnegative profits without cooperation. Following the strategy, brands take turns attracting deal-responsive customers. Relative to a reactive competitive strategy, the proposed strategy improves the positions of all premium brands. With use of the strategy, average deal sizes are positively related to a brand's market share, the proportion of quality conscious customers, the proportion of informed customers, the span of regular prices in a market, and the range of customers' acceptable prices.  相似文献   
72.
For convex and concave mathematical programs restrictive constraints (i.e., their deletion would change the optimum) will always be binding at the optimum, and vice versa. Less well-known is the fact that this property does not hold more generally, even for problems with convex feasible sets. This paper demonstrates the latter fact using numerical illustrations of common classes of problems. It then discusses the implications for public policy analysis, econometric estimation, and solution algorithms.  相似文献   
73.
In the study of risks , different sciences use the same category in different ways, each related to its own ontological assumptions. But many of these fields communicate very little with one another. This article seeks to approximate two of these areas of study that have shown similar concerns and that can mutually strengthen one another, namely, geography and demography. Geography was one of the first disciplines to include risk in its environmental dimension and has had broad experience in simultaneously focusing on social and natural dynamics. Demography, on the other hand, faces greater difficulties because only recently has it incorporated the environmental dimension into its scientific scope. Both have brought the concept of vulnerability into their conceptual framework as complementary to that of risk. Geographers understand vulnerability as a more symbiotic form of the relationship between society and nature, whereas demographers give it a strong socioeconomic component. In this regard, the conceptual discussion on risks and vulnerabilities, in its attempt at approximating these two fields, is a way of conceptually advancing and strengthening the different approaches to empirical work, especially in population–environment studies which is the common ground for the dialogue between the two disciplines.
Daniel Joseph HoganEmail:
  相似文献   
74.
This article describes an algorithm used to formulate an inbound consolidation strategy when multi-items are replenished in groups and when total logistics cost is to be minimized. The importance of this algorithm is threefold (1) no optimal procedure exists for grouping multi-items when minimizing total logistics cost, (2) a complete enumeration of all possible groups (from which the optimal grouping set can be identified) is impractical due to the combinatorial nature of the grouping problem, and (3) no other heuristics have been developed that adequately reflect shipping cost in the analysis like this one does. We report the experience of using this algorithm to group and reorder 75 selected ensembles containing a total of 517 inventory items of a retail merchandising firm.  相似文献   
75.
This study explored parenting styles and values internalization. Perceived parenting styles were measured in Grade 7 (n = 749) and Grade 12 (n = 468), and values were measured in Grade 12 (n = 271) and one year postschool (n = 291). We measured three aspects of valuing: priority (extrinsic, intrinsic importance); regulation (controlled, autonomous); and successful enactment of values (success). Mothers’ authoritative parenting in Grade 7 predicted increased importance and autonomous regulation of values one year postschool. Fathers’ authoritative parenting in Grade 7 predicted decreased importance of extrinsic values. Fathers’ permissive parenting in Grade 7 predicted decreased importance of intrinsic values. Authoritarian parenting in Grade 12 predicted more controlled values regulation postschool, particularly for extrinsic values. Parenting in early and late adolescence predicts values internalization in emerging adulthood.  相似文献   
76.
Following previous work on inequality in health opportunity, this paper attempts to determine the contribution of circumstances, efforts and lifestyle, and demographic variables to the overall inequality in health in Luxembourg. Health is measured via the answers given to a question on self-assessed health and is considered as an ordinal variable. The educational level of each parent, the financial situation of the family during childhood, the area of birth of the individual, and of his/her parents, and the year of immigration are considered as circumstances. Effort and lifestyle variables are proxied by information on the educational level of the individual, whether he/she smoked and whether he/she had a physical activity on a regular basis. Sex and age are considered as demographic variables. To solve the issue of correlation between circumstances and effort and lifestyle the estimation is implemented in two stages. In the first stage, each effort and lifestyle variable is regressed in a separate equation against the vector of circumstances and demographic variables and, in a second stage, the individual health status is regressed against the vector of circumstances and demographic variables along with the estimated residuals of the effort equations described previously. The respective impacts of the three categories of explanatory variables (circumstances, effort and lifestyle and demographic variables) on health inequality are derived via a Shapley decomposition of the likelihood ratio of the health ordered logit regression. It appears that differences in circumstances and effort and lifestyle explain each around a quarter of this likelihood ratio.  相似文献   
77.
This study illuminates the association between cigarette smoking and adult mortality in the contemporary United States. Recent studies have estimated smoking-attributable mortality using indirect approaches or with sample data that are not nationally representative and that lack key confounders. We use the 1990–2011 National Health Interview Survey Linked Mortality Files to estimate relative risks of all-cause and cause-specific mortality for current and former smokers compared with never smokers. We examine causes of death established as attributable to smoking as well as additional causes that appear to be linked to smoking but have not yet been declared by the U.S. Surgeon General to be caused by smoking. Mortality risk is substantially elevated among smokers for established causes and moderately elevated for additional causes. We also decompose the mortality disadvantage among smokers by cause of death and estimate the number of smoking-attributable deaths for the U.S. adult population ages 35+, net of sociodemographic and behavioral confounders. The elevated risks translate to 481,887 excess deaths per year among current and former smokers compared with never smokers, 14 % to 15 % of which are due to the additional causes. The additional causes of death contribute to the health burden of smoking and should be considered in future studies of smoking-attributable mortality. This study demonstrates that smoking-attributable mortality must remain a top population health priority in the United States and makes several contributions to further underscore the human costs of this tragedy that has ravaged American society for more than a century.  相似文献   
78.
Child welfare supervision is fundamental to advancing the quality of practice when seeking to ensure the safety, permanency, and well-being of children. Child welfare supervisors serve administrative, educational, and support functions as they oversee frontline caseworkers and direct service providers. Clinical supervision, a dialog-driven process of case review and consultation is situated within the educational function. The process of clinical supervision is essential to child welfare practice, because it prompts reflection and builds analytical thinking skills needed to address complex situations involved in child protection. Despite increased recognition regarding the importance of clinical supervision, child welfare supervision continues to focus primarily on administrative tasks. Organizational climate and external pressures push this administrative agenda. In addition, many child welfare supervisors lack experience, training, and therefore competency in facilitating clinical case reviews. Strengths-Based Supervision (SBS; Lietz 2013) is a model of clinical supervision that was developed to (a) increase child welfare supervisors’ intentionality regarding the importance of infusing clinical supervision into child welfare supervision and (b) advance the skills needed to implement this practice effectively representing one solution to this ongoing challenge.  相似文献   
79.
Research suggests the relationship between pleasure and condom use during penile–vaginal intercourse (PVI) is associated with relationship status. This online study examined pleasure ratings and condom use at last PVI, stratifying by partner type, among a national sample of Canadian university students. Participants were 715 undergraduates (60.7% women, 39.3% men) who reported on their most recent sexual experience. Condom use decreased with level of relationship commitment, whereas ratings of pleasure increased. Overall, participants were more likely to rate their most recent PVI as Very pleasurable when condoms were not used compared to when condoms were used. However, when stratified by partner type, these differences largely disappeared. For women, with one exception, there were no differences in pleasure between PVI with and without condoms across most partner-type categories. Women in committed dating relationships were more likely to report their last PVI as very pleasurable if condoms were not used than women in these same relationships who had used condoms. Across relationship categories, men who did and did not use condoms did not differ in terms of their pleasure ratings. The results of this study suggest relationship context should be taken into account when assessing condom use experiences.  相似文献   
80.
Commuters' lives have become more complicated with rising income. In my model, transportation mode choices are made simultaneously with the choice of whether to make multiple stops. Using travel behavior data, I estimate the model using an error components logit (ECL) specification to account for commuters' unobserved preferences for particular modes and find that omitting unobserved preferences underestimates value of travel time relative to the crossing‐components ECL. The estimated model predicts that increased trip complexity causes substitution away from public transit to automobiles, with the exception that bicyclists transition only to more complex trips and do not change transportation modes. (JEL R41, C25)  相似文献   
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