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41.
This study employs a qualitative multiple-case study to explore relational management mechanisms for strategic nonprofit alliances (NPAs) formed by at least 3 nonprofit organizations by examining collaborative relationships among farmers associations in Taiwan. We explore these mechanisms by analyzing case data from four strategic cooperation characteristics, which can best explain NPAs. To effectively sustain partnerships, our findings suggest that an NPA applies acceptable collaborative rules and regulations, common standard procedures, symmetric information and communication, and capability building and corrective measures when cooperation involves high input commonality. The results also suggest empowerment for partners with deeper input commitment to direct decisions on resource distribution and utilization when collaborative ties involve low input measurability. Regarding high output commonality, we advise NPAs to enforce common output quality control, efficient substandard-output treatment, and external incentives as mechanisms to encourage partners for continued commitment. If relationships involve low output measurability, our findings suggest that NPAs heighten partners’ voluntary motivation for the common good, with goal-achievement assessment measures, professional certification by external experts, and acceptable and reasonable benefit-sharing methods  相似文献   
42.
The goal of this study was to examine child and parent predictors of children's hostile attribution bias (HAB) with a particular focus on exploring the associations between parents’ early attribution of child misbehavior and children's HAB in the transition to school age. Participants were 241 children (118 girls) of middle‐income families who were at risk for school‐age conduct problems. Multi‐method, multi‐informant data were collected on maternal attributions of child misbehavior, parental use of corporal punishment, and child attributes (i.e., verbal IQ, effortful control, theory of mind, and emotional understanding) at 3 years, and child HAB in ambiguous situations at 6 years. Results indicated that mothers’ internal explanations for children's misconduct may either reduce or increase children's later HAB depending on the specific content of attributions, such that mothers’ belief that children misbehave because of their internal state (i.e., emotional state or temperament) was associated with lower levels of child HAB, whereas attributing power‐based motives (i.e., manipulative, controlling intentions) in children was associated with higher levels of HAB. The findings are discussed with respect to appreciating the complexity of parents’ explanations for children's behavior, and considering parental cognition as a potential target for early identification and prevention of child HAB and related problems.  相似文献   
43.
Physical activity takes place in different social contexts such as leisure, home, and work. However, the differential associations of these distinct categories of activity with aspects of well-being have rarely been investigated. This study was designed to estimate independent associations of (a) leisure-time, (b) domestic and (c) work-related physical activities with subjective well-being in older adults. A cross-sectional survey was conducted in 2009 with 2,295 community-dwelling older adults aged 65 or older in Kaohsiung, Taiwan. Among them, 307 participants were selected for a 3-year follow-up study in 2012. The results based on cross-sectional and longitudinal analyses demonstrated that leisure-time physical activity, after multivariate adjustment, was positively associated with five dimensions of well-being, including ‘physical’, ‘psychological’, ‘independence’, ‘learning and growth’, and ‘social’ well-being. Household physical activity was positively associated only with ‘social’ well-being. Occupational physical activity was not related to any dimension of well-being. The study suggests that associations between physical activity and dimensions of subjective well-being during later life are dependent on the social context in which the activity takes place. This study indicates that physical activity taken as leisure has greatest potential to enhance the quality of life of older adults.  相似文献   
44.
We revisit the problem of testing homoscedasticity (or, equality of variances) of several normal populations which has applications in many statistical analyses, including design of experiments. The standard text books and widely used statistical packages propose a few popular tests including Bartlett's test, Levene's test and a few adjustments of the latter. Apparently, the popularity of these tests have been based on limited simulation study carried out a few decades ago. The traditional tests, including the classical likelihood ratio test (LRT), are asymptotic in nature, and hence do not perform well for small sample sizes. In this paper we propose a simple parametric bootstrap (PB) modification of the LRT, and compare it against the other popular tests as well as their PB versions in terms of size and power. Our comprehensive simulation study bursts some popularly held myths about the commonly used tests and sheds some new light on this important problem. Though most popular statistical software/packages suggest using Bartlette's test, Levene's test, or modified Levene's test among a few others, our extensive simulation study, carried out under both the normal model as well as several non-normal models clearly shows that a PB version of the modified Levene's test (which does not use the F-distribution cut-off point as its critical value), and Loh's exact test are the “best” performers in terms of overall size as well as power.  相似文献   
45.
For many continuous distributions, a closed-form expression for their quantiles does not exist. Numerical approximations for their quantiles are developed on a distribution-by-distribution basis. This work develops a general approximation for quantiles using the Taylor expansion. Our method only requires that the distribution has a continuous probability density function and its derivatives can be derived to a certain order (usually 3 or 4). We demonstrate our unified approach by approximating the quantiles of the normal, exponential, and chi-square distributions. The approximation works well for these distributions.  相似文献   
46.
为了贯彻《共同纲领》的文教政策,使山东大学顺利实现向新民主主义大学的转变,在建国初期山东大学思想政治教育中,校长华岗为全校师生所授政治大课,采取理论联系实际和以理服人的方针,系统地给山大师生讲授了党的政策和马克思主义基本原理,提高了山大师生的觉悟,为20世纪50年代山大的辉煌奠定了基础。  相似文献   
47.
Mixed-Weibull distribution has been used to model a wide range of failure data sets, and in many practical situations the number of components in a mixture model is unknown. Thus, the parameter estimation of a mixed-Weibull distribution is considered and the important issue of how to determine the number of components is discussed. Two approaches are proposed to solve this problem. One is the method of moments and the other is a regularization type of fuzzy clustering algorithm. Finally, numerical examples and two real data sets are given to illustrate the features of the proposed approaches.  相似文献   
48.
Methods for a sequential test of a dose-response effect in pre-clinical studies are investigated. The objective of the test procedure is to compare several dose groups with a zero-dose control. The sequential testing is conducted within a closed family of one-sided tests. The procedures investigated are based on a monotonicity assumption. These closed procedures strongly control the familywise error rate while providing information about the shape of the dose-responce relationship. Performance of sequential testing procedures are compared via a Monte Carlo simulation study. We illustrae the procedures by application to a real data set.  相似文献   
49.
李凌  常亚青 《社会科学》2012,(10):51-59
新经济地理学视域下,边境不再是人为阻隔生产要素流动的非贸易壁垒,而是促进国际专业化分工和形成循环因果积累效应的天然地理因素。基于新经济地理学的相关理论,研究中印边境贸易的专业化模式和贸易模式以及边境贸易政策对中印边境贸易的影响,以论证中印两国经贸的比较优势在边境地区的空间整合,最终推动中印边境贸易健康发展。  相似文献   
50.
Many tree algorithms have been developed for regression problems. Although they are regarded as good algorithms, most of them suffer from loss of prediction accuracy when there are many irrelevant variables and the number of predictors exceeds the number of observations. We propose the multistep regression tree with adaptive variable selection to handle this problem. The variable selection step and the fitting step comprise the multistep method.

The multistep generalized unbiased interaction detection and estimation (GUIDE) with adaptive forward selection (fg) algorithm, as a variable selection tool, performs better than some of the well-known variable selection algorithms such as efficacy adaptive regression tube hunting (EARTH), FSR (false selection rate), LSCV (least squares cross-validation), and LASSO (least absolute shrinkage and selection operator) for the regression problem. The results based on simulation study show that fg outperforms other algorithms in terms of selection result and computation time. It generally selects the important variables correctly with relatively few irrelevant variables, which gives good prediction accuracy with less computation time.  相似文献   
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