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41.
The rural-urban gap in infant mortality rates is explained by using a new decomposition method that permits identification of the contribution of unobserved heterogeneity at the household and the community level. Using Demographic and Health Survey data for six Francophone countries in Central and West sub-Saharan Africa, we find that differences in the distributions of factors that determine mortality-not differences in their effects-explain almost the entire gap. Higher infant mortality rates in rural areas mainly derive from the rural disadvantage in household characteristics, both observed and unobserved, which explain two-thirds of the gap. Among the observed characteristics, environmental factors-a safe source of drinking water, electricity, and quality of housing materials-are the most important contributors. Community characteristics explain less than onequarter of the gap, with about two-thirds of this coming from community unobserved heterogeneity and one-third from the existence of a health facility within the community. The effect of disadvantageous environmental conditions-such as limited electricity and water supply-derives both from a lack of community-level infrastructure and from the inability of some households to exploit it when available. Policy needs to operate at both the community and household levels to correct such deficiencies.  相似文献   
42.
Models of party competition building on Downs (1957) have recognized that there are centrifugal and centripetal forces in party competition; but one such force, the existence of party primaries, has been remarkably neglected in recent literature. We consider party/candidate policy divergence in two-party competition in one dimension where there is a two-stage electoral process, e.g., a primary election (or caucus) among party supporters to select that party’s candidate followed by a general election. We develop a model in which (some or all) voters in the primary election are concerned with the likelihood that the primary victor will be able to win the general election and being concerned with that candidate’s policy position. This model is similar in all but technical details to that given in an almost totally neglected early paper in Public Choice Coleman (1971) 11:35–60, but we offer important new results on electoral dynamics for candidate locations. In addition to accounting for persistent party divergence by incorporating a more realistic model of the institutions that govern elections in the U.S., the model we offer gives rise to predictions that match a number of important aspects of empirical reality such as frequent victories for incumbents and greater than otherwise expected electoral success for the minority party in situations where that party has its supporters more closely clustered ideologically than the supporters of the larger party (in particular, with a concentration of voters between the party mean and the population mean).A much earlier version of this paper was presented at the Annual Meeting of the Public Choice Society, Long Beach, California, March 24–26, 1995. We are indebted to Dorothy Green and to Clover Behrend-Gethard for bibliographic assistance and to Nicholas Miller and the late Peter Aranson for helpful suggestions.  相似文献   
43.
Owen  Robert  Ntoko  Alfred  Zhang  Ding  Dong  June 《Social indicators research》2002,60(1-3):179-190
Marketers have traditionally studied diffusionof innovation with a primary focus on theindividual consumer as a unit of analysis, themajor types of findings being characteristicsof adopter categories and opinion leadership. We propose that this perspective is notadequate from a macromarketing perspective, inwhich the goals are to set public policy forsocietal good or to create an environment whichenables the diffusion of an innovation in a waythat no single marketer could do alone. Insetting public policy which can enable (orinhibit) diffusion of innovation for societalgood, a system composed of a mass socialinfrastructure, a competitive infrastructure,and a technical infrastructure should beconsidered.  相似文献   
44.
The current study examined the effectiveness of the Prevention and Relationship Enhancement Program (PREP) with lower-income and racial/ethnic minority (African American and Latino/a) couples. Additionally, we tested whether relationship outcomes varied based on the delivery format (i.e., group format vs. couple format). The sample included 321 unmarried couples expecting a child or who have a child 3 month old or younger. The couples participated in 16 hr of PREP via a group or a couple format over the course of 2-3 months. Couples relationship quality was assessed prior to and directly after the program. The results showed that men and women demonstrated significant gains in their communication skills, relationship functioning, friendship, dedication, and relationship confidence. Couples who participated in PREP via the couple format had better outcomes on three of the seven relational outcomes as compared to couples who participated in PREP via the group format.  相似文献   
45.
    
Couple relationship education (CRE) programs are associated with positive romantic relationship outcomes; however, the mechanisms by which these gains occur are less understood. The current study (122 couples) utilized actor–partner modeling to examine the association between the therapeutic alliance and dedication and negative and positive communication for racial/ethnic minority couples. Additionally, we examined whether gender and delivery format moderated these relationships. Results demonstrated that both men's and women's alliance scores were significantly related to their own outcomes. Higher ratings of alliance were related to partner outcomes for men only. The association between partners' alliance and dedication outcomes was stronger within the group format as compared to the couple format. Implications for leaders of CRE programs are offered.  相似文献   
46.
    
Couple relationship education (CRE) programs are intended to prevent negative couple outcomes, however, some evidence suggests couples in greater distress may still benefit. The current study examined pre‐ and postchanges in relationship functioning of 362 low‐income African American and Hispanic couples. Outcomes (dedication and communication) were assessed by examining differences between two distinct groupings of couples; distressed (both partners reporting clinically significant distress) and nondistressed (neither partner reporting clinically significant distress) couples. Distressed couples at predemonstrated large‐sized gains in all outcome variables, as compared to nondistressed couples. Those who participated in the single‐couple format demonstrated lower gains in positive communication as compared to those in the group format. Implications for distressed couples in CRE programs are offered.  相似文献   
47.
    
After friends and relatives, childminders are the most common form of child care. This paper reports the results from a postal survey of a nationally representative sample of over 1,000 childminders. Results are reported concerning childminders' training and employment histories, working conditions, motivation, commitment and satisfaction with their work. Two groups of childminders emerge; a group where childminding may be a passing phase in their employment career and a group who consider it as a long‐term career. The findings are discussed with reference to the aims of the National Childcare Strategy and the role of Early Years Development and Childcare Partnerships. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
48.
    
Drawing from six years of ethnographic field research, I examine participants' involvement in bluegrass music and festival culture in the American West. Participants left their community‐starved home neighborhoods to cultivate what I refer to as “portable communities”: temporary forms of mobile gemeinschaft community that participants found in multiple settings. Festivalgoers articulated a consistent vocabulary of intimacy, inclusion, and simplicity when describing their continued involvement in this setting. They described their involvement as driven by a quest for intimate community, open and equal social relations, and simple living, elements they found in short supply in their daily lives. Whereas traditional community forms depend on residential stability, these participants intentionally cultivated and supported alternatives that emerged in response to participants' geographic mobility.  相似文献   
49.
    
Routine child care by grandparents was examined for 1,229 children who were participants in the National Institute of Child Health and Human Development (NICHD) Study of Early Child Care. Four groups were identified: extended full‐time care, extended part‐time care, sporadic care, and no routine care during the first three years. The odds of sporadic child care by grandparents were higher when mothers were relatively young and worked nonstandard hours. The odds of extended full‐time grandparent care versus extended part‐time grandparent care were higher for mothers of color and mothers with more extensive full‐time employment. All types of grandparent care were more likely when a grandparent lived in the household. These findings suggest that grandparent care is heterogeneous and may occur in response to different family circumstances.  相似文献   
50.
    
One of the most important steps in the design of a pharmaceutical clinical trial is the estimation of the sample size. For a superiority trial the sample size formula (to achieve a stated power) would be based on a given clinically meaningful difference and a value for the population variance. The formula is typically used as though this population variance is known whereas in reality it is unknown and is replaced by an estimate with its associated uncertainty. The variance estimate would be derived from an earlier similarly designed study (or an overall estimate from several previous studies) and its precision would depend on its degrees of freedom. This paper provides a solution for the calculation of sample sizes that allows for the imprecision in the estimate of the sample variance and shows how traditional formulae give sample sizes that are too small since they do not allow for this uncertainty with the deficiency being more acute with fewer degrees of freedom. It is recommended that the methodology described in this paper should be used when the sample variance has less than 200 degrees of freedom.  相似文献   
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