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91.
Despite a growing number of anthropological studies of deaf communities, little attention has been paid to how socioeconomic and cultural factors influence the experiences and the concerns of hearing parents of deaf and hearing-impaired (DHI) children. This study draws on interviews with parents (and some grandparents) of DHI children in Ecuador, a country marked by profound inequality but also by considerable recent progress in poverty reduction and enhanced provisions for people with disabilities. Despite progress, many carers are nevertheless critical of the way in which new measures have been implemented, and of the schooling available to their child. They are also worried by their child’s vulnerability, the likelihood of discrimination, and the possibility of abuse.  相似文献   
92.
Market segmentation is accepted as a fundamental concept in marketing and several authors have recently proposed a segmentation model where personal and environmental variables intersect with each other to form motivating conditions that drive behavior and preferences. This model of segmentation has been applied to packaged goods. This paper extends this literature by proposing a segmentation model for low-penetration and low involvement (LP-LI) products. An application to the lottery games in Chile supports the proposed model. The results of the study show that in this type of products (LP-LI), the attitude towards the product category is the most important factor that distinguishes consumers from non consumers, and heavy users from light users, and consequently, a critical segmentation variable. In addition, a cluster analysis shows the existence of three segments: (1) the impulsive dreamers, who believe in chance, and in that lottery games can change their life, (2) the skeptical, that do not believe in chance, nor in that lottery games can change their life and (3) the willing, who value the benefits of playing.  相似文献   
93.
Objective.?The aim of the present study was to analyse the effect of testosterone therapy on bone mineral density in healthy elderly men who had low levels of total testosterone.

Design.?Randomized, double-blind, placebo-controlled study.

Participants.?Forty-eight men over 60 years old with decreased testosterone levels (≤320 ng/dL) comprised the study. Twenty-five out of 48 received intramuscular injections of testosterone enanthate every three weeks during 12 months; the remaining 23 participants formed the control group. All participants had measurements of bone mineral density (BMD) in both lumbar spine and hip before and at the end of the study as well as testosterone and 17-β estradiol levels.

Results:?Testosterone treated group exhibited a significant (p < 0.05) increment (from 1.198 ± 0.153 to 1.240 ± 0.141 g/cm2) in lumbar BMD in parallel with a significant (p < 0.001) increment (from 301 ± 32 to 471 ± 107 ng/dL) in testosterone concentrations, whereas no significant change occurred in femoral neck BMD.

Conclusions.?Testosterone therapy elicited a positive effect only in lumbar BMD in elderly men with diminished testosterone serum levels.  相似文献   
94.
ABSTRACT

Massive demonstrations are the staple of powerful social movements, but research on the factors affecting the size of demonstrations (in terms of number of attendants) is almost nonexistent. Why do some demonstrations pack long avenues with masses of people while other ones barely fill a street corner? Combining resource mobilization, political opportunity, and framing theories, we argue that mobilization strategies – the sequence of decisions and actions taken by protest organizers before staging a protest – shape demonstration size. Multivariate models with 937 Chilean demonstrations between 2000 and 2012 show that demonstrations are larger when they display more demands (especially universalistic demands), target the national government, attract more organizations (especially umbrella organizations), and mobilize cohesive groups with broad public support. We reinforce the internal validity of our argument using interviews with movement leaders and secondary research on Chilean society.  相似文献   
95.
Schools offer a convenient setting for research on adolescents. However, obtaining active written parental consent is difficult. In a 6th-grade smoking study, students were recruited with two consent procedures: active consent (parents must provide written consent for their children to participate) and implied consent (children may participate unless their parents provide written refusal). Of 4,427 invited students, 3,358 (76%) provided active parental consent, 420 (9%) provided active parental refusal, and 649 (15%) provided implied consent (parental nonresponse). The implied consent procedure recruited more boys, African Americans, students with poor grades, and smokers. This dual-consent procedure is useful for collecting some limited data from students who do not provide active consent or refusal.  相似文献   
96.
This work deals with two methodologies for predicting incurred but not reported (IBNR) actuarial reserves. The first is the traditional chain ladder, which is extended for dealing with the calendar year IBNR reserve. The second is based on heteroscedastic regression models suitable to deal with the tail effect of the runoff triangle – and to forecast calendar year IBNR reserves as well. Theoretical results regarding closed expressions for IBNR predictors and mean squared errors are established – for the case of the second methodology, a Monte Carlo study is designed and implemented for accessing finite sample performances of feasible mean squared error formulae. Finally, the methods are implemented with two real data sets. The main conclusions: (i) considering tail effects does not imply theoretical and/or computational problems; and (ii) both methodologies are interesting to design softwares for IBNR reserve prediction.  相似文献   
97.
98.
Abstract

In the last decades, sustainable concerns have increasingly gained importance to organizational survival, and Lean/Six Sigma approaches are becoming more and more outstanding in order to improve sustainability performance. This article aims to evaluate the degree of importance of sustainable performance measures of Brazilian organizations and to propose guidelines to achieve sustainability by aligning these measures with operational improvement programmes. Multiple data collection methods were applied as theoretical literature review, questionnaire survey and semi-structured interviews with industry professionals and academic researchers. The findings show that it is the corporate responsibility to focus their efforts on both operational improvement programmes and sustainable initiatives in order to achieve better environmental protection, corporate reputation, quality management, cost performance and suppliers relations, as they are considered to be more important on organizational sustainability.  相似文献   
99.
In this paper, we develop a set‐theoretic and possible worlds approach to counterfactual analysis in case‐study explanation. Using this approach, we first consider four kinds of counterfactuals: necessary condition counterfactuals, SUIN condition counterfactuals, sufficient condition counterfactuals, and INUS condition counterfactuals. We explore the distinctive causal claims entailed in each, and conclude that necessary condition and SUIN condition counterfactuals are the most useful types for hypothesis assessment in case‐study research. We then turn attention to the development of a rigorous understanding of the ‘minimal‐rewrite’ rule, linking this rule to insights from set theory about the relative importance of necessary conditions. We show why, logically speaking, a comparative analysis of two necessary condition counterfactuals will tend to favour small events and contingent happenings. A third section then presents new tools for specifying the level of generality of the events in a counterfactual. We show why and how the goals of formulating empirically important versus empirically plausible counterfactuals stand in tension with one another. Finally, we use our framework to link counterfactual analysis to causal sequences, which in turn provides advantages for conducting counterfactual projections.  相似文献   
100.
Public-Private Partnership (PPP) is a new model of public management which consists of the contractual relationship between public and private entities. In particular, PPPs enable risk share between public and private sectors making the asymmetric information problem in a contractual arrangement more evident. The aim of this paper was to study a moral hazard problem applied to PPP contracts. To achieve this objective, a PPP computational contractual model including the moral hazard with lotteries was developed to assess how contractual changes could affect the optimum behavior of arrangement members. Simulations indicate that projects with higher economic value should attract more qualified firms, which may be why the companies expend more effort. To deal with possible contractual contingencies and try to minimize the moral hazard problem, the government could draw up more flexible contracts in order to include possible necessary changes and punish unwanted or improper consortium behavior.  相似文献   
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