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991.
992.
We study the impact of emissions tax and emissions cap‐and‐trade regulation on a firm's technology choice and capacity decisions. We show that emissions price uncertainty under cap‐and‐trade results in greater expected profit than a constant emissions price under an emissions tax, which contradicts popular arguments that the greater uncertainty under cap‐and‐trade will erode value. We further show that two operational drivers underlie this result: (i) the firm's option not to operate, which effectively right‐censors the uncertain emissions price; and (ii) dispatch flexibility, which is the firm's ability to first deploy its most profitable capacity given the realized emissions price. In addition to these managerial insights, we also explore policy implications: the effect of emissions price level, and the effect of investment and production subsidies. Through an illustrative example, we show that production subsidies of higher investment and production cost technologies (such as carbon capture and storage technologies) have no effect on the firm's optimal total capacity when firms own a portfolio of both clean and dirty technologies, but that investment subsidies of these technologies increase the firm's total capacity, conditionally increasing expected emissions. A subsidy of a lower production cost technology, on the other hand, has no effect on the firm's optimal total capacity in multi‐technology portfolios, regardless of whether the subsidy is a production or investment subsidy.  相似文献   
993.
In this paper, we initiate the study of total liar’s domination of a graph. A subset L?V of a graph G=(V,E) is called a total liar’s dominating set of G if (i) for all vV, |N G (v)∩L|≥2 and (ii) for every pair u,vV of distinct vertices, |(N G (u)∪N G (v))∩L|≥3. The total liar’s domination number of a graph G is the cardinality of a minimum total liar’s dominating set of G and is denoted by γ TLR (G). The Minimum Total Liar’s Domination Problem is to find a total liar’s dominating set of minimum cardinality of the input graph G. Given a graph G and a positive integer k, the Total Liar’s Domination Decision Problem is to check whether G has a total liar’s dominating set of cardinality at most k. In this paper, we give a necessary and sufficient condition for the existence of a total liar’s dominating set in a graph. We show that the Total Liar’s Domination Decision Problem is NP-complete for general graphs and is NP-complete even for split graphs and hence for chordal graphs. We also propose a 2(lnΔ(G)+1)-approximation algorithm for the Minimum Total Liar’s Domination Problem, where Δ(G) is the maximum degree of the input graph G. We show that Minimum Total Liar’s Domination Problem cannot be approximated within a factor of $(\frac{1}{8}-\epsilon)\ln(|V|)$ for any ?>0, unless NP?DTIME(|V|loglog|V|). Finally, we show that Minimum Total Liar’s Domination Problem is APX-complete for graphs with bounded degree 4.  相似文献   
994.
We examine whether family firms undertake value creating high technology M&A. We also examine whether level of ownership, diversification, agency issues and CEO type matter. Our sample consists of high-technology M&A undertaken by Canadian firms over the period 1997–2006. Canada offers a setting with many family firms and the use of control enhancing mechanisms such as dual class shares and pyramid structures. We find a positive relationship between family ownership and announcement period abnormal returns. This relationship, however, starts to decrease at higher levels of ownership but remains overall positive. We also show that the agency conflict between shareholders and professional managers has a detrimental impact on announcement period abnormal returns whereas the conflict between controlling and minority shareholders via control enhancing mechanisms does not. Finally, we document that founder CEO undertake better high tech M&A than descendant or hired CEO.  相似文献   
995.

Does audio computer-assisted self-interviewing (ACASI) produce more valid reporting of sexual activity and related behaviors than face-to-face interviews or self-administered interviews? This analysis, based on data collected from over 6,000 unmarried adolescents in two districts of Kenya—Nyeri and Kisumu—indicates substantial and significant differences in reported rates of premarital sex across interview modes, although not always in the expected direction. Our assumption that girls underreport sexual activity in face-to-face interviews by comparison with ACASI is not confirmed by the Nyeri data, but our results from Kisumu are considerably more promising. As for boys, who we believe exaggerate their level of sexual activity in face-to-face interviews, a more nuanced set of expectations regarding the reporting of sensitive behaviors was offered; our results from Kisumu, although not always significant, by and large conform to expectations.

  相似文献   
996.
Using data from a 1966–1967 probability sample of West Malaysian married women 15–44 years of age, this paper analyzes the characteristics of women who were active in diffusing information about family planning. The woman’s age and her parity, her educational attainment, her race, her present residence (urban-rural), and whether or not she wanted more children were significantly related to opinion leadership in bivariate tables. However, these relationships appeared to be substantial mainly because these social and demographic characteristics were highly related to whether the woman participated in discussions about family planning with other women. Among women who did participate in such discussions, the social and demographic variables were not substantially related to opinion leadership. In fact, the critical variables for opinion leadership appeared to be participation in the discussions, greater knowledge of family planning, and a higher level of family planning use. An attempt is also made to assess the effect of interpersonal communication on the adoption of family planning among women in the sample.  相似文献   
997.
Demography as a Spatial Social Science   总被引:1,自引:0,他引:1  
Scholars in many social science disciplines have taken note of the re-emerging interest in issues concerning social processes embedded within a spatial context. While some argue that this awakening is refreshing and new and, in fact, long overdue, I demonstrate that spatially focused demographic theories and research agendas clearly predate contemporary interest in these topics. I assert that recent methodological advancements have merely encouraged and brought refinement to the expanding body of spatially oriented population research—research strongly rooted in demographic tradition and practice. Indeed, I make the claim that, until roughly the mid-20th century, virtually all demography in the United States (and elsewhere, but not specifically examined here) was spatial demography. Then, shortly after mid-century, a paradigm shift occurred, and the scientific study of population quickly came to be dominated by attention to the individual as the agent of demographic action. Traditional spatial demography—macro-demography—gave way to micro-demography, and, I argue, most demographers simply abandoned the data and approach of spatial demography. In closing the paper I include a brief discussion of the recent awakening that has come to spatial demographers from developments in other disciplines, principally geography, regional science, and spatial econometrics.  相似文献   
998.
This research examined whether a parent's non-disclosure of his or her homosexual or bisexual orientation within the family unit negatively affects self-esteem and anxiety in children, as measured in adulthood. Thirty-six subjects indicated that they had not known of their parent's sexual orientation until an average age of sixteen for the children of lesbian or bisexual mothers, and twenty-two for the children of gay or bisexual fathers. This group's scores on the Rosenberg Self-Esteem Scale, the Marlowe Crowne Social Desirabilty Scale and the State-Trait Anxiety Scale were compared to scores obtained by sixty-three participants who did not have a homosexual/bisexual parent. The number of years a secretive environment surrounded the child was measured, as were participants' attitudes about the secret sexual identity. Although the study did not find that adults previously raised with a closeted parent had significantly higher levels of anxiety or lower levels of self-esteem, results indicated that those who had been raised as children with non-disclosed lesbian mothers showed a significantly higher level of self-esteem than participants with heterosexual parents. Implications of the findings for the targeted population are discussed.  相似文献   
999.
Demographic and social factors affecting infant mortality in rural northern Thailand are examined using log-linear modifiedmultiple regression models and data drawn from a representative sample of married couples in Chiang Mai and Chiang Rai provinces. Demographic factors do not account for the effects of variations in parental ability or willingness to provide adequate infant care. The final model estimated incorporated both these social dimensions of child care. Parental ability, measured by father’s social class, mother’s health information, and local community development levels, continued to have significant independent effects upon infant survival. Parental willingness, measured by parent’s beliefs about intergenerational wealth transfers, no longer had a significant effect net of other social variables, but infant survival was still affected by whether both parents wanted a birth.  相似文献   
1000.
Using Thai data, this paper develops and tests a model of rural-urban mobility behavior in a context dominated by high levels of circular rural-urban mobility. With mobility plans and mobility behavior measured in analogous ways, a close correspondence between mobility plans and mobility behavior is found. In spite of this close correspondence, however, multivariate analysis shows that past mobility behavior—rather than mobility plans—is the most important predictor of subsequent mobility. Where experience with a given type of behavior is abundant, prior behavior may often be the best predictor of subsequent behavior, but where experience with a given type of behavior is scarce, behavioral intentions may be a more relevant explanatory variable.The research reported here was funded by the Rockefeller and Ford Foundations' Research Program on Population and Development Policy (RF 77065; Allocation 164). An earlier version of this paper was presented at the section on migration strategies, migration intentions, and migration decisions at the annual meeting of the Population Association of America, Minneapolis, Minnesota, May 3–5, 1984.  相似文献   
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