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991.
992.
Let X
1, X
2,... be iid random variables (rv's) with the support on nonnegative integers and let (W
n
, n≥0) denote the corresponding sequence of weak record values. We obtain new characterization of geometric and some other discrete
distributions based on different forms of partial independence of rv's W
n
and W
n+r
—W
n
for some fixed n≥0 and r≥1. We also prove that rv's W
0 and W
n+1
—W
n
have identical distribution if and only if (iff) the underlying distribution is geometric. 相似文献
993.
Barry T. Hirsch 《Journal of Labor Research》2004,25(2):233-266
I examine evidence on private sector union wage gaps in the United States. The consensus opinion among labor economists of
an average union premium of roughly 15 percent is called into question. Two forms of measurement error bias downward standard
wage gap estimates. Match bias results from Census earnings imputation procedures that do not include union status as a match
criterion. Downward bias is roughly equal to the proportion of workers with imputed earnings, currently about 30 percent.
Misclassification of union status causes additional attenuation in union gap measures. This bias has worsened as private sector
density has declined, since an increasing proportion of workers designated as union are instead nonunion workers. Corrections
for misclassification and match bias lead to estimated union gaps substantially higher than standard estimates, but with less
of a downward trend since the mid 1980s. Private sector union gaps corrected for these biases are estimated from the CPS for
1973–2001. The uncorrected estimate for 2001 is .13 log points. Correction for match bias increases the gap to .18 log points;
further correction for misclassification bias, based on an assumed 2 percent error rate, increases the gap to .24. Reexamination
of the skill-upgrading hypothesis leads to the conclusion that higher union gap estimates are plausible. The conventional
wisdom of a 15 percent union wage premium warrants reexamination. 相似文献
994.
Janis B. Feldman 《Child and Adolescent Social Work Journal》2007,24(3):209-234
This study was designed to determine the significant variables predicting prenatal attachment in an adolescent population.
Scientifically supported knowledge of the factors enhancing attachment plays a crucial role in assisting social workers and
other health care professionals to accurately assess and intervene to decrease pregnancy risks. Previous prenatal attachment
studies demonstrated conflicting findings due to problems from using different theoretical frameworks and research methodologies.
In order to ensure consistency, this study infused an attachment theory perspective. Bowlby’s attachment theory, Levitt’s
support expectations model, and research from prenatal relationship studies were integrated. The social survey sampled 129
minority status pregnant adolescents attending public school. Measurements included the Prenatal Attachment Inventory (PAI) and the Support Expectations Index (SEI). Regression analyses revealed that support expectation was a powerful predictor of prenatal attachment with pregnancy planning
and less stress adding importantly to explain over 33% of the variance. Support expectation was a greater predictor of prenatal
attachment than the actual support available. Findings also supported the construct of prenatal attachment as the initial
stage of development of the life cycle.
Janis B. Feldman is an Assistant Professor, University, of Texas-Pan American. 相似文献
995.
Sandra Krapf Katharina Wolf 《KZfSS K?lner Zeitschrift für Soziologie und Sozialpsychologie》2015,67(1):137-164
In this study, we use data of the German Mikrozensus to explore first and second birth behavior of migrants’ descendants. Whereas prior waves of the Mikrozensus only included respondents’ citizenship, in the survey years 2005 and 2009 also parental citizenship has been surveyed. This allows us to identify respondents’ migrant backgrounds, even if they have German citizenship. We distinguish those who migrated as children (1.5 generation) from those who were born to Turkish parents in Germany (second generation migrants). We compare both migrant generations to German non-migrants. Using discrete-time hazard models, our results show that 1.5 generation migrants have the highest probability of having a first and second birth, while German non-migrants have the lowest birth probabilities. The second generation lies in-between. This pattern also persists after taking the educational attainment of respondents into consideration. However, there seems to be an adaptation of highly educated second generation Turkish migrants to non-migrant Germans: we find no significant differences in the probability of having a first birth in the two groups. For second births, we do not find this pattern which might be related to the young age structure in the sample of second generation migrants. 相似文献
996.
In a mixture experiment, the response depends on the proportions of the mixing components. Canonical models of different degrees and also other models have been suggested to represent the mean response. Optimum designs for estimation of the parameters of the models have been investigated by different authors. In most cases, the optimum design includes the vertex points of the simplex as support points of the design, which are not mixture combinations in the true non-trivial sense. In this paper, optimum designs have been obtained when the experimental region is an ellipsoidal subspace of the entire factor space which does not cover the vertex points of the simplex. 相似文献
997.
Eliciting decision weights by adapting de Finetti’s betting-odds method to prospect theory 总被引:1,自引:0,他引:1
Enrico Diecidue Peter P. Wakker Marcel Zeelenberg 《Journal of Risk and Uncertainty》2007,34(3):179-199
This paper extends de Finetti’s betting-odds method for assessing subjective beliefs to ambiguous events. Thus, a tractable
manner for measuring decision weights under ambiguity is obtained. De Finetti’s method is so transparent that decision makers
can evaluate the relevant tradeoffs in complex situations. The resulting data can easily be analyzed, using nonparametric
techniques. Our extension is implemented in an experiment on predicting next-day’s performance of the Dow Jones and Nikkei
stock indexes, where we test the existence and nature of rank dependence, finding usual patterns. We also find violations
of rank dependence.
相似文献
Peter P. WakkerEmail: URL: http://www.few.eur.nl/few/people/wakker/ |
998.
We present a unified look at myopic stability concepts for hedonic games, and discuss the status of the existence problems
of stable coalition structures. In particular, we show that contractual strictly core stable coalition structures always exist,
and present a sufficient condition for the existence of contractually Nash stable coalition structures on the class of separable
games.
We gratefully acknowledge financial support from the Alexander von Humboldt Foundation (D. Dimitrov)“by “D. Dimitrov gratefully
acknowledges financial support from the Alexander von Humboldt Foundation. 相似文献
999.
Christian Gollier 《Journal of Risk and Uncertainty》2007,35(2):107-127
We examine the collective risk attitude of a group with heterogeneous beliefs. We prove that the wealth-dependent probability
distribution used by the representative agent is biased in favor of the beliefs of the more risk tolerant consumers. Moreover,
increasing disagreement on the state probability raises the state probability of the representative agent. It implies that
when most disagreements are concentrated in the tails of the distribution, the perceived collective risk is magnified. This
can help to solve the equity premium puzzle. We show that the trade volume and the equity premium are positively correlated.
相似文献
Christian GollierEmail: |
1000.
Matthew E. Kahn 《Journal of Risk and Uncertainty》2007,35(1):17-43
Unexpected events such as environmental catastrophes capture wide public attention. Soon after five major shocks—Three Mile
Island, Love Canal, Bhopal, Chernobyl, and the Exxon Valdez oil spill—Congress voted on new risk regulation. This paper conducts
an event study to test whether individual congressional representatives were “shocked” by these environmental disasters into
increasing their probability of voting in favor of risk legislation. On average, representatives were less likely to vote
in favor of bills tied to these five events. Significant heterogeneity in representatives’ responses to these shocks is documented.
Liberal Northeast representatives were most likely to increase their pro-environment voting in the aftermath of these shocks.
相似文献
Matthew E. KahnEmail: |