全文获取类型
收费全文 | 8891篇 |
免费 | 301篇 |
专业分类
管理学 | 1483篇 |
民族学 | 76篇 |
人才学 | 2篇 |
人口学 | 747篇 |
丛书文集 | 53篇 |
理论方法论 | 979篇 |
综合类 | 89篇 |
社会学 | 4579篇 |
统计学 | 1184篇 |
出版年
2023年 | 66篇 |
2021年 | 57篇 |
2020年 | 159篇 |
2019年 | 244篇 |
2018年 | 230篇 |
2017年 | 325篇 |
2016年 | 251篇 |
2015年 | 228篇 |
2014年 | 236篇 |
2013年 | 1557篇 |
2012年 | 305篇 |
2011年 | 363篇 |
2010年 | 263篇 |
2009年 | 224篇 |
2008年 | 271篇 |
2007年 | 307篇 |
2006年 | 253篇 |
2005年 | 252篇 |
2004年 | 253篇 |
2003年 | 218篇 |
2002年 | 264篇 |
2001年 | 207篇 |
2000年 | 179篇 |
1999年 | 159篇 |
1998年 | 125篇 |
1997年 | 129篇 |
1996年 | 101篇 |
1995年 | 117篇 |
1994年 | 96篇 |
1993年 | 112篇 |
1992年 | 98篇 |
1991年 | 102篇 |
1990年 | 95篇 |
1989年 | 94篇 |
1988年 | 111篇 |
1987年 | 96篇 |
1986年 | 69篇 |
1985年 | 69篇 |
1984年 | 97篇 |
1983年 | 97篇 |
1982年 | 75篇 |
1981年 | 74篇 |
1980年 | 67篇 |
1979年 | 71篇 |
1978年 | 67篇 |
1977年 | 49篇 |
1976年 | 55篇 |
1975年 | 48篇 |
1974年 | 34篇 |
1972年 | 30篇 |
排序方式: 共有9192条查询结果,搜索用时 31 毫秒
91.
92.
Violations of dominance in pricing judgments 总被引:1,自引:1,他引:0
The dominance principle states that the judged price of gamble A should be equal to or greater than the judged price of gamble B whenever A's outcomes are equal to or better than the corresponding outcomes of B, holding everything else constant. Subjects often violate the dominance principle by assigning a higher price to a gamble with some probability of winning a positive amount, Y, otherwise zero, than to a superior gamble with the same chances of winning Y, otherwise winning X. Violations also occur with losses. Results are consistent with a configural-weight theory in which the decision weight for each outcome depends on the rank of the outcome with respect to the other outcomes in the lottery and the value of the outcome (zero vs. nonzero).The authors thank Shi-jie Chang, Duncan Luce, and Lisa Ordóñez for comments on an earlier draft. This research was supported by a National Science Foundation grant to the first author (BNS-8451368). Requests for reprints should be sent to Barbara Mellers, Dept. of Psychology, University of California, Berkeley, CA 94720. 相似文献
93.
The problem of determining the number of multi-type protection devices and their locations on electrical supply tree networks with subtree dependency is investigated. The aim is to reduce the amount of inconvenience caused to customers that are affected by any given fault on the networks. An appropriate implementation of tabu search is proposed. We exploit a variable neighborhood and a soft aspiration level, and we embed a data structure and reduction tests into the search to speed up the process. Computational tests are performed on randomly generated electrical tree networks varying in size and branch complexity with encouraging results. 相似文献
94.
Michael Weba 《Statistical Papers》2002,43(3):445-452
n possibly different success probabilities p
1, p
2, ..., p
n
is frequently approximated by a Poisson distribution with parameter λ = p
1 + p
2 + ... + p
n
. LeCam's bound p
2
1 + p
2
2 + ... + p
n
2 for the total variation distance between both distributions is particularly useful provided the success probabilities are
small.
The paper presents an improved version of LeCam's bound if a generalized d-dimensional Poisson binomial distribution is to be approximated by a compound Poisson distribution.
Received: May 10, 2000; revised version: January 15, 2001 相似文献
95.
96.
The skin is a route of exposure that needs to be considered when conducting a risk assessment. It is necessary to identify the potential for dermal penetration by a chemical as well as to determine the overall importance of the dermal route of exposure as compared with inhalation or oral routes of exposure. The physical state of the chemical, vapor or liquid, the concentration, neat or dilute, and the vehicle, lipid or aqueous, is also important. Dermal risk is related to the product of the amounts of penetration and toxicity. Toxicity involves local effects on the skin itself and the potential for systemic effects. Dermal penetration is described in large part by the permeability constant. When permeability constants are not known, partition coefficients can be used to estimate a chemical's potential to permeate the skin. With these concepts in mind, a tiered approach is proposed for dermal risk assessment. A key first step is the determination of a skin-to-air or skin-to-medium partition coefficient to estimate a potential for dermal absorption. Building a physiologically-based pharmacokinetic (PBPK) model is another step in the tiered approach and is useful prior to classical in vivo toxicity tests. A PBPK model can be used to determine a permeability constant for a chemical as well as to show the distribution of the chemical systemically. A detailed understanding of species differences in the structure and function of the skin and how they relate to differences in penetration rates is necessary in order to extrapolate animal data from PBPK models to the human. A study is in progress to examine anatomical differences for four species. 相似文献
97.
James A. Yunker 《Economic inquiry》1994,32(4):597-615
A small-scale general equilibrium model in which the distribution of capital wealth is a key parameter is employed to examine the potential economic consequences of greater capital wealth equality. Every performance indicator examined – aggregate income, consumption equality, social welfare in the sum-of-utilities sense, and aggregate saving –is improved by greater capital wealth equality. However, the bottom-line social welfare gain, relative to the present high-inequality situation – even from the maximum achievable level of complete equality in capital wealth distribution – would be numerically rather modest. 相似文献
98.
Are the decisions of American policymakers informed by generaltrends in the publics ideology or by the publicspolicy-specific preferences? In this article we discuss twoexplanations for the types of public opinion information thatpoliticians collect and use. Using a unique data set of privatepolls from the White House of Richard Nixon, we find that whenopinion data on specific policies were available, the presidentrelied on them and not on general ideology data. On less importantissues, however, we find that the president often chose notto collect policy-specific data and instead relied on generalideology data. The differential collection and use of informationby policymakers reflect varying strategic calculations. Theyalso have profound implications for representative democracyand the demands placed on citizens and governors. 相似文献
99.
100.
Noah Lewin‐Epstein Haya Stier Michael Braun 《Journal of marriage and the family》2006,68(5):1147-1164
We compare the patterns of household division of labor in Germany and Israel—two countries that share key elements of the corporatist welfare regime but differ in their gender regimes—and evaluate several hypotheses using data from the 2002 International Social Survey Program. Although time constraints and relative resources affect the division of household labor and women’s housework in both societies, we find that in Germany the gender order of household labor is more rigid, whereas in Israel the spouses’ linked labor market status exerts distinctive effects. We also find significant relationships between gender ideology and the division of household labor. We discuss the theoretical advantages of approaching the comparative study of gender inequality from the vantage point of family and gender regimes. 相似文献