全文获取类型
收费全文 | 32095篇 |
免费 | 702篇 |
国内免费 | 1篇 |
专业分类
管理学 | 4512篇 |
民族学 | 219篇 |
人才学 | 4篇 |
人口学 | 4123篇 |
丛书文集 | 92篇 |
教育普及 | 1篇 |
理论方法论 | 2541篇 |
综合类 | 477篇 |
社会学 | 15425篇 |
统计学 | 5404篇 |
出版年
2023年 | 151篇 |
2022年 | 93篇 |
2021年 | 147篇 |
2020年 | 399篇 |
2019年 | 599篇 |
2018年 | 2229篇 |
2017年 | 2438篇 |
2016年 | 1666篇 |
2015年 | 513篇 |
2014年 | 682篇 |
2013年 | 4007篇 |
2012年 | 1129篇 |
2011年 | 1808篇 |
2010年 | 1560篇 |
2009年 | 1233篇 |
2008年 | 1388篇 |
2007年 | 1509篇 |
2006年 | 614篇 |
2005年 | 730篇 |
2004年 | 733篇 |
2003年 | 639篇 |
2002年 | 535篇 |
2001年 | 539篇 |
2000年 | 471篇 |
1999年 | 466篇 |
1998年 | 358篇 |
1997年 | 293篇 |
1996年 | 334篇 |
1995年 | 314篇 |
1994年 | 291篇 |
1993年 | 297篇 |
1992年 | 337篇 |
1991年 | 339篇 |
1990年 | 325篇 |
1989年 | 285篇 |
1988年 | 282篇 |
1987年 | 233篇 |
1986年 | 253篇 |
1985年 | 290篇 |
1984年 | 253篇 |
1983年 | 217篇 |
1982年 | 188篇 |
1981年 | 150篇 |
1980年 | 167篇 |
1979年 | 185篇 |
1978年 | 149篇 |
1977年 | 130篇 |
1976年 | 102篇 |
1975年 | 104篇 |
1974年 | 109篇 |
排序方式: 共有10000条查询结果,搜索用时 187 毫秒
911.
This paper proposes a functional connectivity approach, inspired by brain imaging literature, to model cross-sectional dependence.
Using a varying parameter framework, the model allows correlation patterns to arise from complex economic or social relations
rather than being simply functions of economic or geographic distances between locations. It nests the conventional spatial
and factor model approaches as special cases. A Bayesian Markov Chain Monte Carlo method implements this approach. A small
scale Monte Carlo study is conducted to evaluate the performance of this approach in finite samples, which outperforms both
a spatial model and a factor model. We apply the functional connectivity approach to estimate a hedonic housing price model
for Paris using housing transactions over the period 1990–2003. It allows us to get more information about complex spatial
connections and appears more suitable to capture the cross-sectional dependence than the conventional methods. 相似文献
912.
We describe a first experiment on whether product complexity affects competition and consumers in retail markets. We are unable
to detect a significant effect of product complexity on prices, except insofar as the demand elasticity for complex products
is higher. However, there is qualified evidence that complex products have the potential to induce consumers to buy more than
they would otherwise. In this sense, consumer exploitability in quantities cannot be ruled out. We also find evidence for
shaping effects: consumers’ preferences are shaped by past experience with prices, and firms may in principle exploit this
to sell more. 相似文献
913.
A Diamond-Stiglitz approach to the demand for self-protection 总被引:1,自引:0,他引:1
The existing research concerning the relationship between risk aversion and prudence and the demand for self-protection assumes
that the loss variable follows a Bernoulli distribution, and that changes in the level of self-protection are mean preserving.
The analysis here replaces these two very strong conditions with ones which are more general. When doing this, the method
of analysis is also significantly modified. This modification includes representing a change in the level of self-protection
using the procedure developed by Diamond and Stiglitz (Journal of Economic Theory 8:337-360, 1974) for representing a change in risk. This alternate representation allows the existing findings to be generalized considerably,
and also simplifies the analysis. 相似文献
914.
Despite the fact that sickle-cell disease (SCD) is perhaps the most “racialized” medical condition in the USA, very little is known about how “race” impacts public support for health policies related to the condition. We embedded an experiment within the 2011 Cooperative Congressional Election Study in order to assess perceptions about SCD among 1250 participants from diverse backgrounds and evaluate the extent to which these perceptions were associated with support for government spending on SCD-related benefits. We manipulated the racial phenotype of SCD advocates who requested additional government funding and asked participants to indicate how much the government should provide. Overall, participants expressed moderately positive attitudes about SCD, and there were no differences in funding support based on the race of the advocate. However, white participants supported less funding compared to nonwhite participants, even after adjusting for a number of demographic and attitudinal covariates. These findings suggest that a complex relationship between racial identification and implicit racism may shape public perceptions about SCD that negatively influences perceivers’ support for SCD-related policy. 相似文献
915.
Robert?Joseph?TaylorEmail authorView authors OrcID profile Dawne?M.?Mouzon Ann?W.?Nguyen Linda?M.?Chatters 《Race and social problems》2016,8(4):326-339
This study examined reciprocal support networks involving extended family, friends and church members among African Americans. Our analysis examined specific patterns of reciprocal support (i.e., received only, gave only, both gave and received, neither gave or received), as well as network characteristics (i.e., contact and subjective closeness) as correlates of reciprocal support. The analysis is based on the African American subsample of the National Survey of American Life. Overall, our findings indicate that African Americans are very involved in reciprocal support networks with their extended family, friends and church members. Respondents were most extensively involved in reciprocal supports with extended family members, followed closely by friends and church networks. Network characteristics (i.e., contact and subjective closeness) were significantly and consistently associated with involvement with reciprocal support exchanges for all three networks. These and other findings are discussed in detail. This study complements previous work on the complementary roles of family, friend and congregational support networks, as well as studies of racial differences in informal support networks. 相似文献
916.
Sheretta T. Butler-Barnes Stephanie Cook Seanna Leath Cleopatra Caldwell 《Race and social problems》2018,10(1):30-41
This study explored the extent to which private regard and religiosity beliefs serve as protective factors for school bonding among African American and Caribbean black adolescents who experience racial discrimination in school. Findings are drawn from a nationally representative sample of (n = 810) African American and (n = 360) Caribbean black adolescents (52% girls) aged 13–17 (Mage = 15, SD = 1.42) years. Results suggest that perceiving racial discrimination from teachers was associated with lower levels of school bonding for African American and Caribbean black adolescents. For African American adolescents, perceiving more racial discrimination from teachers and reporting lower private regard beliefs was associated with less school bonding. The findings for Caribbean black adolescents revealed that endorsing moderate levels of religiosity and perceiving higher rates of teacher discrimination was associated with less school bonding. The developmental significance and implications for future research are discussed. 相似文献
917.
ABSTRACT For African American women, hair is a key site of identity formation and self-esteem that has been largely ignored by education researchers. Fifty-six African American women shared memories of negative hair experiences in school as a means to magnify the implicit injuries of racial and gender marginalization in educational environments. Memories consisted of hair shaming and suffering the consequences of hair damage, by way of classmate or teacher. Embarrassment and anxiety were the most frequently reported emotional reaction, resulting in participants’ discomfort in school and in their interpersonal relationships. Findings from this study suggest that hair bias represents a source of trauma and identity negotiation within school contexts. Critical Black feminist theories were used to frame the method and interpretation of participants’ reflective narratives. The insights provided through the narrative sample fuel recommendations regarding anti-bias teaching and school policy reform. 相似文献
918.
This paper studies the dynamics of long‐term contracts in repeated principal–agent relationships with an impatient agent. Despite the absence of exogenous uncertainty, Pareto‐optimal dynamic contracts generically oscillate between favoring the principal and favoring the agent. 相似文献
919.
Ayse Kocabiyikoglu Celile Itir Gogus M. Sinan Gonul 《Production and Operations Management》2015,24(5):750-761
We study and compare decision‐making behavior under the newsvendor and the two‐class revenue management models, in an experimental setting. We observe that, under both problems, decision makers deviate significantly from normative benchmarks. Furthermore, revenue management decisions are consistently higher compared to the newsvendor order quantities. In the face of increasing demand variability, revenue managers increase allocations; this behavior is consistent with normative patterns when the ratio of the selling prices of the two customer segments is less than 1/2, but is its exact opposite when this ratio is greater than 1/2. Newsvendors' behavior with respect to changing demand variability, on the other hand, is consistent with normative trends. We also observe that losses due to leftovers weigh more in newsvendor decisions compared to the revenue management model; we argue that overage cost is more salient in the newsvendor problem because it is perceived as a direct loss, and propose this as the driver of the differences in behavior observed under the two problems. 相似文献
920.
We measure the relative ideological positions of newspapers, voters, interest groups, and political parties, using data on ballot propositions. We exploit the fact that newspapers, parties, and interest groups take positions on these propositions, and the fact that citizens ultimately vote on them. We find that, on average, newspapers in the United States are located almost exactly at the median voter in their states—that is, they are balanced around the median voter. Still, there is a significant amount of ideological heterogeneity across newspapers, which is smaller than the one found for interest groups. However, when we group propositions by issue area, we find a sizable amount of ideological imbalance: broadly speaking, newspapers are to the left of the state‐level median voter on many social issues, and to the right on many economic issues. To complete the picture, we use two existing methods of measuring bias and show that the news and editorial sections of newspapers have almost identical partisan positions. 相似文献