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271.
Several countries have attempted to change human fertility through economic incentives. This paper presents simple mathematical models of the participation of couples in a locally funded program of economic incentives. The models take as a springboard China's one-child program. Localities with low per capita incentives attract few couples to the program, while localities with high incentives attract many couples at first, but the value of the benefits is then watered down. The models show that participation in the program may persistently oscillate or may decay to a stationary level. Which behavior occurs is determined by whether there are decreasing, constant, or increasing returns in the rates of participation in response to successive equal increments in the incentive offered, and by the extent to which prospective parents learn from experience with past oscillations in the incentives. The models raise many empirical questions about the dynamics of incentive programs.  相似文献   
272.
The author examines family structure in Santa Fe, the capital of New Granada, a Spanish colony that included Colombia, Ecuador, Panama, and Venezuela. The focus is on the late eighteenth and early nineteenth centuries. He finds that social class structure was closely related to ethnic group and skin color, and that the sex ratio was biased toward women. Women also headed nearly 50% of all households. Data are mainly from the 1801 smallpox census.  相似文献   
273.
Contemporary immigration to the United States and the formation of new ethnic groups are the complex and unintended social consequences of the expansion of the nation to its post-World War II position of global hegemony. Immigrant communities in the United States today are related to a history of American military, political, economic, and cultural involvement and intervention in the sending countries, especially in Asia and the Caribbean Basin, and to the linkages that are formed in the process that open a variety of legal and illegal migration pathways. The 19.8 million foreign-born persons counted in the 1990 U.S. census formed the largest immigrant population in the world, though in relative terms, only 7.9% of the U.S. population was foreign-born, a lower proportion than earlier in this century. Today's immigrants are extraordinarily diverse, a reflection of polar-opposite types of migrations embedded in very different historical and structural contexts. Also, unlike the expanding economy that absorbed earlier flows from Europe, since the 1970s new immigrants have entered an hourglass economy with reduced opportunities for social mobility, particularly among the less educated, and new waves of refugees have entered a welfare state with expanded opportunities for public assistance. This paper seeks to make sense of the new diversity. A typology of contemporary immigrants is presented, and their patterns of settlement, their distinctive social and economic characteristics compared to major native-born racial-ethnic groups, and their different modes of incorporation in—and consequences for—American society are considered.  相似文献   
274.
In October 1992, the American College of Physician Executives sponsored a study tour to Berlin, Germany, and Amsterdam, Holland. Meetings were held with government officials, third-party payers, and providers, and on-site visits were made at hospitals, clinics, and academic centers. The purpose was to study the health care delivery system in those countries and to share some insights with the countries' hosts on the U.S. system. In a series of reports that began in the July issue of the journal, 5 of the 10 study tour participants describe their impressions of the tour and of the health care systems in the countries that were visited. In this final report, the implications of the German and Dutch systems for reform of the U.S. health care system are discussed.  相似文献   
275.
"This study addressed the problem of the Moroccan immigration into Spain within the context of South-North movements, focusing on analyzing provisional data from the last immigrant regularization in the country completed during the end months of 1991."  相似文献   
276.
277.
Responses to the Adult Career Concerns Inventory (ACCI: Super, Thompson, Lindeman, Myers, & Jordaan, 1988) were organized through cluster analysis to identify different ways in which adults use exploratory behavior to cope with career development tasks. Significant differences in life-role salience among the types of adult career explorers identified were also investigated. Findings indicated a variety of ways in which adults use exploratory behavior. However, no significant differences were found in life-role salience among the types of career explorers. The discussion explains how career counselors can interpret their clients' ACCI profiles to select appropriate career interventions.  相似文献   
278.
Immigration has long been a national and state concern. The 1989 Legalized Population Survey (LPS-1) collected data on illegal immigrants to the US who subsequently became legalized aliens under the provisions of the 1986 Immigration Reform and Control Act. These data are used in a study assessing whether undocumented male and female immigrants improve their earnings and occupational status over time and the extent of variation in occupational status and mobility by gender and region. The data indicate that both undocumented men and women, on average, improved their earnings and occupational status between their first jobs in the US and their jobs just before applying for legalization under the 1986 Immigration Reform and Control Act. However, the earnings, occupational status, and occupational mobility of men were greater than for women.  相似文献   
279.
280.
LetX1,X2, ..., be real-valued random variables forming a strictly stationary sequence, and satisfying the basic requirement of being either pairwise positively quadrant dependent or pairwise negatively quadrant dependent. LetF^ be the marginal distribution function of theXips, which is estimated by the empirical distribution functionFn and also by a smooth kernel-type estimateFn, by means of the segmentX1, ...,Xn. These estimates are compared on the basis of their mean squared errors (MSE). The main results of this paper are the following. Under certain regularity conditions, the optimal bandwidth (in the MSE sense) is determined, and is found to be the same as that in the independent identically distributed case. It is also shown thatn MSE(Fn(t)) andnMSE (F^n(t)) tend to the same constant, asn→∞ so that one can not discriminate be tween the two estimates on the basis of the MSE. Next, ifi(n) = min {k∈{1, 2, ...}; MSE (Fk(t)) ≤ MSE (Fn(t))}, then it is proved thati(n)/n tends to 1, asn→∞. Thus, once again, one can not choose one estimate over the other in terms of their asymptotic relative efficiency. If, however, the squared bias ofF^n(t) tends to 0 sufficiently fast, or equivalently, the bandwidthhn satisfies the requirement thatnh3n→ 0, asn→∞, it is shown that, for a suitable choice of the kernel, (i(n) ?n)/(nhn) tends to a positive number, asn→∞ It follows that the deficiency ofFn(t) with respect toF^n(t),i(n) ?n, is substantial, and, actually, tends to ∞, asn→∞. In terms of deficiency, the smooth estimateF^n(t) is preferable to the empirical distribution functionFn(t)  相似文献   
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