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101.
Marriage and fertility in the United States have become less firmly entwined as more women bear children without marrying and more couples with children divorce. Today a sizeable number of children are expected to spend a portion of their childhood in one-parent households. Despite the trends in illegitimacy and divorce, the actual effect of out-of-wedlock childbearing on the living arrangements of children has not been fully explicated. Using the National Survey of Family Growth Cycle III, this paper estimates the probability that children aged 0–13 in 1982 are living in two-parent households, controlling for their mothers' marital statuses at their births. We find that marital status at birth is an important predictor of household structure at later ages for both white and black populations; however, the childhood environment is actually quite elastic as women marry, divorce, remarry, and redivorce. 相似文献
102.
RURAL POVERTY, URBAN POVERTY, AND PSYCHOLOGICAL WELL-BEING 总被引:1,自引:0,他引:1
Data from the National Survey of Families and Households are used to compare the psychological well-being of the rural and urban poor. Overall, the urban poor are higher in perceived health than the rural poor, although no differences are apparent in happiness or depression. Significant interactions are present between rural/urban poverty and sex, race, and family status. The psychological well-being of poor African Americans is higher in rural than urban areas, whereas the well-being of poor whites is higher in urban than rural areas. This trend is especially pronounced for depression among males. In addition, single men without children have especially high depression scores in rural areas, whereas married women without children have especially low depression scores in urban areas. The results are interpreted in terms of the environmental quality of inner-city neighborhoods and attitudes toward poverty in urban and rural communities. 相似文献
103.
The mean density of bacteria in a water body is commonly monitored using quantal assay. This paper describes the use of local scoring in estimating the spatial distribution of mean density from quantal assay results at a set of point locations. An application to estimating the mean density of fecal conform bacteria in a coastal pond is presented. Model diagnostics based on a parametric bootstrap are also presented. 相似文献
104.
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
105.
In this article we posit that racial discrimination is not uniform across the U.S. labor market. While it is likely that patterns of racial discrimination occur in some types of jobs more than others, little empirical research has examined the effect of race across segmented labor markets. Incorporating two decades of comparable General Social Survey data, this article revisits William J. Wilson's hypothesis that the significance of race in determining labor market outcomes is declining. We examine the effect of race within two dissimilar labor segments over time, dividing the labor market into technique‐versus social‐skills‐oriented segments. Using this theoretically useful dichotomy, we examine if the net effect of race (African American and white men) on occupational prestige has declined from the 1970s to the 1990s. Our multivariate analysis shows that the net effect of race is different in each labor market. This suggests that racial discrimination against African Americans is not uniform across the entire labor market, but instead is differentiately manifested within various labor market segments. Overall, our findings partially support Wilson's thesis indicating that while the effect of race is no longer a significant indicator of occupational prestige by the 1990s in a technique‐oriented job segment, it remains a significant predictive variable within a social‐skills‐oriented job segment, even when controlling for a range of social class and structural variables. 相似文献
106.
Barry R. Chiswick Yew Liang Lee Paul W. Miller 《The International migration review》2006,40(2):419-450
This article is concerned with the determinants of English language proficiency among immigrants in a longitudinal survey for Australia. It focuses on both visa category and variables derived from an economic model of the determinants of destination‐language proficiency among immigrants. Skills‐tested and economic immigrants have the greatest proficiency shortly after immigration, followed by family‐based visa recipients, with refugees having the lowest proficiency. Other variables the same, these differences disappear by 3.5 years after immigration for speaking skills; and although they diminish, they persist longer for reading and writing skills. The variables generated from the model of destination‐language proficiency (such as schooling and age at migration) are, in part, predictions of visa category, but they are more important statistically for explaining proficiency. 相似文献
107.
Walter R. Allen 《Sociological Forum》1995,10(4):569-592
Since 1965 hundreds of articles and books have been published about African American families. Nevertheless, our understanding of these families continues to be limited. There is a tendency to gloss over important within-group differences; thus, monolithic, stereotypic and inaccurance portrayals of Black family life are common. This paper sets aside debates of Black family pathology or viability, focusing instead on these families' essential character. The paper seeks to understand Black families on their own terms, locating them in relevant social, historical, political and cultural contexts. Key empirical patterns and trends reveal dramatic changes in Black family geographic location, headship, quality of life and socioeconomic status since 1950.A complex picture is revealed. There has been gradual but steady overall improvement alongside persistent, extreme racial disparties and pronounced class disparities among Black families. The proposed Black Family Socio-Ecological Context model specifies and connects institutional, interpersonal, environmental, temporal and cultural facts that shape the essential character of Black family life in such a way as to produce characteristics simultaneously shared and idiosyncratic. The model also provides an organized, systematic accounting of research and public policy issues relevant to the study of African American families.An early version co-authored with Richard A. English was presented during the National Council on Family Relations Meetings in Portland, Oregon, October 1980. 相似文献
108.
In this article, we describe a straightforward method for solving the probability of at least one malignant cell by time t, and the associated hazard function, in the general (i.e., nonhomogeneous) two-stage Moolgavkar-Venzon-Knudson (MVK) model of cancer. The method consists of solving four coupled ordinary differential equations derived from the Kolmogorov backward equations for this process. The relationship of this method to previously proposed solutions is discussed. 相似文献
109.
P. Battipaglia 《Statistical Methods and Applications》1996,5(2):179-202
Summary The evaluation of the performance of seasonal adjustment procedures is an issue of practical importance in view of the unobservable
nature of the components. Looking at just one indicator when judging the overall quality of a procedure may be misleading,
even though this is common practice when many series are involved.
The main purpose of this paper is to compare the information content of different synthetic indicators with reference to the
X-11-ARIMA procedure.
Sixty-six different types of monthly seasonal series are generated and the seasonal component then extracted by carrying out
X-11-ARIMA with standard options. The correlation between the pseudo-true error for each series and various synthetic indicators
allows us to compare the latter's reliability, under both the hypotheses of minimum and maximum variance of the pseudo-true
seasonal component.
We show that the overall quality indexQ-the indicator most commonly adopted by users of the X-11-ARIMA-is always outperformed by the simpler diagnostics based on
the stability of the estimates.
In particular, the “sliding-spans” indicator, proposed by Findley et al. (1990) and included in the diagnostics of the new
X-12 procedure, shows a much stronger correlation with the pseudo-true error in the seasonal adjustment.
We also show that the total forecasting errors in the one-year-ahead extrapolation of the seasonal component have a good informative
power and perform almost as well as the “sliding-spans” indicator. 相似文献
110.
Margarita Azmitia Catherine R. Cooper Eugene E. García Nora D. Dunbar 《Social Development》1996,5(1):1-23
This two-part study applied an ecocultural perspective to socialization of daily and long-term goals in low-income Mexican-American and European-American families with children in third, fifth, and seventh grades. The first part of the study examined family members' participation and parents' socialization goals and guidance strategies for their children's daily household chores and homework activities. The second part of the study examined parents' long-term aspirations and guidance strategies for their children's educational, vocational, and moral development. For daily activities, results showed that in Mexican-American families both parents and siblings played important roles, whereas in European-American families parents were the primary socialization agents. As predicted, in both groups parents' expertise influenced their guidance strategies. Finally, Mexican-American and European-American parents differed in their relative endorsement of gender, relational, and self-reliance goals for household chores. For long-term goals, parents in both groups held high educational, vocational, and moral aspirations for their children. However, some parents of seventh-graders had lower educational and vocational aspirations than those of fifth- and third-graders. Although expertise consistently influenced Mexican-American parents' guidance strategies, the pattern for European-American parents was mixed. The discussion highlights between- and within-group differences in daily and long-term socialization practices with an emphasis on resources and vulnerabilities in the families. 相似文献