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91.
In this paper we incorporate a linear demand function to model the price-volume causal relationship into stochastic cost-volume-profit (CVP) analysis. We assume that the objective function is to maximize expected profit; other objective functions are also discussed and compared. A linear stochastic model follows from which probabilistic statements can be easily obtained if the random variables are assumed to be multivariate normal. The basic framework is shown to be a special case of project value maximization where project value is the cash flow of the project discounted for time and risk according to the capital asset pricing model. Moreover, an intertemporal extension that considers inventory is developed. In summary, a new approach to stochastic CVP analysis that incorporates the management decision process in an uncertain environment is developed. 相似文献
92.
Using the first (1995) and third (2001-2002) waves of the Add Health survey, we examine women 's family transitions up to age 24. Only a third of all women marry, and a fifth of those marriages dissolve before age 24. Three out of eight women have afirst birth, with a substantial majority of those births outside of marriage: 66% for whites, 96% for blacks, and 72% for Mexican Americans. Cohabitation is the predominant union form; 59% of women cohabit at least once by age 24. Most cohabitations are short lived, with approximately one in five resulting in a marriage. We summarize the family and relationship experience of women up to age 24 in terms offour categories, each accounting for roughly a quarter of all women. Category 1 has the women who remain single nonparents. Category 2 has the early marriers, women whose marriage is not preceded by a first birth. Category 3 has those who become single parents. Category 4 has the women who cohabit at least once, but who do not marry or have a birth by age 24. The strictly ordered transitions of the 1950s are long gone and have been replaced by a variety of paths to adulthood. 相似文献
93.
How do marital status,work effort,and wage rates interact? 总被引:1,自引:0,他引:1
How marital status interacts with men's earnings is an important analytic and policy issue, especially in the context of debates in the United States over programs that encourage healthy marriage. This paper generates new findings about the earnings-marriage relationship by estimating the linkages among flows into and out of marriage, work effort, and wage rates. The estimates are based on National Longitudinal Survey of Youth panel data, covering 23 years of marital and labor market outcomes, and control for unobserved heterogeneity. We estimate marriage effects on hours worked (our proxy for work effort) and on wage rates for all men and for black and low-skilled men separately. The estimates reveal that entering marriage raises hours worked quickly and substantially but that marriage's effect on wage rates takes place more slowly while men continue in marriage. Together; the stimulus to hours worked and wage rates generates an 18%-19% increase in earnings, with about one-third to one-half of the marriage earnings premium attributable to higher work effort. At the same time, higher wage rates and hours worked encourage men to marry and to stay married. Thus, being married and having high earnings reinforce each other over time. 相似文献
94.
Motivated by problems in linguistics we consider a multinomial random vector for which the number of cells N is not much smaller than the sum of the cell frequencies, i.e. the sample size n . The distribution function of the uniform distribution on the set of all cell probabilities multiplied by N is called the structural distribution function of the cell probabilities. Conditions are given that guarantee that the structural distribution function can be estimated consistently as n increases indefinitely although n / N does not. The natural estimator is inconsistent and we prove consistency of essentially two alternative estimators. 相似文献
95.
96.
Urban Ecosystems - The urban landscape constitutes a key aspect of human - nature interactions, as more than 60% of the world’s population resides in cities and their suburbs. This study... 相似文献
97.
Rachel Shenhav‐Goldberg Robert Brym Talia Lenton‐Brym 《Revue canadienne de sociologie》2019,56(3):421-438
The theory of family welfare effort is a leading macro‐sociological explanation of variation in human fertility. It holds that states which provide universally available, inexpensive, high‐quality day care, generous parental leave, and flexible work schedules lower the opportunity cost of motherhood. They thus enable women, especially those in lower socioeconomic strata, to have the number of babies they want. A considerable body of research supports this theory. However, it is based almost exclusively on analyses of Western European and North American countries. This paper examines the Israeli case because Israel's total fertility rate is anomalously high given its family welfare effort. Based on a review of the relevant literature and a reanalysis of data from various published sources, it explains the country's unusually high total fertility rate as the product of (1) religious and nationalistic sentiment that is heightened by the Jewish population's perception of a demographic threat in the form of a burgeoning Palestinian population and (2) the state's resulting support for pro‐natal policies, including the world's most extensive in vitro fertilization (IVF) system. The paper also suggests that Israel's IVF policy may not be in harmony with the interests of many women insofar as even women with an extremely low likelihood of becoming pregnant are encouraged to undergo the often lengthy, emotionally and physically painful, and risky process of IVF. 相似文献
98.
Robert Werth 《Sociology Compass》2019,13(2)
In recent decades, risk prediction has proliferated in the penal realm. Risk instruments currently guide an array of correctional decisions—such as participation in diversion programs, the provision of correctional services, and probation and parole supervision levels—and are being increasingly utilized or considered in pretrial detention and criminal sentencing. This article reviews empirical and theoretical accounts of the proliferation and effects of risk in the penal realm and also reflects on ongoing debates about the promises and perils of risk. Risk techniques have impacted the practices, discourses, and logics of punishment. Yet they have not triggered the abandonment of rehabilitative approaches (or retributive ones), nor have they replaced human judgment with a rationalized utopia or iron cage. This article also offers several interventions that complicate and further our understandings of risk. First, it highlights the complex entanglements between, on the one hand, actuarial and algorithmic risk instruments and, on the other, subjective, moral, and affective methods of evaluation. Second, it calls for increased attention to the performative effects of risk technologies: to the ways in which assessments not only report on but also create and alter the social world. The article concludes by reflecting on emerging topics and directions for future research. 相似文献
99.
100.
Abigail R. Smith Nathan P. Goodrich Charlotte A. Beil Qian Liu Robert M. Merion Brenda W. Gillespie 《Journal of applied statistics》2019,46(9):1702-1713
Graphical representation of survival curves is often used to illustrate associations between exposures and time-to-event outcomes. However, when exposures are time-dependent, calculation of survival probabilities is not straightforward. Our aim was to develop a method to estimate time-dependent survival probabilities and represent them graphically. Cox models with time-dependent indicators to represent state changes were fitted, and survival probabilities were plotted using pre-specified times of state changes. Time-varying hazard ratios for the state change were also explored. The method was applied to data from the Adult-to-Adult Living Donor Liver Transplantation Cohort Study (A2ALL). Survival curves showing a ‘split’ at a pre-specified time t allow for the qualitative comparison of survival probabilities between patients with similar baseline covariates who do and do not experience a state change at time t. Time since state change interactions can be visually represented to reflect changing hazard ratios over time. A2ALL study results showed differences in survival probabilities among those who did not receive a transplant, received a living donor transplant, and received a deceased donor transplant. These graphical representations of survival curves with time-dependent indicators improve upon previous methods and allow for clinically meaningful interpretation. 相似文献