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81.
There was a time in this fair land when the railroad did not run When the wild majestic mountains stood alone against the
sun Long before the white man and long before the wheel When the green dark forest was too silent to be real
For they looked into the future and what did they see They saw an iron road running from the sea to the sea Bringing the goods
to a young growing land All up through the seaports and into their hands
From “Canadian Railroad Trilogy” by Gordon Lightfoot
The authors thank CPR managers and union officials representing CPR employees for their cooperation and patience in explaining
the intricacies of the railroad industry. Special appreciation is extended to Jason Copping, Labour Relations Manager, for
his facilitating our initial access to the company. 相似文献
82.
83.
Proponents of hazardous and nuclear waste depositories label opponents to local siting of such facilities “NIMBYs” (Not In My Backyard). This study assesses the extent to which the NIMBY label and the strategies of industry proponents to reduce opposition function on a reasonable set of assumptions. Using survey data and multiple regression techniques, the levels of concern of residents living in the county selected as the site of a low level radioactive waste disposal facility (imminent threat condition) are compared with a statewide sample (hypothetical threat condition). Consistent with proponents' theoretical assumptions, the levels of concern are greater for respondents under conditions of imminent threat than of hypothetical threat. However, within the host county, levels of concern are lowest, albeit most polarized, in the community closest to the proposed site. A conflict theory approach enhances an understanding of these findings by suggesting that within the most proximate community levels of concern are lowest for citizens who stand to gain the most economic benefits from the facility but highest for those citizens who are least likely to derive tangible gains. 相似文献
84.
The small sample performance of least median of squares, reweighted least squares, least squares, least absolute deviations, and three partially adaptive estimators are compared using Monte Carlo simulations. Two data problems are addressed in the paper: (1) data generated from non-normal error distributions and (2) contaminated data. Breakdown plots are used to investigate the sensitivity of partially adaptive estimators to data contamination relative to RLS. One partially adaptive estimator performs especially well when the errors are skewed, while another partially adaptive estimator and RLS perform particularly well when the errors are extremely leptokur-totic. In comparison with RLS, partially adaptive estimators are only moderately effective in resisting data contamination; however, they outperform least squares and least absolute deviation estimators. 相似文献
85.
William G. Herron Rafael Art Javier Maura McDonald-Gomez Lydia K. Adlerstein 《Journal of Social Distress and the Homeless》1994,3(3):213-228
This paper suggests a direction for the exploration of the causes of family violence. Explanatory models of family violence were considered in this regard, with the recommendation that a multi-determined model should be considered to ensure the most accurate explanation. We suggest that family violence will be best understood and prevented or alleviated, if a model is used that considers the interaction of structural violence and the personality features of all the family members. 相似文献
86.
Sources of drug information among adolescent students 总被引:1,自引:0,他引:1
E Mirzaee P M Kingery B E Pruitt G Heuberger R S Hurley 《Journal of drug education》1991,21(2):95-106
A sample of 1023 eighth and tenth grade students in small to medium-sized central Texas school districts was assessed to determine the amount of information they receive from ten sources about six categories of drugs. The amount of information males reported receiving about each drug category was significantly greater than what females reported, and the amount of information that eighth graders reported receiving about each drug category was significantly greater than what tenth graders reported. Television was the primary source of drug information for all categories of drugs except inhalants, for which friends and television were equally important sources. Parents and printed media (magazines or newspapers) were of secondary importance, followed by friends and teachers. Adolescents were less likely to receive drug-related information from experience, siblings, church, doctors, and police. The reliance on the mass media for drug information in smaller school districts is a pattern which has been previously observed in larger urban districts. This consistency suggests that mass media approaches to drug education are likely to be as effective in rural areas and smaller towns as they are among urban adolescents. Implications for television programming are discussed. 相似文献
87.
This study investigates the extent and nature of housing affordability for elderly nonmetropolitan female heads of household
using data from the Panel Study of Income Dynamics. The results indicate that over one-third of elderly nonmetropolitan female
heads of household experience housing poverty and that those who rent, who have fair to poor health, and who are minorities
are particularly vulnerable. Housing affordability, measured by the concept of housing poverty, identifies households struggling
to meet basic needs while the conventional 25% of income for housing expenditures ratio identifies a larger population. The
findings suggest the need for multifaceted public policies to address the problem of housing poverty.
Her research interests include housing affordability, housing and community vitality, and decision making. She received her
Ph.D. from Purdue University.
Sooyoun Park is in the same department as a Project Assistant on a USDA-funded research project entitled “Housing Affordability
in Rural Areas,” which is a joint project between Nebraska and Wisconsin. Her research interests focus on housing management
behavior in relation to housing expenditure burden. She received her Ph.D. from the University of Nebraska-Lincoln. 相似文献
88.
K. A. Ariyawansa 《Statistical Papers》1994,35(1):139-150
While applying theclassical maximum likelihood method for a certain statistical inference problem, Smith and Weissman [5] have noted that there are conditions
under which the likelihood function may be unbounded above or may not possess local maximizers. Ariyawansà and Templeton [1]
have derived inference procedures for this problem using the theory of structural inference [2,3,4]. Based on numerical experience,
and without proof, they state that the resulting likelihood functions possess unique, global maximizers, even in instances
where the classical maximum likelihood method fails in the above sense. In this paper, we prove that under quite mild conditions,
these likelihood functions that result from the application of the theory of structural inference are well-behaved, and possess
unique, global maximizers.
This research was supported in part by the Applied Mathematical Sciences subprogram of the U.S. Department of Energy under
contract W-31-109-Eng-38 while the author was visiting the Mathematics and Computer Science Division of Argonne National Laboratory,
Argonne, Illinois. 相似文献
89.
Annual concentrations of toxic air contaminants are of primary concern from the perspective of chronic human exposure assessment and risk analysis. Despite recent advances in air quality monitoring technology, resource and technical constraints often impose limitations on the availability of a sufficient number of ambient concentration measurements for performing environmental risk analysis. Therefore, sample size limitations, representativeness of data, and uncertainties in the estimated annual mean concentration must be examined before performing quantitative risk analysis. In this paper, we discuss several factors that need to be considered in designing field-sampling programs for toxic air contaminants and in verifying compliance with environmental regulations. Specifically, we examine the behavior of SO2, TSP, and CO data as surrogates for toxic air contaminants and as examples of point source, area source, and line source-dominated pollutants, respectively, from the standpoint of sampling design. We demonstrate the use of bootstrap resampling method and normal theory in estimating the annual mean concentration and its 95% confidence bounds from limited sampling data, and illustrate the application of operating characteristic (OC) curves to determine optimum sample size and other sampling strategies. We also outline a statistical procedure, based on a one-sided t-test, that utilizes the sampled concentration data for evaluating whether a sampling site is compliance with relevant ambient guideline concentrations for toxic air contaminants. 相似文献
90.
John E. Roemer 《Social Choice and Welfare》1994,11(4):355-380
Voter preferences are characterized by a parameter s (say, income) distributed on a set S according to a probability measure F. There is a single issue (say, a tax rate) whose level, b, is to be politically decided. There are two parties, each of which is a perfect agent of some constituency of voters, voters with a given value of s. An equilibrium of the electoral game is a pair of policies, b 1 and b 2, proposed by the two parties, such that b i maximizes the expected utility of the voters whom party i represents, given the policy proposed by the opposition. Under reasonable assumptions, the unique electoral equilibrium consists in both parties proposing the favorite policy of the median voter. What theory can explain why, historically, we observe electoral equilibria where the ‘right’ and ‘left’ parties propose different policies? Uncertainty concerning the distribution of voters is introduced. Let {F(t)} t ε T be a class of probability measures on S; all voters and parties share a common prior that the distribution of t is described by a probability measure H on T. If H has finite support, there is in general no electoral equilibrium. However, if H is continuous, then electoral equilibrium generally exists, and in equilibrium the parties propose different policies. Convergence of equilibrium to median voter politics is proved as uncertainty about the distribution of voter traits becomes small. 相似文献