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991.
Is Nature‐Oriented Tourism a Pro‐Environmental Practice?: Examining Tourism–Environmentalism Alignments Through Discourse Networks and Intersectoral Relationships
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A key tenet of ecotourism is that interacting with nature through tourism cultivates environmental awareness and responsibility. We examine this assumption by analyzing discourse networks and organizational networks that connect tourism and environmentalism in Newfoundland and Labrador, Canada. Using a combination of interviews, field observation, and web‐based data, we ask: Is there an alignment of tourism and environmental discourse regarding human interaction with and use of coastal environments? Are there meaningful organizational ties between tourism and environmental organizations? We conclude that there is little indication that nature‐oriented tourism is working to produce substantial changes to our broader political ecology. 相似文献
992.
“Know What to Do If You Encounter a Flash Flood”: Mental Models Analysis for Improving Flash Flood Risk Communication and Public Decision Making
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Heather Lazrus Rebecca E. Morss Julie L. Demuth Jeffrey K. Lazo Ann Bostrom 《Risk analysis》2016,36(2):411-427
Understanding how people view flash flood risks can help improve risk communication, ultimately improving outcomes. This article analyzes data from 26 mental models interviews about flash floods with members of the public in Boulder, Colorado, to understand their perspectives on flash flood risks and mitigation. The analysis includes a comparison between public and professional perspectives by referencing a companion mental models study of Boulder‐area professionals. A mental models approach can help to diagnose what people already know about flash flood risks and responses, as well as any critical gaps in their knowledge that might be addressed through improved risk communication. A few public interviewees mentioned most of the key concepts discussed by professionals as important for flash flood warning decision making. However, most interviewees exhibited some incomplete understandings and misconceptions about aspects of flash flood development and exposure, effects, or mitigation that may lead to ineffective warning decisions when a flash flood threatens. These include important misunderstandings about the rapid evolution of flash floods, the speed of water in flash floods, the locations and times that pose the greatest flash flood risk in Boulder, the value of situational awareness and environmental cues, and the most appropriate responses when a flash flood threatens. The findings point to recommendations for ways to improve risk communication, over the long term and when an event threatens, to help people quickly recognize and understand threats, obtain needed information, and make informed decisions in complex, rapidly evolving extreme weather events such as flash floods. 相似文献
993.
Mark Steyvers Thomas S. Wallsten Edgar C. Merkle Brandon M. Turner 《Risk analysis》2014,34(3):435-452
We propose the use of signal detection theory (SDT) to evaluate the performance of both probabilistic forecasting systems and individual forecasters. The main advantage of SDT is that it provides a principled way to distinguish the response from system diagnosticity, which is defined as the ability to distinguish events that occur from those that do not. There are two challenges in applying SDT to probabilistic forecasts. First, the SDT model must handle judged probabilities rather than the conventional binary decisions. Second, the model must be able to operate in the presence of sparse data generated within the context of human forecasting systems. Our approach is to specify a model of how individual forecasts are generated from underlying representations and use Bayesian inference to estimate the underlying latent parameters. Given our estimate of the underlying representations, features of the classic SDT model, such as the receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC), follow immediately. We show how our approach allows ROC curves and AUCs to be applied to individuals within a group of forecasters, estimated as a function of time, and extended to measure differences in forecastability across different domains. Among the advantages of this method is that it depends only on the ordinal properties of the probabilistic forecasts. We conclude with a brief discussion of how this approach might facilitate decision making. 相似文献
994.
995.
Carlos Trucíos Luiz K. Hotta Esther Ruiz 《Journal of Statistical Computation and Simulation》2017,87(16):3152-3174
Bootstrap procedures are useful to obtain forecast densities for both returns and volatilities in the context of generalized autoregressive conditional heteroscedasticity models. In this paper, we analyse the effect of additive outliers on the finite sample properties of these bootstrap densities and show that, when obtained using maximum likelihood estimates of the parameters and standard filters for the volatilities, they are badly affected with dramatic consequences on the estimation of Value-at-Risk. We propose constructing bootstrap densities for returns and volatilities using a robust parameter estimator based on variance targeting implemented together with an adequate modification of the volatility filter. We show that the performance of the proposed procedure is adequate when compared with available robust alternatives. The results are illustrated with both simulated and real data. 相似文献
996.
Urban and agricultural soils: conflicts and trade-offs in the optimization of ecosystem services 总被引:2,自引:0,他引:2
H. Setälä R. D. Bardgett K. Birkhofer M. Brady L. Byrne P. C. de Ruiter F. T. de Vries C. Gardi K. Hedlund L. Hemerik S. Hotes M. Liiri S. R. Mortimer M. Pavao-Zuckerman R. Pouyat M. Tsiafouli W. H. van der Putten 《Urban Ecosystems》2014,17(1):239-253
On-going human population growth and changing patterns of resource consumption are increasing global demand for ecosystem services, many of which are provided by soils. Some of these ecosystem services are linearly related to the surface area of pervious soil, whereas others show non-linear relationships, making ecosystem service optimization a complex task. As limited land availability creates conflicting demands among various types of land use, a central challenge is how to weigh these conflicting interests and how to achieve the best solutions possible from a perspective of sustainable societal development. These conflicting interests become most apparent in soils that are the most heavily used by humans for specific purposes: urban soils used for green spaces, housing, and other infrastructure and agricultural soils for producing food, fibres and biofuels. We argue that, despite their seemingly divergent uses of land, agricultural and urban soils share common features with regards to interactions between ecosystem services, and that the trade-offs associated with decision-making, while scale- and context-dependent, can be surprisingly similar between the two systems. We propose that the trade-offs within land use types and their soil-related ecosystems services are often disproportional, and quantifying these will enable ecologists and soil scientists to help policy makers optimizing management decisions when confronted with demands for multiple services under limited land availability. 相似文献
997.
In this article, we consider Bayesian inference procedures to test for a unit root in Stochastic Volatility (SV) models. Unit-root tests for the persistence parameter of the SV models, based on the Bayes Factor (BF), have been recently introduced in the literature. In contrast, we propose a flexible class of priors that is non-informative over the entire support of the persistence parameter (including the non-stationarity region). In addition, we show that our model fitting procedure is computationally efficient (using the software WinBUGS). Finally, we show that our proposed test procedures have good frequentist properties in terms of achieving high statistical power, while maintaining low total error rates. We illustrate the above features of our method by extensive simulation studies, followed by an application to a real data set on exchange rates. 相似文献
998.
Goodness-of-fit tests for the family of symmetric normal inverse Gaussian distributions are constructed. The tests are based on a weighted integral incorporating the empirical characteristic function of suitably standardized data. An EM-type algorithm is employed for the estimation of the parameters involved in the test statistic. Monte Carlo results show that the new procedure is competitive with classical goodness-of-fit methods. An application with financial data is also included. 相似文献
999.
Valeria Bordone Francesco C. Billari Gianpiero Dalla Zuanna 《Statistical Methods and Applications》2009,18(3):445-451
The own-children method (OCM) applied to the Italian Labour Force Survey (ILFS) is an alternative way to give information
on fertility for the years before the survey. By deriving children information and the population at risk on the basis of
parents’ characteristics, a large-scale dataset for fertility analysis in Italy becomes available, also to reconstruct event
histories. The quality assessment provided by comparing the total fertility rate (TFR) calculated on ILFS with the official
regional and national TFRs by ISTAT gives us usable outcomes. 相似文献
1000.
Arijit Chaudhuri Tasos C. Christofides Amitava Saha 《Statistical Methods and Applications》2009,18(3):389-418
In estimating the proportion of people bearing a sensitive attribute A, say, in a given community, following Warner’s (J Am Stat Assoc 60:63–69, 1965) pioneering work, certain randomized response
(RR) techniques are available for application. These are intended to ensure efficient and unbiased estimation protecting a
respondent’s privacy when it touches a person’s socially stigmatizing feature like rash driving, tax evasion, induced abortion,
testing HIV positive, etc. Lanke (Int Stat Rev 44:197–203, 1976), Leysieffer and Warner (J Am Stat Assoc 71:649–656, 1976),
Anderson (Int Stat Rev 44:213–217, 1976, Scand J Stat 4:11–19, 1977) and Nayak (Commun Stat Theor Method 23:3303–3321, 1994)
among others have discussed how maintenance of efficiency is in conflict with protection of privacy. In their RR-related activities
the sample selection is traditionally by simple random sampling (SRS) with replacement (WR). In this paper, an extension of
an essential similarity in case of general unequal probability sample selection even without replacement is reported. Large
scale surveys overwhelmingly employ complex designs other than SRSWR. So extension of RR techniques to complex designs is
essential and hence this paper principally refers to them. New jeopardy measures to protect revelation of secrecy presented
here are needed as modifications of those in the literature covering SRSWR alone. Observing that multiple responses are feasible
in addressing such a dichotomous situation especially with Kuk’s (Biometrika 77:436–438, 1990) and Christofides’ (Metrika
57:195–200, 2003) RR devices, an average of the response-specific jeopardizing measures is proposed. This measure which is
device dependent, could be regarded as a technical characteristic of the device and it should be made known to the participants
before they agree to use the randomization device.
The views expressed are the authors’, not of the organizations they work for. Prof Chaudhuri’s research is partially supported
by CSIR Grant No. 21(0539)/02/EMR-II. 相似文献