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931.
The analysis of categorical response data through the multinomial model is very frequent in many statistical, econometric, and biometric applications. However, one of the main problems is the precise estimation of the model parameters when the number of observations is very low. We propose a new Bayesian estimation approach where the prior distribution is constructed through the transformation of the multivariate beta of Olkin and Liu (2003). Moreover, the application of the zero-variance principle allows us to estimate moments in Monte Carlo simulations with a dramatic reduction of their variances. We show the advantages of our approach through applications to some toy examples, where we get efficient parameter estimates. 相似文献
932.
The power method transformation is a popular algorithm used for simulating correlated non normal continuous variates because of its simplicity and ease of execution. Statistical models may consist of continuous and (or) ranked variates. In view of this, the methodology is derived for simulating controlled correlation structures between non normal (a) variates, (b) ranks, and (c) variates with ranks in the context of the power method. The correlation structure between variate-values and their associated rank-order is also derived for the power method. As such, a measure of the potential loss of information is provided when ranks are used in place of variate-values. The results of a Monte Carlo simulation are provided to confirm and demonstrate the methodology. 相似文献
933.
Governments sometimes characterize torture as an indispensable interrogation tool for gathering strategic intelligence. In this article, we review the relevant social scientific research on the effectiveness, impact, and causes of torture. First, we summarize research on false confessions and examine the relevance of that research for torture-based interrogations. Next, we review research on the mental health consequences of torture for survivors and perpetrators. Finally, we explore the social-psychological conditions that promote acts of cruelty (such as those seen at Abu Ghraib) and examine the arguments typically offered to justify the use of torture. We argue that any hypothesized benefits from the use of torture must be weighed against the substantial proven costs of torture. These costs include the unreliable information extracted through interrogations using torture, the mental and emotional toll on victims and torturers, loss of international stature and credibility, and the risk of retaliation against soldiers and civilians. 相似文献
934.
Objectives. Conventional theory regarding externalities and personal choices implies that in the absence of negative externalities, there is no economic rationale for government to regulate or ban those choices. We evaluate whether legally recognizing (or prohibiting) same‐sex marriage has any adverse impact on societal outcomes specifically related to “traditional family values.” Methods. Using data from 1990 to 2004 in the U.S. states, with statistical controls appropriate for the particular model, and with fixed effects, we test the claim of the Family Research Council that same‐sex marriage will have negative impacts on marriage, divorce, abortion rates, the proportion of children born to single women, and the percent of children in female‐headed households. Results. We find no statistically significant adverse effect from allowing gay marriage. Bans on gay marriage, when they are not overturned, appear to be associated with a lower abortion rate and a lower percentage of children in female‐headed households. However, allowing gay marriage also shows the same or stronger associations. Conclusions. The argument that same‐sex marriage poses a negative externality on society cannot be rationally held. Although many might believe that this conclusion is so obvious that it does not warrant testing, many politicians use this argument as a fact‐based rationale to legitimize bans on same‐sex marriage. 相似文献
935.
Objective. Anti‐Americanism has been subjected to minimal statistical analysis. Further, scant attention is paid to what constitutes anti‐Americanism for Americans. The objective of this article is to measure Americans' perceptions of anti‐Americanism. Methods. Using a range of quantitative methods, including Pearson's correlation coefficient, Shannon's entropy measure, and Cohen's d statistics, we measure students' evaluations of editorial cartoons after 9/11. Twin measures of message and equity, along with participant and cartoon variables, are used to calibrate anti‐Americanism in Spanish and U.S. editorial cartoons. Results. Our results indicate that message ratings, that is, anti‐ or pro‐American, were more dependent on the nature of the cartoons than of the participants. White males rated these editorial cartoons as more equitable than other participants. The study shows that Spanish cartoons were rated significantly more anti‐American. Conclusion. The article concludes that the use of U.S. icons is key to seeing anti‐Americanism, along with gender, race, and origin of cartoon. 相似文献
936.
Commodity prices often fluctuate significantly from one purchasing opportunity to the next. These fluctuations allow firms to benefit from forward buying (buying for future demand in addition to current demand) when prices are low. We propose a combined heuristic to determine the optimal number of future periods a firm should purchase at each ordering opportunity in order to maximize total expected profit when there is uncertainty in future demand and future buying price. We compare our heuristic with existing methods via simulation using real demand data from BlueLinx, a two-stage distributor of building products. The results show that our combined heuristic performs better than any existing methods considering forward buying or safety stock separately. We also compare our heuristic to the optimal inventory management policy by full enumeration for a smaller data set. The proposed heuristic is shown to be close to optimal. This study is the first to decide both the optimal number of future periods to buy for uncertain purchase price and the appropriate purchasing quantity with safety stock for uncertain demand simultaneously. The experience suggests that the proposed combined heuristic is simple and can be very beneficial for any company where forward buying is possible. 相似文献
937.
938.
Breaking ground from all previous studies, we estimate a time-varying Vector Autoregression model that examines the time-period 1270–2016 — the entire economic history of the U.K. Focusing on permanent and transitory shocks in the economy, we study the fluctuation in conditional volatilities and time-varying long-run responses of output growth and inflation. Unlike all previous studies that use time invariant linear models, our approach reveals that the pre 1600 period is a turbulent economic period of high volatility that is only repeated in the 20th century. The repeating patterns in the conditional volatilities follow from aggregate supply shocks, while most of the inflation responses follow from aggregate demand shocks. Thus, we uncover that despite the technological growth and the various changes in the structure of the U.K. economy in the last century, the recurring patterns call for an examination of the true impact of the various policies on the economy. 相似文献
939.
Mark Schneider Jonathan W. Leland Nathaniel T. Wilcox 《Journal of Risk and Uncertainty》2018,57(2):133-151
In his exposition of subjective expected utility theory, Savage (1954) proposed that the Allais paradox could be reduced if it were recast into a format which made the appeal of the independence axiom of expected utility theory more transparent. Recent studies consistently find support for this prediction. We consider a salience-based choice model which explains this frame-dependence of the Allais paradox. We then derive the novel prediction that the presentation format responsible for reductions in Allais-style violations of expected utility theory will also reduce Ellsberg-style violations of subjective expected utility theory. This format makes the appeal of Savage’s “sure thing principle” more transparent. We design an experiment to test this prediction and find strong support for such frame-dependence of ambiguity aversion in Ellsberg-style choices. In particular, we observe markedly less ambiguity-averse behavior in Savage’s matrix format than in a more standard “prospect” format. This finding poses a new challenge for the leading models of ambiguity aversion. 相似文献
940.
Tebeau M 《Journal of social history》2010,44(2):327-350
Perhaps the world's first peace garden, the Cleveland Cultural Gardens embody the history of twentieth-century America and reveal the complex interrelations between art and place. This essay uses the Cleveland Cultural Gardens as a lens through which to explore how art and place have intersected over time. It explores how communities have negotiated questions of national, ethnic, and American identity and embedded those identities into the vernacular landscape. It considers how the particulars of place were embedded into a public garden and asks whether it is possible for public art to transcend its place—both in terms of geography and history. In some sense, the Gardens have transcended their place, but in others respects, their fortunes were bound inextricably to that place, to the economic, demographic, and cultural contours that shaped and reshaped Northern Ohio. As works of art, the Cleveland Cultural Gardens both have reflected the history of Cleveland and American industrial cities during the 20th century and revealed something of the dynamics that underscored the changing character of public art and gardens in American cities. 相似文献