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341.
A U.S. household panel is used to estimate a model of household purchases of butter, margarine and butter/margarine blends. The econometric model accounts for the discrete purchase decisions process and the censored nature of disaggregated commodity demand. Observed market prices are "quality" adjusted for the three commodities investigated based on household and purchase characteristics. Over 90% of the reaction to a price change is found to occur with respect to the decision whether or not to consume.  相似文献   
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Abstract. This research re-examines whether there are differences in the forecast accuracy of financial analysts through a comparison of their annual earnings per share forecasts. The comparison of analyst forecast accuracy is made on both an ex post (within sample) and an ex ante (out of sample) basis. Early examinations of this issue by Richards (1976), Brown and Rozeff (1980), O'Brien (1987), Coggin and Hunter (1989), O'Brien (1990), and Butler and Lang (1991) were ex post and suggest the absence of analysts who can provide relatively more accurate forecasts over multiple years. Contrary to the results of prior research and consistent with the belief in the popular press, we document that differences do exist in financial analysts' ex post forecast accuracy. We show that the previous studies failed to find differences in forecast accuracy due to inadequate (or no) control for differences in the recency of forecasts issued by the analysts. It has been well documented in the literature that forecast recency is positively related to forecast accuracy (Crichfield, Dyckman, and Lakonishok 1978; O'Brien 1988; Brown 1991). Thus, failure to control for forecast recency may reduce the power of tests, making it difficult to reject the null hypothesis of no differences in forecast accuracy even if they do exist. In our analysis, we control for the differences in recency of analysts' forecasts using two different approaches. First, we use an estimated generalized least squares estimation procedure that captures the recency-induced effects in the residuals of the model. Second, we use a matched-pair design whereby we measure the relative forecast accuracy of an analyst by comparing his/her forecast error to the forecast error of another randomly selected analyst making forecasts for the same firm in the same year on or around the same date. Using both approaches, we find that differential forecast accuracy does exist amongst analysts, especially in samples with minimum forecast horizons of five and 60 trading days. We show that these differences are not attributable to differences in the forecast issuance frequency of the financial analysts. In sum, after controlling for firm, year, forecast recency, and forecast issuance frequency of individual analysts, the analyst effect persists. To validate our findings, we examine whether the differences in the forecast accuracy of financial analysts persist in holdout periods. Analysts were assigned a “superior” (“inferior”) status for a firm-year in the estimation sample using percentile rankings on the distribution of absolute forecast errors for that firm-year. We use estimation samples of one- to four-year duration, and consider two different definitions of analyst forecast superiority. Analysts were classified as firm-specific “superior” if they maintained a “superior” status in every year of the estimation sample. Furthermore, they were classified as industry-specific “superior” if they were deemed firm-specific “superior” with respect to at least two firms and firm-specific “inferior” with respect to no firm in that industry. Using either definition, we find that analysts classified as “superior” in estimation samples generally remain superior in holdout periods. In contrast, we find that analysts identified as “inferior” in estimation samples do not remain inferior in holdout periods. Our results suggest that some analysts' earnings forecasts should be weighted higher than others when formulating composite earnings expectations. This suggestion is predicated on the assumption that capital markets distinguish between analysts who are ex ante superior, and that they utilize this information when formulating stock prices. Our study provides an ex ante framework for identifying those analysts who appear to be superior. When constructing weighted forecasts, a one-year estimation period should be used because we obtain the strongest results of persistence in this case.  相似文献   
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Within the context of a linear Leontief model, the LeChatelier-Samuelson principle examines the effects of an increase in some final demand on the output levels under the constraint that the production of certain goods is held at its original value. The principle states that the increase in any output is larger when fewer output levels are kept constant. The present paper discusses bounds for such incremental changes, second-order effects, the consequences on the markets for the products with restricted output levels, and generalizations of the original assumptions.I would like to thank two anonymous referees for their helpful comments.  相似文献   
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Numerous labor-management issues possess ethical dimensions and pose ethical questions. In this article, the authors discuss four labor-management issues that present important contemporary problems: union organizing, labor-management negotiations, employee involvement programs, and union obligations of fair representation. In the authors view, labor and management too often view their ethical obligations as beginning and ending at the law's boundaries. Contemporary business realities suggest that cooperative and enlightened modes of interaction between labor and management seem appropriate.Robert S. Adler is Associate Professor of Legal Studies at the Kenan-Flagler Business School, University of North Carolina at Chapel Hill. He teaches courses in Business Law, Business Ethics, and Regulation. Prior to coming to UNC, Professor Adler served as Counsel to the Subcommittee on Health and the Environment of the Committee on Energy and Commerce of the U.S. House of Representatives.William J. Bigoness is Professor of Business Administration and Director, Center for Management Studies at the Kenan-Flagler Business School, University of North Carolina at Chapel Hill. His professional interests include organizational behavior, human resource management, and labor-management relations. Dr. Bigoness was Visiting Professor of Business Administration at the International Institute for Management Development (IMD) located in Lausanne, Switzerland from 1985 to 1987.  相似文献   
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How to transform a failed socialist economy raises questions about the processes of structural and institutional changes, which standard economics is inadequately equipped to study. An economic theory that can study both these processes is suggested and applied to the actual debate of how the transformation should be conducted. Standard notions of institutional roles (R) and organizational structures (S) are seen in a non-standard way as outcomes of two interrelated but distinct evolutions. Comparing different given Rs for their influence on S-evolution throws new light on which R should be the target of the transformation. Compared to standard analysis, the case against socialism on the supply side is strengthened, whereas the case against a redistributive welfare society on the demand side is weakened. S-evolution is shown to require more time and be more difficult to be helped by government than R-evolution. This clarifies several controversial points about the speed and the sequencing of the transformation policies. The study of R-evolution discloses an important cognitive constraint on these policies, which teaching of economics can help to soften. Standard economics, shown to be a special case of the suggested theory, is rehabilitated as the best subject by which such teaching should start.  相似文献   
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This paper examines the influence of unemployment insurance (UI) on the length of nonemployment spells experienced by young workers. The analysis introduces a flexible duration model to estimate the effects of the weekly benefit amount and weeks of eligibility on the amount of time spent between jobs by men, distinguishing between the experiences of UI and non-UI recipients. The empirical findings suggest three conclusions: (1) UI recipients experience longer spells of nonemployment than their non-UI recipient counterparts, at least up to the point of exhaustion of UI benefits; (2) the level of the weekly benefit amount does not significantly affect the length of nonemployment spells; and (3) increasing the number of weeks of eligibility offered by a UI program leads to longer episodes of nonemployment.  相似文献   
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