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991.
Life and philanthropy are eternal themes in human history.Iflifesymbolizes a miraculous gift,thenphilanthropycan be considered as the dramatic highlight and spectacular display of one's life process. With their life-long dedication to the causes of philanthropy,Dr.David K.K.Chan and Ms.Law Meiling have successfully explored a new operational model of philanthropy,which is the combination of business elements with philanthropy.This model must,first of all,resolve those issues that are related to funding,a...  相似文献   
992.
Ash emitted from the Eyjafjallajökull Icelandic volcano resulted in the closure UK’s airspace in 2010. This research highlights passengers experience throughout the crisis and it is impacted on their wellbeing. Analysis of a survey shows that just 90% of respondents highlighted the failure of airline, travel agencies and/or government to provide timely and appropriate information. The airspace closure also caused adverse health impacts, with 79% of respondents highlighting this as a concern. Although passengers were greatly inconvenienced and had a negative experience, seventy-nine percent of respondents indicated that the crisis had little or no impact on their decision to fly in the future.  相似文献   
993.
Volatility, exponential smoothing, regression and Naïve 2 models are considered singly and in combination in terms of forecasting demand for international tourism. These models generate accurate predictions of tourism flows, but their prime utility is when combined with other models. Usually, models are combined by means of purely statistical criteria. We show that goal programming (GP) offers an alternative, flexible approach to model combination. GP offers planners a practical solution to tourism forecasting problems, since the method is more adaptable than conventional minimisation of prediction error, by permitting practitioners to prioritise a series of management related goals. Forecasters can focus on longer- and short-term goals, minimising forecast under- and over-estimation and/or concentrate on prediction errors in tourism flows at various times of the year.  相似文献   
994.
Overreaction to Fearsome Risks   总被引:1,自引:0,他引:1  
When risks threaten, cognitive mechanisms bias people toward action or inaction. Fearsome risks are highly available. The availability bias tells us that this leads people to overestimate their frequency. Therefore, they also overreact to curtail the likelihood or consequences of such risks. More generally, fear can paralyze efforts to think clearly about risks. We draw on a range of environmental risks to show the following: (1) Fear leads us to neglect probability of occurrence; (2) As fearsome environmental risks are usually imposed by others (as externalities), indignation stirs excess reaction; (3) We often misperceive or miscalculate such risks. Two experiments demonstrate probability neglect when fearsome risks arise: (a) willingness-to-pay to eliminate the cancer risk from arsenic in water (described in vivid terms) did not vary despite a 10-fold variation in risk; (b) the willingness-to-accept price for a painful but non dangerous electric shock did not vary between a 1 and 100% chance. Possible explanations relate to the role of the amygdala in impairing cognitive brain function. Government and the law, both made by mortals and both responding to public pressures, similarly neglect probabilities for fearsome risks. Examples relating to shark attacks, Love Canal, alar and terrorism are discussed.  相似文献   
995.
We discuss an approach to modeling the slack season provision of guided tours to tourists that accounts for the twin phenomena of stochastic demand and tourist heterogeneity but is different from the way in which this problem has been modeled in the extant tourism literature. Our discussion uses the theory of discrete-time Markov chains and it models the slack season from a tourist demand perspective. Specifically, we first study a case in which the wait plus tour or the excursion time of an arriving tourist is exponentially distributed with a fixed mean. Next, we focus on a scenario in which the excursion time is exponentially distributed with one of two possible fixed means and these two means arise with specific probabilities.  相似文献   
996.
997.
Knoblock and Korf have determined that abstraction can reduce search at a single agent from exponential to linear complexity (Knoblock 1991; Korf 1987). We extend their results by showing how concurrent problem solving among multiple agents using abstraction can further reduce search to logarithmic complexity. We empirically validate our formal analysis by showing that it correctly predicts performance for the Towers of Hanoi problem (which meets all of the assumptions of the analysis). Furthermore, a powerful form of abstraction for large multiagent systems is to group agents into teams, and teams of agents into larger teams, to form an organizational pyramid. We apply our analysis to such an organization of agents and demonstrate the results in a delivery task domain. Our predictions about abstraction's benefits can also be met in this more realistic domain, even though assumptions made in our analysis are violated. Our analytical results thus hold the promise for explaining in general terms many experimental observations made in specific distributed AI systems, and we demonstrate this ability with examples from prior research.This research has been sponsored, in part, by the National Science Foundation under grants IRI-9015423 and IRI-9010645, by the University of Michigan Rackham Graduate School, and by a Bell Northern Research Postgraduate Award.  相似文献   
998.
This study was designed to examine the determinants of and differences between the ethical beliefs of two groups of Japanese students in religious and secular universities. Multiple regression analysis revealed that students of the Japanese religious university perceived that young, male, relativistic, and opportunistic students tended to behave less ethically than did older, female, and idealistic students. Students of the Japanese secular university perceived that male, achievement-oriented, and opportunistic students tended to behave less ethically than did female and experience-oriented students. Opportunism was found to be one of the most important determinants in explaining misconduct. Multivariate analysis of variance (MANOVA) and multiple discriminant analysis (MDA) revealed that students of the Japanese secular university tended to score higher on achievement and humanism, and lower on theism and positivism than did students of the Japanese religious university. In addition, students of the Japanese secular university were somewhat more sensitive to academic dishonesty practices than were students of the Japanese religious university.  相似文献   
999.
Monetary budgets influence activity participation and related travel as they demarcate limits on how people organize their activities in time and space. In this paper, we are interested in money allocation to out-of-home leisure activities and how this is affected by duration, sociodemographics, and time-location variables. Analyses were carried out by applying a seemingly unrelated regression model to a leisure activity data set. The analyses revealed that expenditures for out-of-home leisure activities are influenced by the variables mentioned above. Moreover, the results indicate that there is a substitution between expenditure of each activity.  相似文献   
1000.
Prior literature suggests that the market underreacts to the positive correlation in a typical firm's seasonal earnings changes, which leads to a post‐earnings‐announcement drift (PEAD) in prices. We examine the market reaction for a distinct set of firms whose seasonal earnings changes are uncorrelated and show that the market incorrectly assumes that the earnings changes of these firms are positively correlated. We also document that positive (negative) seasonal earnings changes in the current quarter are associated with negative (positive) abnormal returns in the next quarter. Thus, we observe a reversal of abnormal returns, consistent with a systematic overreaction to earnings, rather than the previously documented PEAD. Additional analysis indicates that financial analysts similarly overestimate the autocorrelation of these firms, although to a lesser extent. We also find that the magnitude of overestimation and the subsequent price reversal are inversely related to the richness of the information environment. Our results challenge the notion that investors recognize but consistently underestimate earnings correlation and provide a new perspective on the inability of prices to fully reflect the implications of current earnings for future earnings. That is, we show that investors predictably overestimate correlation when it is lacking, but underestimate it when it is present.  相似文献   
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