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41.
P. Mukhopadhyay 《Metrika》1975,22(1):119-127
The problem of constructing a sampling design with the value of the sum of second order inclusion probabilities attaining its lower bound for non-integral values of the expected effective size of a sample in the design has been considered in this paper. If the values of the characteristic of interest on all the units in the population are non-negative the design is admissible (in the sense of variance) with respect to Horvitz-Thompson estimator in the class of designs with the same set of values of the first order inclusion probabilities of the units. Again such a design is best to use Horvitz-Thompson estimator of population total in the sense of smallest average variance of the estimator under a special superpopulatio model. 相似文献
42.
John P. Dickson Douglas L. MacLachlan 《Journal of the Academy of Marketing Science》1990,18(2):153-161
This research was designed to see whether a reconceptualization of social distance (as measured by social class variables)
between shoppers and stores would provide a basis for understanding store avoidance behavior. A survey of shoppers classified
into two distinct social classes investigated their images, including social class images, of two stores that had been selected
as representatives of upscale and downscale retailers. A new measure of social distance was proposed and evaluated. Controlling
for other functional aspects of store image such as price and personnel, the social distance measure was found to be influential
in discriminating shopping frequency groups for the two stores, providing evidence that people tend to avoid stores that are
perceived as being socially distant from themselves. 相似文献
43.
Richard T. Hise D.B.A. Jan P. Muczyk D.B.A. 《Journal of the Academy of Marketing Science》1977,5(1-2):126-133
Previous studies of the driving times of shopping center patrons have not examined the effect of limited access highways.
This study analyzed the impact of interstate highways on the driving times of 204 shoppers at three medium-sized regional
shopping centers. Those shoppers indicating usage of interstate highways to reach their shopping destinations were significantly
more likely to incur travel times greater than fifteen and twenty minutes than those not using the available interstate roads.
In predicting the drawing power of these shopping centers, factors besides mass were found to be useful. These include square
footage of shopping goods, stores, and number of parking places. 相似文献
44.
45.
Cees P. Middendorp 《Quality and Quantity》1991,25(3):235-252
An attempt is made to bridge the gap between the theorists and modellists approaches to the conceptualization of theoretical constructs. The former approach assumes that every theoretical construct has a surplus meaning over and above its operationalization and measurement as a concept. The latter approach denies this: it only accepts theoretical constructs as functions of relations between observations, i.e. measured concepts.This gap can be bridged by explicating the definition of a theoretical construct before making attempts to operationalize and measure it. An explicated definition should cover all relevant aspects (or: facets) of a construct, systematically brought together in an ideal type model. On this basis, operationalization of the construct can be directly linked to model elements, so that any possibly remaining surplus value is made explicit. The distance between theoretical construct and the measured concept can then be made as small as seems feasible; in principle, the distance can be made zero. The manner in which conservative ideology is conceptualized in a longitudinal research project in the Dutch electorate is presented as an example of this strategy. 相似文献
46.
P. Kennedy 《Empirical Economics》1991,16(4):401-415
This paper extends the mixed estimation technique to handle a case in which the coefficients of a set of linear constraints are known nonlinear functions of an unknown parameter vector for which an extraneous unbiased estimate is available. This novel form of the mixed estimation technique is illustrated by applying it to the Bass innovation/diffusion model of new product growth. It is suggested that this is superior to the traditional method whereby managerial intuition is incorporated into this type of model, and is an attractive alternative to recently-suggested Bayesian methods.I thank an anonymous referee for helpful comments and references. 相似文献
47.
Blake PB 《Hospital materiel management quarterly》1990,12(2):1-8
As a result of the productivity study in both areas, the following objectives can be attained: Ascertain the number of FTEs necessary for staffing requirements. Determine the efficiency level in daily production of trays and sets. Develop standards to measure the overall effectiveness in delivering service. Although this represents a quantitative analysis of the productivity within a CSS department, it is important not to forget the human element in the relationship between CSS and OR employees. 相似文献
48.
49.
In summary, changes came slowly at first in the OR. The biggest inventory reduction came about a year after the effort had begun. It would seem that tackling obsolescence, standardizing products, etc. would give an initial "big chunk" savings, with small amounts coming later as inventories are lowered. What we expected did not occur, due to the inherent nature of practices and what was customarily being used. For example, previously, some equipment purchases were paid for by purchasing product, which resulted in long-term commitments and high supply costs. The OR at times seemed more like a process of managing change, not just supplies. FOCUS is a daily process. How many times can you afford to overlook this process? How often are the mistakes of the past repeated? In review, we suggest this simple outline: Follow-through (review each case from start to finish), Obsolescence (schedule inventories every six months), Control (achieve inventory management by adjusting PAR levels to needs), Utilization (utilize product/equipment with your control), and Standardization (standardize products and measure results). 相似文献
50.
P. Gigante 《Decisions in Economics and Finance》1990,13(1-2):147-161
Viene studiato il problema della determinazione della strategia riassicurativa ottima in caso di riassicurazione individuale proporzionale, secondo l'approccio media-varianza. In particolare si analizzano alcuni modelli semplificati nei quali si raggruppano le polizze di un portafoglio sulla base di certe caratteristiche di omogeneità; ciò consente di ridurre in maniera sensibile la complessità dei calcoli previsti nella procedura generale. Completano il lavoro considerazioni di carattere operativo.
Summary The optimal reinsurance strategy for the proportional reinsurance problem in a meanvariance framework is investigated. In order to simplify the algorithmic complexity, simple models based on the aggregation of portfolio policies are studied. Some operational remarks are added.相似文献