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991.
This paper is concerned with the right use of simple hypothesis tests in the area of positive accounting research. Both the usefulness and the limitations of the technique are dealt with in detail.  相似文献   
992.
    
The peri-urban fringes of large metropolitan areas of Australia continue to experience major changes as natural and semi-natural landscapes are converted to built-up areas largely through increased residential development. These irreversible conversions are producing significant challenges for ecological and environmental protection. Yet, there has been little attempt to systematically analyse and model some of the key spatial features of these peri-urban fringes, especially in terms of examining factors underpinning new residential development. This paper attempts to fill this information gap using Adelaide, South Australia, as an exploratory case study. Using parcel-level data, we quantified spatial patterns of residential development during four consecutive periods (ten-year intervals between 1971 and 2010), revealing a gradual slow-down in the rate of new housing development after the 1980s. The effects of major roads and services, residents’ attraction to areas of high natural amenity, and previous residential development were estimated using logistic regression models and geographically weighted logistic regression models, respectively. Variation partitioning was used to examine the relative importance of three groups of predictors of residential development. Roads and services had the greatest impact on the pattern of residential development in the 1970s, while previous residential development ranked first among the three groups of forces in the last three time-periods. Influences relating to the attraction of natural amenities were of the least importance to peri-urban residential development during all four periods. These findings can help understand change mechanisms within peri-urban fringes and to develop corresponding policy responses to improve their management.  相似文献   
993.
Alternative crops, combined with modern farming methods, are integral parts of the new agricultural model and dominant priorities of agricultural policy. The new conditions created in the internal and global markets of agricultural products indicate significant opportunities for growing alternative crops and for the introduction of modern farming practices and processing. The present study aims to assess the factors that determine the landholder’s decision to uptake an alternative crop. Primary data were gathered through a quantative survey (in-depth interviews) with landholders in two remote and less-favored prefectures of Northeastern Greece, and were analysed through a logistic regression model. The results indicate that the most significant determinants for adopting an alternative crop involve the scientific support to farmers, the development of product demand in the market, the creation of agricultural cooperatives, the development of promotional campaigns for the alternative products, the education and knowledge regarding alternative crops, and the landholder’s satisfaction with income. On the contrary, negative factors to their decision refer to exports development, product subsidies, landholder’s age, membership to a cooperative in its current form, and satisfaction with pesticides prices. Despite the dominance of conventional agriculture models and varieties, the new favorable investment conditions can spur the promotion of alternative crops.  相似文献   
994.
    
Tea expansion, a typical process of regional land use and cover change (LUCC), has raised great concerns on regional sustainability. In this regard, exploring the determinants of tea expansion should provide critical implications for land use policy. It has been widely recognized that LUCC interacts nonlinearly with a set of determinants and their feedbacks should be rather complex. Policy makers are now facing the challenge to identify, apportion, and compare the determinants of regional tea expansion for designing more targeted political intervenes. Our paper utilizes a robust tool, the random forest (RF) regression in particular, to explore the determinants of tea expansion across two periods (1985–2007 and 2007–2016) in Anji County, a typical region of tea production in subtropical China. More specifically, tea is extracted from Landsat imageries and total tea cultivated area acts as the dependent variable. Exploratory variables include 38 potential determinants and these determinants are divided into two categories (biophysical and socioeconomic) at two levels (pixel and village). We obtain some similar findings, though the relative importance of determinants varies with the two periods. In general, biophysical determinants (e.g., topography, soil type, land use in the neighborhood) present greater relative importance than the socioeconomic determinants in both periods. In period 1985–2007, biophysical determinants at pixel level are more essential in governing tea expansion. In period 2007–2016, the relative importance of pixel level biophysical determinants is comparable with that of the village level determinants. Comparisons of the two periods indicate that relative importance of soil type and socioeconomic proximity becomes greater in period 2007–2016, while that of the total employees and non-agricultural population proportion becomes lower. Partial dependency plots are further drawn to visualize the marginal effect of each determinant. We finally propose three options for land use policy towards sustainability. Our study demonstrates that the RF regression is efficient for policy makers to understand the determinants of tea expansion with a nonlinear and complex nature.  相似文献   
995.
This paper studies estimation of average economic growth in time series models with persistency. In particular, a joint estimation of the trend coefficient and the autoregressive parameter is considered. An analysis on the proposed estimator is provided. Our analysis is also extended to the case with general disturbance distributions. A nonlinear M estimator and a class of partially adaptive M estimators which adapt themselves with respect to a measure of the tailthickness are considered. The joint estimator and its partially adapted version are compared with several conventional estimators. Monte Carlo experiments indicate that the proposed estimators have good finite sample performance. We use the proposed estimation procedure to estimate the growth rates for real GNP and consumer price index in 40 countries.  相似文献   
996.
    
Informal paratransit operators using a range of vehicle types (including pickup trucks, small buses, and motorcycles) are a major provider of mobility in rural areas of the developing world. The paper describes a mixed method approach used to examine such operators’ decisions about vehicle deployment, route frequency, network organisation, and pricing in three rural districts in South Africa. New evidence is presented showing that the condition of rural roads (both paved and unpaved) affects the quantity and quality of public transport services provided, as well as the fares charged to passengers. This strengthens the case for judicious infrastructure investment as a way of improving rural access and livelihoods, and suggests how this might happen by way of leveraging better private sector responses. We also describe the emergence of a differentiated service hierarchy involving a variety of vehicle types suited to different operating conditions, and based on intentional coordination among operators of minibus and pickup truck (‘bakkie’) services. We argue that governments should promote such coordination and innovation in rural transport markets.  相似文献   
997.
    
This study evaluates spatial variation in the relationship between agricultural output and input use across Turkey. The potential impact of the national agricultural policy reform introduced in 2001 on the spatial variation in agricultural output elasticities across the country was explored. By applying a spatial production function to the province‐level data in 2000 and 2007, spatial heterogeneity in the variance of provincial total factor productivity and the input factor‐output elasticities was identified across the country. Results show that the disparities in agricultural activities and geographic conditions affected return from input factors. Empirical findings from a spatial spillover model also suggest that changes in the input factor‐output elasticities varied significantly across Turkey between 2000 and 2007, after the policy reform. Results suggest that future policy reform that recognizes regional comparative advantage through understanding the geographic heterogeneity of the agricultural sector is important for enhancing Turkey's agricultural output.  相似文献   
998.
    
Despite several environmental and economic benefits of crop rotation, the adoption of this agricultural practice is relatively low. Understanding the reasons for low adoption is important from a sustainability policy perspective. This study explores the motivation, challenges, and sources of information of agricultural producers who participate in crop rotation practices in South Dakota, North Dakota, and Nebraska. The findings of a mail survey of 672 producers in these three states show that producers are familiar with the crop rotation practice. Economic profitability is found to drive motivation for crop rotation adoption. The results of a binary logistic regression model show that a producer who perceives that crop rotation is beneficial to farm profitability is 1.83 times more likely to adopt it than the producer who does not believe in its profitability to the farm. The lack of time or resources is the primary barrier to the adoption of crop rotation practice. This study provides additional evidence in support of the importance of farm profitability for the adoption of the practice of crop rotation. Understanding the rationale and addressing the challenges faced by agricultural producers would be useful in planning and policy making of sustainable agriculture.  相似文献   
999.
Abstract

Background: More and more disabled elderly need long-term care as China becomes an aging society. In 2016, there were 220 million people over the age of 60, and nearly 10 million completely disabled elderly people who cannot complete Activities of Daily Living (ADLs). Therefore, the topic of influencing factors for disability among the elderly in China has attracted close attention from researchers, most of which use the traditional empirical methods, such as Ordinary Least Squares (OLS) and logistic.

Objective: The purpose of this paper was to introduce the Bayesian Quantile Regression (BQR) method to the topic of the disabled elderly, which was achieved by using BQR to study the influencing factors of disability among the elderly in China during 2003–2016.

Methods: This paper was the first attempt to use the BQR for the influencing factors of disability among the elderly in China. Furthermore, a comparison was made between the regression results of BQR, OLS, Quantile Regression (QR), and Bayesian Linear Regression (BLR).

Results: It was found that there was a relatively stable relationship between chronic diseases and disability, although there was a little difference in different quantiles. In addition, the BQR can obtain results similar to the traditional method. For instance, the coefficient of chronic diseases (to total disability) obtained by OLS, QR, and BLR were basically consistent (around 0.778), which was similar to BQR. The BQR not only provided estimates for all the quantiles, but also provided upper and lower values of a certain confidence interval.

Conclusions: By applying the BQR to the influencing factors of disability among the elderly in China, we reached the conclusion that BQR methods are adaptable for this research topic because of their characteristics and advantages over the traditional methods, such as less strict constraints, the estimates for all quantiles, and the combination of historical information with prior information. Moreover, the BQR method appropriately obtained the lower and upper values in a confidence interval, which can provide prediction space for the future.  相似文献   
1000.
Empirical evidence has shown that returns to English language ability are substantial in India. Research has also focused on the impact of private tutoring in the context of developing economies to find evidence that remedial teaching leads to better student achievement and higher test scores. In this paper I analyze whether private tutoring helps in developing English language ability. Simple OLS estimates suggest statistically significant effects but estimated coefficients are rather small at 0.2 percentage points. Presence of confounders and selection bias may potentially understate the true effects of private tutoring on English language ability. To address this issue, I exploit a unique policy experiment in India in a regression discontinuity framework to identify cohorts eligible for private tutoring and compare their outcomes to the ineligible. I use this potentially exogenous policy variation as an instrument for private tutoring and find significant increases in English language ability estimated at 16 percentage points which is much larger than the simple OLS effects. Since standard academic curriculum is not directed towards improving foreign language ability, private tutoring as an input in the education production function seems to offer high marginal returns. From a policy perspective, this implies that private tutoring should be encouraged for enhancing English ability even though there are concerns that this provides disincentives for teachers to teach in school.  相似文献   
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