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991.
This paper asks whether educational mismatches can account for the positive association between education and wage inequality found in the data. We use two different data sources, the European Community Household Panel and the Portuguese Labour Force Survey, and consider several types of mismatch, including overqualification, underqualification and skills mismatch. We test our hypothesis using two different measurement methods, the ‘statistical’ and the ‘subjective’ approach. The results are robust to the different choices and unambiguously show that the positive effect of education on wage inequality is not due to the prevalence of educational mismatches in the labour market.  相似文献   
992.
Adult refugee claimants experience several well‐documented post‐migratory challenges. Little is known about the resettlement process for refugee claimant families with children. This study reports on 75 open‐ended, in‐depth interviews with refugee claimant families in Montreal about their resettlement challenges and their proposed solutions to them. These interviews were conducted with 33 dyads and triads of children and parents attending a paediatric hospital. Experiences accessing formal and informal child care in Montreal were addressed. Subsequently, a comparative policy analysis was conducted on residency eligibility criteria for child care subsidization. Twenty‐eight out of 39 parents (73%) report a lack of informal or formal child care and 15 out of 33 families (39%) propose improving access to formal child care services. They describe a lack of informal child care as a result of reduced social networks, and affordability as a barrier to formal child care services. Refugee claimants are not eligible for subsidized child care in Quebec. A comparative policy analysis within Canada and comparable countries reveals that this situation is not unique to Quebec. However, most provinces and European countries offer child care subsidies to refugee claimants. Refugee claimants should qualify for child care subsidies. Social workers and community organizations should consider their clients' child care needs in designing programmes and services.  相似文献   
993.
Several estimators for estimating the mean of a principal variable are proposed based on double sampling for stratification (DSS) and multivariate auxiliary information. The general properties of the proposed estimators are studied, search for optimum estimators is made and the proposed estimators are compared with the corresponding estimators based on unstratified double sampling (USDS).  相似文献   
994.

From the available literature, there seems to be no defined approach to resource smoothing exercise except those attempted by Weist (1967, Management Science, 13, B359-B377) and Burgess and Killebrew (1962, Journal of Industrial Engineering, 13, 76-83). The aim of the smoothing exercise is to achieve optimal resource usage by avoiding high peaks and deep valleys in the project resource profile. The general approach has always been to move some activities with floats in the high peak regions to be started at a later date, and as this is done, the valleys will be filled to smooth the resource profile subject of course to time constraint. If this approach is followed as it is, it would be difficult to determine optimality especially when many resources are involved. A cost minimization approach is envisaged in the present study with no limitation on the number of resource inputs. In a situation where the resources are assumed to have the same value, the cost assigned to each of them should be similar. The method follows the general concept but with a difference; cost of the activity in question is considered. The exercise is continued until all the floats are exhausted. The optimum result would then be the one with the minimum cost profile. From examples used for the evaluation, the results obtained are comparable to those of the above two researchers, and some with better results in the majority of cases.  相似文献   
995.
Certain recurrence relations for the moments of different orders of the largest order statistic from a gamma distribution with shape parameter p are obtained. By using this it is shown that for obtaining the moment of any order of each order statistic of a sample of size n from the gamma distribution, one has to evaluate at most n-2 single integrals.  相似文献   
996.
Previous research found that survey response rates were influenced by physical characteristics of the interviewer. However, the effect of hair color on compliance to a survey request has never been studied. Female confederates wearing blond, brown, black, or red wigs solicited 1,200 male and female pedestrians for a survey. It was found those male passersby, but not the female, agreed more frequently to the confederates wearing blond wigs whereas they agreed less to the same confederates wearing red wigs. Greater youth and healthiness associated with blond hair in women is used to explain these results. The practical interest in face-to-face surveys is addressed.  相似文献   
997.
The objective of this study was to evaluate the shape of anterior–posterior curvatures of the spine and to determine the values of body symmetry deviations in the frontal plane, in elderly males. The study group consisted of 34 males aged between 61 and 83 years, attending two hour-long training sessions a week. The comparative group consisted of 30 students. The photogrammetric method based on the Moire phenomenon was used to evaluate the body posture. The obtained data confirm characteristic tendencies of physiological spinal curvatures to change with the aging process. A decrease of the lumbar–sacral spinal-segment inclination and an increase of the upper thoracic spinal-segment inclination were observed in the elderly males. Whereas, the value of thoracic kyphosis lower-segment inclination was similar to the value obtained in young adult males. The stated differences indicate a flattening of lumbar lordosis and a deepening of the upper arch of thoracic kyphosis, which results in a characteristic body posture in the standing position with the head protruding and the upper trunk segment inclined. The above-mentioned observations indicate a dominance of the angular thoracic kyphosis value over the remaining spinal curvatures. These differences occur to a greater degree in elderly males.  相似文献   
998.
Abstract

Twenty-seven University of Rochester students developed clinical manifestations of rubella during 1976–77. Twenty-five were male and had not been immunized against this disease; 18 required infirmary care costing $4,876. On the basis of data for freshman males, a cost analysis demonstrates the feasibility of changing the university policy which encourages immunization only of females to encouragement of either selective or mass immunization of all males as well. Immunization during childhood with combined MMR vaccine is least expensive and should be encouraged. In certain circumstances, selective immunization of susceptible males may be less expensive than the present selective policy, which leaves males at risk.  相似文献   
999.
ABSTRACT

It is time for action by leaders across higher education to strengthen quality improvement (QI) in college health, in pursuit of better care, better health, and increased value – goals closely linked to students' learning and success. The size and importance of the college student population; the connections between wellbeing, and therefore QI, and student success; the need for improved standards and greater accountability; and the positive contributions of QI to employee satisfaction and professionalism all warrant a widespread commitment to building greater capacity and capability for QI in college health. This report aims to inspire, motivate, and challenge college health professionals and their colleagues, campus leaders, and national entities to take both immediate and sustainable steps to bring QI to the forefront of college health practice – and, by doing so, to elevate care, health, and value of college health as a key pathway to advancing student success.  相似文献   
1000.
In this paper, an alternative method for the comparison of two diagnostic systems based on receiver operating characteristic (ROC) curves is presented. ROC curve analysis is often used as a statistical tool for the evaluation of diagnostic systems. However, in general, the comparison of ROC curves is not straightforward, in particular, when they cross each other. A similar difficulty is also observed in the multi-objective optimization field where sets of solutions defining fronts must be compared with a multi-dimensional space. Thus, the proposed methodology is based on a procedure used to compare the performance of distinct multi-objective optimization algorithms. In general, methods based on the area under the ROC curves are not sensitive to the existence of crossing points between the curves. The new approach can deal with this situation and also allows the comparison of partial portions of ROC curves according to particular values of sensitivity and specificity of practical interest. Simulations results are presented. For illustration purposes, considering real data from newborns with very low birthweight, the new method was applied in order to discriminate the better index for evaluating the risk of death.  相似文献   
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