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21.
Summary Rufous turtle dove,Streptopelia orientalis, coming to the soybean field entered it from the outer part to eat soybean cotyledons. As a result, the injured plants extended from the outer to inner parts in the field. A model expressing these behaviours was constructed here, by assuming that the amount of food birds can eat in one block determines whether they stay there or move into neighbour block. As the food decrease due to exploitation of them by birds, birds enter into farther parts with the passage of time. The rate of feeding in all visiting birds (an 0 wherea is the rate of feeding per individual andn 0 the number of birds visiting) and the rate of staying at a block,b, was estimated from the field experimental results, using the above model. The value ofan 0 fluctuated greatly, depending upon the season in which soybean seeds sowed. The value ofb also fluctuated inversely with that ofan 0, suggesting the the staying rate decreases with an increase in the number of doves coming, probably because of interference among individuals.  相似文献   
22.
Despite longstanding interest in cultural differences in emblems, there have only been a few systematic investigations of those differences, and to date there is no study that catalogues and compares emblems across different cultural groups to a standard list of verbal messages. This study does so. Encoders from six world regions produced potential emblems from a standard verbal message list. Gestures that were encoded by at least 70% of the encoders in a region were shown to observers from the same regions, and gestures that were judged correctly as the message intended by at least 70% of the decoders in that region were considered emblems. These procedures resulted in the cataloguing of cultural differences in emblems to the same verbal message list. Surprisingly, the results also indicated a small group of emblems that were similarly encoded and decoded across cultures.  相似文献   
23.
Since the extensive work by Burns and Mitchell, many economists have interpreted economic fluctuations in terms of business-cycle phases. Given this, we argue that, in addition to usual model-selection criteria currently used in the profession, the adequacy of a univariate macroeconomic time series model should be based on its ability to replicate two important business-cycle features of the U.S. data—duration and amplitude. We propose several checks for whether univariate statistical models generate business-cycle features observed in U.S. gross domestic product (GDP) and find that many popular nonlinear models for the log of real GDP are no better at replicating the duration and amplitude features of the data than a simple ARIMA(1, 1, 0).  相似文献   
24.
    
Summary AsMatsumoto andHuffaker (1973) concluded that their initial universe size was too small for the proper separation of the effects of host density and dispersion on parasite performance, a larger universe of 38 1/2″ (length) ×38 1/2″ (width) ×3″ (height) was used. When individual parasites were exposed to fixed densities and dispersion patterns of host, they displayed an overall decrease in the parasitization rate when compared to the small universe. In all cases aHolling-type response resulted. When a group of 10 parasites per test was employed a Nicholsonian type of response resulted. In an experimentally confined space, the parasites displayed a mutual behavioral interference resulting in emigration which accelerated as the parasite density increased. These studies were conducted as a partial fulfillment in the Ph. D. program of one of us (B. M. Matsumoto) and is a part of a broad investigation into the processes operating in the dynamics of arthropod populations under grants toC. B. Huffaker from the U. S. Public Health Service, National Institutes of Health and the U. S. Department of Agriculture.  相似文献   
25.
In this article, we report the development of a new test designed to measure individual differences in emotion recognition ability (ERA), five studies examining the reliability and validity of the scores produced using this test, and the first evidence for a correlation between ERA measured by a standardized test and personality. Utilizing Matsumoto and Ekman's (1988) Japanese and Caucasian Facial Expressions of Emotion (JACFEE) and Neutral Faces (JACNeuF), we call this measure the Japanese and Caucasian Brief Affect Recognition Test (JACBART). The JACBART improves on previous measures of ERA by (1) using expressions that have substantial validity and reliability data associated with them, (2) including posers of two visibly different races (3) balanced across seven universal emotions (4) with equal distribution of poser race and sex across emotions (5) in a format that eliminates afterimages associated with fast exposures. Scores derived using the JACBART are reliable, and three studies demonstrated a correlation between ERA and the personality constructs of Openness and Conscientiousness, while one study reports a correlation with Extraversion and Neuroticism.  相似文献   
26.
This note considers a method for estimating regression parameters from the data containing measurement errors using some natural estimates of the unobserved explanatory variables. It is shown that the resulting estimator is consistent not only in the usual linear regression model but also in the probit model and regression models with censoship or truncation. However, it fails to be consistent in nonlinear regression models except for special cases.  相似文献   
27.
Abstract: At present, Japanese researchers conducting social surveys encounter several difficulties such as restricted access to official registers and a decrease in current response rates. These researchers may expect these difficulties to be solved by the survey techniques or methods developed outside Japan, such as computer-assisted interviews (CAI) and Internet surveys. It is unclear whether the numerous technical differences between survey methodologies developed in Japan and elsewhere imply the backward-ness of Japan or cultural differences. This paper discusses the potential of various recent survey methods, focusing on the culture and paradigms in Japan and the UnitedStates. First, this paper presents an overview of survey techniques, such as computer-assisted personal interviewing, Internet surveys, and mixed modes. Second, it points out the fact that the existence of the registers and different survey concepts might have created the different survey paradigms. In addition, reference is made to the linguisticdifferences between the US and Japan. The results indicate that survey research is more dispersed in Japan than in the US and that survey research adapted to the uniqueness of Japanese culture is not accumulated sufficiently, although such an accumulation is required. Finally, it is stated that not only surveys, but also the concept of methodology, is not very popular in Japan. Furthermore, the development of survey research in the US is likely to be related to pragmatism.  相似文献   
28.
The authors examined the relationship between strength-training behavior and perceived environment in older Japanese adults. An Internet-based survey was conducted of 293 adults age 68.2 ± 2.8 yr. The dependent variable was regular strength-training behavior. The IPAQ environment module, access to facilities for strength training, and home equipment for strength training were environmental factors. Logistic-regression analysis was employed. After demographic variables (gender, age, educational background, household income, body-mass index, self-rated health status, smoking habit, and residential area) were adjusted for, home equipment for strength training (OR = 2.14, 95% CI = 1.50-3.06), access to facilities for strength training (OR = 2.53, 95% CI = 1.32-4.85), and observing active people (OR = 2.20, 95% CI = 1.06-4.58) were positively correlated with regular strength-training behavior. In conclusion, environmental factors associated with strength-training behavior were access to facilities for strength training, having home equipment for strength training, and observing active people.  相似文献   
29.
Summary A statistical and graphic study is presented of the wastage of eggs byVenturia (=Nemeritis) canescens when searching singly and in groups of 10 among hosts at four different host densities in laboratory universes as described byHuffaker andMatsumoto (preceding paper of this journal). The host insect was the fluour mothAnagasta kühniella and the host densities used were 10, 30, 100 and 200 per universe. Intensity of egg wastage due to superparasitim varied significantly according to host density, and between the two parasite densities employed, 1 and 10, using bothF-tests and chi-square tests. Plots ofk-factor analysis on this egg wastage showed high negative correlations with host density, and the raw data for single parasites was well represented by a parabola while that for the grouped parasites departed from this relationship only at the lowest host density. These studies were conducted as a part of a general investigation into the processes operating in the population dynamics of arthropods under grants from the National Institutes of Health, U. S. Public Health Service (#A10-1611), and the National Science Foundation and Environmental Protection Agency (NSF DEB7504223) to the University of California. The findings, opinions and recommendations expressed herein are those of the authors and not necessarily those of the University of California, the National Institutes of Health, the National Science Foundation or the Environmental Protection Agency.  相似文献   
30.
Saeki  Ikuyo  Niwa  Shigeru  Osada  Noriyuki  Azuma  Wakana  Hiura  Tsutom 《Urban Ecosystems》2020,23(3):603-614

Urbanization generally reduces wildlife populations. Individual species responses, however, are often highly variable, and such variability can be explained by differences in species ecological traits. To examine this hypothesis, we focused on two co-occurring land snails, Ezohelix gainesi and Euhadra brandtii sapporo; the former is ground-dwelling and the latter is arboreal. We first estimated their population densities at nine sites distributed along an urbanization gradient: three were located in continuous natural forests, three at the edge of natural forests, and the rest in small isolated forests in urban areas. As a result, the ground-dwelling E. gainesi occurred at highest density in urban forests, followed by forest edges and continuous forests. By contrast, the arboreal E. b. sapporo occurred at highest density in continuous forests, but declined in forest edges and urban forests. We then conducted manipulative field experiments to quantify changes in predation pressure on these species. Ground-tethered E. gainesi and E. b. sapporo were repeatedly predated upon by forest-living mammals in continuous forests, but their survival rates increased in forest edges and urban forests. By contrast, canopy-tethered E. b. sapporo maintained high survival rates in all three forest types. The results indicate that a lack of mammalian predators enables ground-dwelling species to occur at high densities in urban forests, whereas the arboreal species was not affected by this predator relaxation effect. The combination of species-specific behavioural traits and changes in predator communities across an urbanization gradient has important effects on the biodiversity of urban ecosystems.

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