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101.
This paper is intended to assist professors, administrators, librarians and other members of university level committees that must consider research expectations and research quality in academic fields that they lack. While this is not a problem for field experts, it is a difficulty when people are asked to make decisions in areas of study other than their own. This is commonly the case for senior university professors, librarians and administrators in regards to university wide decisions. The paper investigates this gap, through a study of 27 academic fields in 348 highly regarded universities. We find that there are almost always statistically significant differences in activity between academic fields, regardless of the metric one considers. However, it is possible to understand these differences by comparing the distribution of a known academic field to that of a field that one is not familiar with. Tables and information are provided to assist in the comparison of different fields of study on metrics such as: departmental publications and researcher level metrics of publications, citations, H-index, and total number of co-authors. The information can also be used to support decisions associated with promotion to senior posts such as endowed chairs and professorships. Information regarding specific universities and researchers are included in the data supplement. 相似文献
102.
How peer groups contribute to educational outcomes has long interested researchers. However, the possibility that peer groups dominated by either low- or high-achieving youth can have substantively different effects on achievement has been largely ignored. In this paper, we show that while being embedded in a high-achieving network of friends is not associated with increased own achievement, being embedded in a low-achieving network is associated with decreased own achievement. In additional analyses, we present evidence that these associations are at least in part due to influence, as opposed to only selection effects or shared environment. We also examine whether the structure of the network in which a student is embedded might affect their educational achievement. We show that achieving at higher levels positively predicts how centrally located a student is in their network, but being more centrally located does not predict concurrent achievement. This finding suggests that the behavior of individuals is affecting the formation of network structure and not the reverse. 相似文献
103.
Many important decisions involve financial risk, and substantial evidence suggests that women tend to be more risk averse
than men. We explore a potential biological basis of risk-taking variation within and between the sexes by studying how the
ratio between the length of the second and fourth fingers (2D:4D) predicts risk-taking. A smaller 2D:4D ratio has been linked
to higher exposure to prenatal testosterone relative to estradiol, with men having lower ratios than women. In financially
motivated decision-making tasks, we find that men and women with smaller 2D:4D ratios chose significantly riskier options.
We further find that the ratio partially explains the variation in risk-taking between the sexes. Moreover, for men and women
at the extremes of the digit-ratio distribution the difference in risk-taking disappears. Thus, the 2D:4D ratio partially
explains variation in financial risk-taking behavior within and between sexes and offers evidence of a biological basis for
risk-taking behavior. 相似文献
104.
Robert H. Zieger 《Social history》2013,38(3):339-342
P. J. Cain and A. G. Hopkins, British Imperialism: Innovation and Expansion, 1688–1914 (1993), xiv + 490; British Imperialism: Crisis and Deconstruction, 1914–1990 (1993), xiii + 326 (Longman, London, £17.99 and £3.99). W. D. Rubinstein, Capitalism, Culture, and Decline in Britain, 1750–1990 (1993), viii + 182 (Routledge, London, £25.00). Stanley Chapman, Merchant Enterprise in Britain: From the Industrial Revolution to World War I (1992), xvi + 336 (Cambridge University Press, Cambridge, £40.00). 相似文献
105.
It appears to be common practice with ridge regression to obtain a decomposition of the total sum of squares, and assign degrees of freedom, according to established least squares theory. This discussion notes the obvious fallacies of such an approach, and introduces a decomposition based on orthogonality, and degrees of freedom based on expected mean squares, for non-stochastic k. 相似文献
106.
107.
Robert Schoen 《Mathematical Population Studies》2013,20(3):195-210
Multistate populations with changing rates of interstate transfer are an example of compartment models and depict the experience of persons in distinct but intercommunicating states. Such models can be used in analyses of many demographic phenomena, including migration, labor force participation, and health status. This paper extends present knowledge of the relationships prevailing in such dynamic models by developing procedures that yield closed form expressions relating transfer rates to the state-specific population trajectories that they generate. The focus is on a subset of multistate models that do not recognize age and that have restricted variability in rates of transfer and natural increase. Dynamics in the two state, no-growth case, where the two time-varying transfer rates always sum to a constant value, are analyzed in depth. In specified models with any number of intercommunicating states, sine and cosine fluctuations in the transfer rates are shown to yield sine and cosine fluctuations in the numbers of persons in each state. 相似文献
108.
109.
Kate de Medeiros Robert L. Rubinstein Chiadi U. Onyike Deirdre M. Johnston Alva Baker Matthew McNabney 《Journal of Housing for the Elderly》2013,27(1-2):206-220
We compared data drawn from a random sample of 399 current assisted living residents and a subsample of 222 newly admitted residents for two groups: childless residents and residents with children. The percentage of childless residents (26%) in our study was slightly higher than U.S. population estimates of childless individuals aged 65 years and older (20%). In the overall sample, the two groups differed significantly by age, race, and women's years of education. The childless group was slightly younger, had a higher percentage of African American residents, and had more years of education than the group with children. In the subsample, we looked at demographic, functional, financial, and social characteristics and found that childless residents reported fewer diagnoses of dementia and fewer visits from a relative but more reported paying less money per month for assisted living and having private insurance than residents with children. As childlessness among older adults continues to increase, it will become increasingly important to understand how child status affects the need for and experience of long-term care. 相似文献
110.