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131.
Healthy life expectancies are almost always calculated by using health data from cross-sectional surveys. This type of calculation is done partly because data from longitudinal surveys are not always available, and when they are available, they are collected at intervals that are longer than one year. In such cases, collecting health information retrospectively for the years skipped by the survey is useful. The main purpose of this paper is to show how retrospective health information can be used to estimate life expectancies in different health states. Healthy life expectancies are estimated with and without using data on retrospective health information, and the corresponding estimates are compared. The two sets of estimates are similar. We conclude that retrospectively assessed health information based on a one-year recall period can be used to estimate years of life in various health states and that estimates based on such information will closely approximate estimates based on concurrent health information. 相似文献
132.
Myron P. Gutmann Kristine Witkowski Corey Colyer JoAnne McFarland O’Rourke James McNally 《Population research and policy review》2008,27(6):639-665
Spatially explicit data pose a series of opportunities and challenges for all the actors involved in providing data for long-term
preservation and secondary analysis—the data producer, the data archive, and the data user. We report on opportunities and
challenges for each of the three players, and then turn to a summary of current thinking about how best to prepare, archive,
disseminate, and make use of social science data that have spatially explicit identification. The core issue that runs through
the paper is the risk of the disclosure of the identity of respondents. If we know where they live, where they work, or where
they own property, it is possible to find out who they are. Those involved in collecting, archiving, and using data need to
be aware of the risks of disclosure and become familiar with best practices to avoid disclosures that will be harmful to respondents.
相似文献
Myron P. GutmannEmail: |
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134.
James Mahoney Celso M.Villegas 《浙江社会科学》2008,30(3):12-19
本文讨论了比较政治学中历史研究的主要分析方法.第一类是因果分析法,包括横截面分析法和样本内分析法.第二类是时序分析法,包括对路径依赖和发展顺序的分析.本文认为,历史分析与众不同的分析方法使它成为比较政治研究中有力的分析工具. 相似文献
135.
The rise in human life expectancy has involved declines in intrinsic and extrinsic mortality processes associated, respectively, with senescence and environmental challenges. To better understand the factors driving this rise, we apply a two-process vitality model to data from the Human Mortality Database. Model parameters yield intrinsic and extrinsic cumulative survival curves from which we derive intrinsic and extrinsic expected life spans (ELS). Intrinsic ELS, a measure of longevity acted on by intrinsic, physiological factors, changed slowly over two centuries and then entered a second phase of increasing longevity ostensibly brought on by improvements in old-age death reduction technologies and cumulative health behaviors throughout life. The model partitions the majority of the increase in life expectancy before 1950 to increasing extrinsic ELS driven by reductions in environmental, event-based health challenges in both childhood and adulthood. In the post-1950 era, the extrinsic ELS of females appears to be converging to the intrinsic ELS, whereas the extrinsic ELS of males is approximately 20 years lower than the intrinsic ELS. 相似文献
136.
Certain motor vehicle safety standards stipulate a collision test speed and a set of performance criteria that vehicles must satisfy during or after the collision test. For example, Federal Motor Vehicle Safety Standard 301 requires a 30 mile per hour (mph) barrier collision and specifies a certain maximum allowable limit on the total spillage of fuel. Vehicle designs are required to meet this standard; however, when collision tests are conducted at speeds higher than the standard, vehicles do not always satisfy the performance criteria. This paper develops a mathematical model for estimating the probability of meeting the standard by using a Bayesian framework to incorporate engineering judgment with collision test results. The model is based on the idea that there are random features to a vehicle's ability to meet performance standards in a collision, especially at such elevated speeds. Example calculations are included to illustrate the estimation of the probability of meeting the standard and to compare it with a maximum likelihood approach. 相似文献
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139.
Infants often protest the activities of their caregivers, and this particular social interaction may provide an important window on early communication and its development. This study used naturalistic methods to investigate the development of vocal protests. Fifteen mother‐infant dyads at each of 5 ages, from 3 to 18 months, were observed at home. Maternal behaviors of caregiving and prohibiting were tallied from videotapes, as were infants' protests of these behaviors. Maternal caregiving decreased with age, but maternal prohibitions increased. There were no changes over age in the probability of protesting maternal caregiving behavior; however, 12‐month‐olds were more likely to protest prohibitions than 6‐ or 8‐month‐olds. Older infants were also more likely to use intense protests, such as screams, than younger infants. These age‐related changes were mirrored by the differences in prohibitions and protests observed between 8‐month‐olds who could crawl and those who could not. Findings from this study were related to previous research on infant crying as an important part of the prelinguistic communication system. 相似文献
140.
Infants' Processing of Featural and Configural Information in the Upper and Lower Halves of the Face
Three‐ to 4‐month‐old and 6‐ to 7‐month‐old infants were administered an infant version of the Face Dimensions Test that has been used with adults (e.g., Bukach, Le Grand, Kaiser, Bub, & Tanaka, 2008). Infants were familiarized with a photograph of a woman's face and then tested with the familiar face paired with a face differing in the (a) distance separating the eyes (a configural/eyes change), (b) distance between the nose and mouth (configural/mouth change), (c) size of the eyes (featural/eyes change), and (d) size of the mouth (featural/mouth change). Infants were shown to be more sensitive to (a) configural than featural change, and (b) change around the eyes versus the mouth. Implications for the development of face processing are discussed. 相似文献