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991.
992.
D.W. Daniel 《Omega》1980,8(4):409-419
A closed game is described in which one person, representing a land force commander, plays against an unknown but pre-determined threat and decides when and where to deploy reserves. The game was designed to investigate the value of various levels of intelligence data. But large changes in data have had little effect on the quality of decisions made; the dominant feature is the variation between players. The possibility that the game itself might add unnecessarily to this variation has been examined. Accepting that large variation between players may be a fact of life, a way of increasing the efficiency of highly controlled games has also been tested. A number of working hypotheses, thought to be independent of the defence context, are offered to future game designers and the question is raised as to why Operational Researchers, who claim to assist decision-taking, know so little about what influences a decision.  相似文献   
993.
994.
Time series analysis of fertility can improve demographic forecasts. The optimal forecast and its variance for births to an age-structured population subject to serially correlated random fertility are developed. The general case in which the fertility process had arbitrary autoregressive structure is dealt with and then the 4 special cases of white noise, 1st-order autoregressive, 2nd-order autoregressive, and random walk are considered. Consequently, it is determined that the predictions and their variances are highly sensitive to the autoregressive structure of fertility and, therefore, if stochastic models are to be used for prediction, they must emphasize this aspect of the problem. Preliminary empirical efforts to model the time series of U.S. fertility from 1917 to 1972 proved unsuccessful, but it is obvious that at least a 2nd-order autoregressive scheme is require d. The analysis proveded should be helpful in: 1) any application of the procedures requires a successful parameterization of the fertility process; 2) fertility variations could be decomposed into the effects of nuptiality and marital fertility and then births and marriages could be jointly predicted; and 3) the simplifying approximations should be dropped and each age-specific rate could be analyzed and predicted.  相似文献   
995.
In an analysis of the validity of popular stereotypes of youthful conflict with adult society, based upon surveys carried out in Melbourne, the attitudes of young people are compared with the attitudes which they impute to their friends, parents and teachers. The results indicate that young people are influenced in their estimate of the friends' attitudes by the popular stereotype of young people which may in turn, influence their own attitudes. This interpretation explains the distribution of responses along the conservative-innovative continuum, except in regard to opposition to de-humanization where the respondents are more likely to attribute innovative responses to themselves than to their friends. Most young people perceive their interpersonal environment to be supportive of their own attitudes.  相似文献   
996.
997.
998.
This note gives and discusses balanced row-and-column designs for experiments with two non-interacting sets of treatments, one set not being applied to all the rows. These designs are potentially useful for occasions when trees that have tested one set of experimental treatments are needed for testing a second set before the residual effects of the first have become negligible, but when the experimenter wishes to apply the second set to only some of the rows. The designs are appropriate if the residual and new effects do not interact.  相似文献   
999.
This study assessed the playgrounds of developmental day care centers and compared them with playgrounds of regular certified day care centers. Twenty playgrounds, randomly selected from the listing of developmental day centers, were compared with a matched sample of 20 playgrounds from certified day care centers in one state. A revision of Frost's Playground Rating System (1978b) was employed to rate the two groups of playgrounds on content, safety, and function. Data were analyzed using an analysis of variance technique. The quality of developmental day center playgrounds for exceptional children was inferior to that of regular day care center playgrounds in terms of playground content. No significant differences were noted on safety or function.  相似文献   
1000.
Several themes in Wirth's “Urbanism as a Way of Life” generate the prediction that alcohol use (versus nonuse) will be more widespread among residents of urban areas. Multiple regression analysis of data from two recent national polls (1966, 1968) reveals support for this prediction. With eight other key sociological variables simultaneously controlled, the greater the urbanism of a community (measured in terms of community size), the greater the proportion of alcohol users it contains. To make certain that this association is due to urban conditions (as opposed to merely the absence of rural forces which encourage abstinence), the effects of rural forces are reduced by omitting the most rural categories of the community size measure of urbanism, and the data are reexamined. The association still persists, basically because of the larger proportion of middle to upper status, white, and Protestant alcohol users in the more urban areas.  相似文献   
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