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861.
L T Farrell 《Child welfare》1988,67(5):462-468
Out of concern about the underreporting of father-daughter incest, the author has conducted a study in Virginia to test certain observations in the literature about the relatively small number of cases that come to light voluntarily. The findings point clearly to contributory case characteristics that can sensitize practitioners to the possibility of undisclosed incest. 相似文献
862.
A number of results have been derived recently concerning the influence of individual observations in a principal component analysis. Some of these results, particularly those based on the correlation matrix, are applied to data consisting of seven anatomical measurements on students. The data have a correlation structure which is fairly typical of many found in allometry. This case study shows that theoretical influence functions often provide good estimates of the actual changes observed when individual observations are deleted from a principal component analysis. Different observations may be influential for different aspects of the principal component analysis (coefficients, variances and scores of principal components); these differences, and the distinction between outlying and influential observations are discussed in the context of the case study. A number of other complications, such as switching and rotation of principal components when an observation is deleted, are also illustrated. 相似文献
863.
864.
The relationship between the infestation rate of carambola fruits byBactrocera carambolae Drew and Hancock was investigated in a carambola orchard. Phenology of the fruits was found to influence percentage infestation
of fruits byB. carambolae. The proportion of unbagged or susceptible fruits infested varied with time of year and tended to decrease with the increase
of unbagged fruits available on the tree. The number of ovipunctures per fruit varied with fruit size and was also found to
be indicative of the number of adult insects (B. carambolae and parasitoids) that will emerge from each fruit. Higher number of susceptible fruits available on each tree also decreased
both the number of ovipunctures per fruit and the number of eggs laid per fruit, which could possibly be due to the strategy
of spreading the risk adopted by the femaleB. carambolae or a result of random selection with more hosts available. The main parasitoids recorded wereBiosteres vandenboschi (Fullaway) andB. arisanus (Sonan). The mean percentage of parasitism was 38.3% and it followed roughly that of infestation of fruits. 相似文献
865.
For a moderate or large number of regression coefficients, shrinkage estimates towards an overall mean are obtained by Bayes and empirical Bayes methods. For a special case, the Bayes and empirical Bayes shrinking weights are shown to be asymptotically equivalent as the amount of shrinkage goes to zero. Based on comparisons between Bayes and empirical Bayes solutions, a modification of the empirical Bayes shrinking weights designed to guard against unreasonable overshrinking is suggested. A numerical example is given. 相似文献
866.
John T. Addison 《Journal of Labor Research》1982,3(3):335-348
This paper charts the evolution of incomes policy in Finland. Especial emphasis is placed on the constraints on incomes policy
that have operated here, as indeed in other Nordic countries, ultimately to curb the corporatist experiment. 相似文献
867.
868.
Abstract The Bills of Mortality for London were instituted at least as early as 1528 but only a few figures survive before the extant annual series that begins in 1603. Ages at death, even in broad groups of ages, are not generally available until 1728, which is more than 50 years too late to give us any inkling of the ages, if any, at which people were specially susceptible to plague. There are reports, it is true, that suggest that children suffered from plague more severely than adults, at least on certain occasions (as in 1361 or 1418 for example), but nothing more precise. The legend of the Pied Piper of Hamelin may be a folk-memory of a plague (possibly in 1284) that killed mainly the children of the town, for the connection between infestation of rats and the loss of children suggests some kind of plague outbreak. Pollitzer concludes that no particular age group is specially liable to plague, and attributes all differences observed to different risks of exposure. The determinants of the severity of an outbreak would therefore be the environmental details and social customs. 相似文献
869.
870.
Learning about radon's risk 总被引:1,自引:1,他引:0
V. Kerry Smith William H. Desvousges Ann Fisher F. Reed Johnson 《Journal of Risk and Uncertainty》1988,1(2):233-258
This article reports the results of an evaluation of the effectiveness of different types of information materials in communicating the risk from exposure to radon, a naturally occurring indoor air pollutant. The study involved a panel of 2300 homeowners who actually experienced risks from radon, and the information program used to explain these risks. The analysis considered information transfer and performance on specific tasks requiring information on the risk from radon to measure learning. The results suggest a systematic learning process, but indicate that the process can be influenced by how risk information is presented. 相似文献