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901.
902.
Services designed to assist job seekers to leave public assistance and gain employment are well established throughout the U.S. Many of these programs are created and delivered by professionals of higher socioeconomic class backgrounds, but many program participants are of lower social class status. This situation can create “cross‐class” difficulties in the design and delivery of effective job‐search services. The author argues that using a person‐centered perspective, with the deliberate inclusion of genuineness and empathy in all phases of programming, may neutralize cross‐class variables and increase the effectiveness of interventions. Examples from programs emphasizing person‐centered concepts are offered.  相似文献   
903.
An imputation procedure is a procedure by which each missing value in a data set is replaced (imputed) by an observed value using a predetermined resampling procedure. The distribution of a statistic computed from a data set consisting of observed and imputed values, called a completed data set, is affecwd by the imputation procedure used. In a Monte Carlo experiment, three imputation procedures are compared with respect to the empirical behavior of the goodness-of- fit chi-square statistic computed from a completed data set. The results show that each imputation procedure affects the distribution of the goodness-of-fit chi-square statistic in 3. different manner. However, when the empirical behavior of the goodness-of-fit chi-square statistic is compared u, its appropriate asymptotic distribution, there are no substantial differences between these imputation procedures.  相似文献   
904.
The current study examines whether the relation between mothers' responses to their children's negative emotions and teachers' reports of children's academic performance and social‐emotional competence are similar or different for European‐American and African‐American families. Two hundred mothers (137 European‐American, 63 African‐American) reported on their responses to their five‐year‐old children's negative emotions and 150 kindergarten teachers reported on these children's current academic standing and skillfulness with peers. Problem‐focused responses to children's negative emotions, which have traditionally been considered a supportive response, were positively associated with children's school competence for European‐American children, but expressive encouragement, another response considered supportive, was negatively associated with children's competence for African‐American children. The findings highlight the need to examine parental socialization practices from a culturally specific lens.  相似文献   
905.
Incomplete moments are used to characterize income inequality and provide the basis for interdistributional Lorenz curves. Four measures of interdistributional inequality are considered and seen to be related to an interdistributional welfare interpretation. Based upon these measures, there has been a significant secular decline in interdistributional inequality between blacks and whites over the past 30 years.  相似文献   
906.
Book review     
W.G.Cochran: Sampling Techniques, 3rd. Ed. John Wiley & Sons, New York-Santa Barbara-London-Sydney-Toronto 1977. 428 S., £ 12.50; $21.50.

H.Toutenburg: Vorhersage in linearen Modellen. Akademie-Verlag, Berlin 1975, VIII, 176b S., 3 Tab., 28,– M.

O.Kallenberg: Random Measure. Akademie-Verlag, Berlin 1975; Academic Press, London 1976. 104 pp., 28,– M.  相似文献   
907.
This paper considers a likelihood ratio test for testing hypotheses defined by non-oblique closed convex cones, satisfying the so called iteration projection property, in a set of k normal means. We obtain the critical values of the test using the Chi-Bar-Squared distribution. The obtuse cones are introduced as a particular class of cones which are non-oblique with every one of their faces. Examples with the simple tree order cone and the total order cone are given to illustrate the results.  相似文献   
908.
Optimality of experimental designs for spatially correlated observations is investigated.come two dimensional correlation structures are discussed and an attempt has been made to find optimal or nearly optimal design for each sitution.The solution lend to designs similar to that used for repeated measurements.The relative efficiency of the proposed designs in comparison to randomized latin square designs is tabulated for some cases.  相似文献   
909.
Sub-national and cross-national variations in the age difference between spouses are investigated with data from the World Fertility Survey relating to 29 developing countries. Substantial variation within and between countries is evident. Analysis suggests that the relative age of prospective spouses is a factor taken into account in the marriage market. Observed variation in the age difference, within and between countries, cannot be explained as the simple by-product of the random matching of independently determined distributions of men's and women's ages at marriage. Certain age differences are avoided, others chosen more frequently. Preferred age differences appear to differ in the societies studied, however, and this variation can be directly interpreted in terms of two sets of factors: kinship structure and women's roles. The analysis also suggests that demographic determinants of the age difference, in particular age constraints on the pool of possible matches, are of less importance in explaining societal variations than are social structural factors.  相似文献   
910.
Response surface methodology is widely used for developing, improving, and optimizing processes in various fields. In this article, we present a method for constructing three-level designs in order to explore and optimize response surfaces combining orthogonal arrays and covering arrays in a particular manner. The produced designs achieve the properties of rotatability, predictive performance and efficiency for the estimation of a second-order model.  相似文献   
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