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801.
Hedayat et al. [1988a. Sampling plans excluding contiguous units. J. Statist. Plann. Inference 19, 159–170; 1988b. Designs in survey sampling avoiding contiguous units. In: Krishnaiah, P.R., Rao, C.R. (Eds.). Handbook of Statistics, vol. 6. Elsevier, Amsterdam, pp. 575–583] first introduced balanced sampling designs for the exclusion of contiguous units. Sampling plans that excluded the selection of contiguous units within a given sample, while maintaining a constant second-order inclusion probability for non-contiguous units, were investigated for finite populations of N units arranged in a circular, one-dimensional ordering. There remain many open questions about the existence of such plans and their extension to plans excluding adjacent units. We present new generation techniques and new balanced sampling plans for the exclusion of adjacent units under finite, one-dimensional, circularly and linearly ordered populations. 相似文献
802.
Mary E. Pharis Ph.D. ABPP Ann Eisler MSSW 《Child and Adolescent Social Work Journal》1990,7(6):461-474
This paper informs clinicians about the nature of childhood meatotomies, and presents two cases which suggest that the presence of a meatotomy in the developmental history of male clients should alert clinicians to the potential significance of particular body damage fears and body integrity issues in the client. 相似文献
803.
G. K. Eagleson & H. G. Müller 《Journal of the Royal Statistical Society. Series B, Statistical methodology》1997,59(1):173-189
We consider whether one should transform to estimate nonparametrically a regression curve sampled from data with a constant coefficient of variation, i.e. with multiplicative errors. Kernel-based smoothing methods are used to provide curve estimates from the data both in the original units and after transformation. Comparisons are based on the mean-squared error (MSE) or mean integrated squared error (MISE), calculated in the original units. Even when the data are generated by the simplest multiplicative error model, the asymptotically optimal MSE (or MISE) is surprisingly not always obtained by smoothing transformed data, but in many cases by directly smoothing the original data. Which method is optimal depends on both the regression curve and the distribution of the errors. Data-based procedures which could be useful in choosing between transforming and not transforming a particular data set are discussed. The results are illustrated on simulated and real data. 相似文献
804.
The goal of this study was to examine children's cognitive and language development and social engagement of mother as mediators of the relationship between maternal emotional availability at 15 months and children's empathy at the ages of two and four. Participants were 661 low-income, ethnically diverse mother-child dyads participating in a trial of home visitation in the Denver area. Using home- and lab-based free-play episodes, mothers' emotional availability (15 months) and children's social engagement of mother (21 and 24 months) were assessed. Standardized measures were used to assess children's language development (21 months) and cognitive development (24 months). Empathy was assessed using a simulated injury paradigm at ages two (both 21 and 24 months) and four. The predictive models supported the hypothesis that the child's cognitive and social resources mediate the relationship between maternal emotional availability and children's empathy with respect to empathy at the age of two toward both mothers and an unfamiliar examiner. These results indicate that parental sensitive behavior is not the only important condition for predicting children's empathy, and that children's own internalized resources are a likely mechanism of transmission from parents caring for their children to children learning to care for others. 相似文献
805.
Robert H. Lyles Cynthia M. Lyles & Douglas J. Taylor 《Journal of the Royal Statistical Society. Series C, Applied statistics》2000,49(4):485-497
Objectives in many longitudinal studies of individuals infected with the human immunodeficiency virus (HIV) include the estimation of population average trajectories of HIV ribonucleic acid (RNA) over time and tests for differences in trajectory across subgroups. Special features that are often inherent in the underlying data include a tendency for some HIV RNA levels to be below an assay detection limit, and for individuals with high initial levels or high ranges of change to drop out of the study early because of illness or death. We develop a likelihood for the observed data that incorporates both of these features. Informative drop-outs are handled by means of an approach previously published by Schluchter. Using data from the HIV Epidemiology Research Study, we implement a maximum likelihood procedure to estimate initial HIV RNA levels and slopes within a population, compare these parameters across subgroups of HIV-infected women and illustrate the importance of appropriate treatment of left censoring and informative drop-outs. We also assess model assumptions and consider the prediction of random intercepts and slopes in this setting. The results suggest that marked bias in estimates of fixed effects, variance components and standard errors in the analysis of HIV RNA data might be avoided by the use of methods like those illustrated. 相似文献
806.
Andrew Worthington Kerry Brown Mary Crawford David Pickernell 《Review of Economics of the Household》2007,5(2):209-221
Regression modeling is used to predict gambling patterns in Australia on the basis of the unit record files underlying the
Australian Bureau of Statistics’ Household Expenditure Survey of 6,892 households. The four largest categories of gambling
expenditure are examined, namely: lottery tickets, lotto-type games and instant lottery (scratch cards), TAB (pari-mutuel
wagering) and related on course betting, and poker (slot) machines and ticket machines. Determining factors analyzed include
the source and level of household income, family composition and structure, welfare status, gender, age, ethnicity and geographic
location. Apart from the determinants of expenditure varying widely across the different types of gambling activity, the results
generally indicate that the source of household income is more important than the level of income and that household composition
and regional location are likewise significant in determining gambling expenditure.
相似文献
807.
Hilde H. Wierda‐Boer Jan R.M. Gerris Ad A. Vermulst 《Journal of marriage and the family》2008,70(4):1004-1014
Using questionnaire data on 149 Dutch dual‐earner couples with young children participating in the European Famwork study, we examine how adaptive strategies and gender ideology relate to parents’ perceived success in balancing work and family. Path analysis indicates that some adaptive strategies may harm individuals’ work‐family balance, particularly when they are made in the domain where the time budget is limited. In the need to succeed in multiple roles, however, endorsement of traits traditionally linked with the opposite gender, that is masculine traits for women and feminine traits for men, seems beneficial. We speculate that two underlying mechanisms — social pressure and time constraints — jointly operate in determining perceived success in balancing work and family. 相似文献
808.
Carol H. Meyer DSW 《Clinical Social Work Journal》1977,5(4):289-292
809.
Ian H. Wilson 《Long Range Planning》1973,6(2):39-42
Without in any way denying that there are forces for stability, I want to state, as strongly as I can, my conviction that change is now more rapid, more complex and more pervasive than ever before in human history. There are forces loose in the world, particularly in the ‘post-industrial society’ of the United States, that go far beyond the youth movement in creating change. As a result, it is utterly unrealistic to pretend that business can continue to plan its strategies in the traditional mode. 相似文献
810.
Hübner Maria Martha Costa Austin John Miguel Caio F. 《The Analysis of verbal behavior》2008,24(1):55-62
In the current study, tacts with positive qualifying autoclitics for reading were reinforced in order to determine if this procedure would increase the time spent reading by participants. Participants included 5 children, between 9–10 years old. Participants were individually exposed to 4 free operant sessions during which they were instructed to independently choose play activities. During pre- and post-treatment conditions, no consequences were provided for choosing reading. In addition, 4 treatment sessions were conducted on days separate from the free operant session days, during which the experimenter praised each positive reading-related statement emitted by the participant. Following treatment sessions, 4 out of 5 participants increased the time allocated to reading, suggesting that reading could be increased when praise is delivered contingent upon positive reading-related verbalizations. 相似文献