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761.
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
762.
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
763.
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
764.
Themes and Trends of Journal of Family and Economic Issues: A Review of Twenty Years (1988–2007) 总被引:1,自引:1,他引:0
This review article examines the progress and impact of the Journal of Family and Economic Issues (JFEI) between 1988–2007. Over the past 20 years, JFEI has become a major journal publishing articles on the relationship between families and economic systems. JFEI contributed to both the economic and family studies disciplines by publishing articles that explore the interface of these
two disciplines. Between 1988 and 2007, JFEI published articles on a variety of themes not often found in other economic or family studies journals such as family resource
management, consumer attitudes and behaviors, and economic issues and family relationships. Other unique characteristics of
JFEI include many collaborative multidisciplinary studies and many studies analyzing international or cross-cultural samples. 相似文献
765.
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
766.
Carol H. Meyer DSW 《Clinical Social Work Journal》1977,5(4):289-292
767.
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
768.
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
769.
Clinton G. Gudmunson Ivan F. Beutler Craig L. Israelsen J. Kelly McCoy E. Jeffrey Hill 《Journal of Family and Economic Issues》2007,28(3):357-376
Using a sample consisting of 4,997 married couples from the National Survey of Families and Households, individual emotional
distress, the occurrence of couple disagreements, couple fighting, and couple quality time together mediated the relationship
between financial strain and personal assessments of marital instability. The overall results suggest that financial strain
influences both positive and negative forms of couple interaction which are stronger mediators than personal emotional distress
of the relationship between financial strain and marital instability. The results further suggest that there were no gender
differences among these linkages. 相似文献
770.
This paper discusses the marketing concept and its impact on the strategy and structure of the business organization. The popular dictum that every firm should implement the marketing concept in its extreme form is challenged. Considerations of the overall structure of the firm, the time period in question, the amount of resources available are included in the determination of the degree of implementation which should be made. Finally, the conclusion indicates that the popular view that a change in environment necessitates a change in the organizational structure should be modified. The cost may be too great for the benefits derived. 相似文献