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211.
Tables have been prepared for the construction and selection of multiple dependent (deferred) state (MDS) sampling plans of type MDS-(c1,c2). These plans are compared with conventional sampling plans (such as single and double sampling) and it is shown that MDS-type plans require a smaller sample size. A special feature of the MDS-(0,1) plan is highlighted and its design procedure is indicated. 相似文献
212.
K. V. Mardia 《Journal of applied statistics》1998,25(2):231-235
SUMMARY Fisher has presented various applications of the repeated integral of the normal distribution function. A new application has appeared in shape distributions. This work has led to the search for an explicit expression for the repeated normal integral function in place of an infinite series expansion for this function first given by Fisher. We provide an explicit expression for this function with a finite number of terms. 相似文献
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Nhu D. Le Weimin Sun & James V. Zidek 《Journal of the Royal Statistical Society. Series B, Statistical methodology》1997,59(2):501-510
In a network of s g sites, responses like levels of airborne pollutant concentrations may be monitored over time. The sites need not all measure the same set of response items and unmeasured items are considered as data missing by design . We propose a hierarchical Bayesian approach to interpolate the levels of, say, k responses at s u other locations called ungauged sites and also the unmeasured levels of the k responses at the gauged sites. Our method involves two steps. First, when all hyperparameters are assumed to be known, a predictive distribution is derived. In turn, an interpolator, its variance and a simultaneous interpolation region are obtained. In step two, we propose the use of an empirical Bayesian approach to estimate the hyperparameters through an EM algorithm. We base our theory on a linear Gaussian model and the relationship between a multivariate normal and matrix T -distribution. Our theory allows us to pool data from several existing networks that measure different subsets of response items for interpolation. 相似文献
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A method of constructing resolvable incomplete block designs for v(=ks, 2 ≤ k ≤ s - 1) treatments in blocks of size k using mutually orthogonal Latin squares is proposed. It has been seen in particular that when the number of replications is s — 1 (or s), which is feasible if s is a prime or a prime power, the method gives PBIB (3) (or semi-regular GD) designs. The analysis of such designs has also been discussed. 相似文献
218.
Growing recognition of male sexual abuse and its potentially debilitating effects has underscored the need to develop effective treatment interventions for this population. The present study describes an individual treatment programme that was developed for adult males who have experienced childhood sexual abuse. The treatment programme focused on three areas related to sexual abuse, specifically feelings of self‐blame, anger and anxiety. The study also presents preliminary findings on treatment effects, using self‐report measures that five participants completed prior to treatment and at various assessments following treatment termination. Overall findings indicated improvements in behavioural self‐blame, anger, state anxiety and trait anxiety. Treatment did not appear to have an effect on characterological self‐blame over the long term. The study's findings are limited by the reliance on self‐report data and the absence of a comparison group. As such, our findings should be viewed as an initial contribution to the currently limited empirical data on treatment effects for sexually abused adult males. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
219.
Akshay Mutha Saurabh Bansal V. Daniel R. Guide 《Production and Operations Management》2016,25(8):1449-1464
We discuss the optimal raw material acquisition strategy for a third party remanufacturer (3PR). We specifically investigate whether a 3PR should acquire used products or cores in bulk with uncertain quality levels, or in sorted grades with known quality levels; and whether to acquire and remanufacture cores before the demand is realized (planned acquisition), or after the demand is realized (reactive acquisition), or on both occasions (sequential acquisition). When only sorted cores are acquired, we find that, (i) it is optimal to acquire cores in multiple grades to balance acquisition and remanufacturing costs; (ii) if reactive acquisition is possible, it reduces the assortment size (number of grades in which cores are acquired) and the total inventory acquired in the planned acquisition; and (iii) the optimal portfolio of grades to acquire and the optimal acquisition and remanufacturing quantities of these grades can be determined analytically. When bulk cores are acquired in addition to sorted cores, the property of reduction in assortment size of the planned acquisition is preserved. We also show that the 3PR should acquire only a fraction of the demand in planned acquisition, and leave the rest for reactive acquisition. This fraction changes during the lifecycle of a remanufactured product. Using a combination of empirical and realistic data from a smartphone remanufacturer we show that sequential acquisition increases expected profit by up to 8% and 27% over only planned and only reactive acquisitions respectively, and reduces the inventory acquired by up to 21% over only planned acquisition. 相似文献
220.
Infants of Depressed Mothers Show Reduced Gaze Activity During Mother–Infant Interaction at 4 Months 下载免费PDF全文
Mette S. Væver Marianne T. Krogh Johanne Smith‐Nielsen Torben T. Christensen Anne Tharner 《Infancy》2015,20(4):445-454
Gaze is one of the main means of communication in young infants, and it has been shown to be important for subsequent socio‐emotional and cognitive development. Maternal depression is a well‐known risk factor for disrupting mother–infant interactions, but findings regarding gaze behavior in infants of depressed versus nondepressed mothers have been ambiguous. In this study, we examined gaze duration and activity in a sample of 27 infants of mothers with postpartum depression (PPD) and 49 infants of nondepressed mothers. Maternal depressive symptoms were assessed with the Edinburgh Postnatal Depression Scale, and diagnoses were confirmed in clinical interview. Infant gaze was assessed during 4‐month face‐to‐face interactions using continuous timed‐event coding with high temporal resolution. Although we found no differences in gaze duration, infants of PPD mothers had both significantly less Gaze On and also less Gaze Off events. Findings suggest that PPD is related to reduced gaze activity during mother–infant interaction in 4‐month‐olds. This reduced activity may have long‐term negative consequences for child development. 相似文献