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821.
Much research has been conducted to develop confidence Intervals on linear combinations and ratios of variance components in balanced and unbalanced random models.This paper first presents confidence intervals on functions of variance components in balanced designs.These results assume that classical analysis of variance sums of squares are independent and have exact scaled chi-squared distributions.In unbalanced designs, either one or both of these assumptions are violated, and modifications to the balanced model intervals are required.We report results of some recent work that examines various modifications for some particular unbalanced designs. 相似文献
822.
In response surface designs, it is not usually easy to handle the moment matrix X'X, especially for higher orders. This paper presents a method in which the moment matrix of a response surface of any order can be standardized, i.e., X'X splits into a diagonal matrix consisting of sub-matrices of lower order. This eases the calculation of the determinant and the inverse of X'X. The method has been illustrated with applications to second, third and fourth order response surfaces. 相似文献
823.
Children (aged 9, 14, 19, and 24 months) were encouraged to use tools to achieve a demonstrated goal. Each tool was most efficiently applied when held by the handle with the thumb toward the head of the tool in a radial grip. The tools were presented at midline and oriented to the left and right on alternating trials, so the children who managed to grasp a tool in both orientations with the radial grip demonstrated planning of actions in advance. The tools included a spoon, hairbrush, toy hammer, and magnet; the goals were to feed one's self, feed another, brush one's hair, brush another's hair, hit pegs, and retrieve metal objects. Children were found to use more radial grips with the self‐directed tools (i.e., hairbrush‐to‐self and spoon‐to‐self), indicating that they could plan their actions better when directed toward the self than toward an external goal. 相似文献
824.
825.
Application of the characterization theory to the mixture model 总被引:1,自引:0,他引:1
This paper indicates the potential application of the characterization theory to the mixture model. It discusses a particular example of a mixture model and concludes that successful application of this theory can be made in order to choose the appropriate mixture model and the mixing parameter. 相似文献
826.
827.
A review of image-warping methods 总被引:1,自引:0,他引:1
SUMMARY Image warping is a transformation which maps all positions in one image plane to positions in a second plane. It arises in many image analysis problems, whether in order to remove optical distortions introduced by a camera or a particular viewing perspective, to register an image with a map or template, or to align two or more images. The choice of warp is a compromise between a smooth distortion and one which achieves a good match. Smoothness can be ensured by assuming a parametric form for the warp or by constraining it using differential equations. Matching can be specified by points to be brought into alignment, by local measures of correlation between images, or by the coincidence of edges. Parametric and non-parametric approaches to warping, and matching criteria, are reviewed. 相似文献
828.
Rahul Mukerjee T.J. Rao & K. Vijayan 《Australian & New Zealand Journal of Statistics》2000,42(2):245-245
In the estimators t 3 , t 4 , t 5 of Mukerjee, Rao & Vijayan (1987), b y x and b y z are partial regression coefficients of y on x and z , respectively, based on the smaller sample. With the above interpretation of b y x and b y z in t 3 , t 4 , t 5 , all the calculations in Mukerjee at al. (1987) are correct. In this connection, we also wish to make it explicit that b x z in t 5 is an ordinary and not a partial regression coefficient. The 'corrected' MSEs of t 3 , t 4 , t 5 , as given in Ahmed (1998 Section 3) are computed assuming that our b y x and b y z are ordinary and not partial regression coefficients. Indeed, we had no intention of giving estimators using the corresponding ordinary regression coefficients which would lead to estimators inferior to those given by Kiregyera (1984). We accept responsibility for any notational confusion created by us and express regret to readers who have been confused by our notation. Finally, in consideration of the above, it may be noted that Tripathi & Ahmed's (1995) estimator t 0 , quoted also in Ahmed (1998), is no better than t 5 of Mukerjee at al. (1987). 相似文献
829.
SUMMARY Families of joint distributions for describing the lifetimes of a system of components that operate under an unknown environment, when the environment follows a Weibull distribution, are derived. The reliability function for this system is calculated and several properties of the aforementioned joint distributions are investigated. 相似文献
830.