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951.
Haoli Wang Xirong Xu Yuansheng Yang Kai Lü 《Journal of Combinatorial Optimization》2011,21(4):481-496
Let G=(V,E) be a graph without an isolated vertex. A set D⊆V(G) is a k
-distance paired dominating set of G if D is a k-distance dominating set of G and the induced subgraph 〈D〉 has a perfect matching. The minimum cardinality of a k-distance paired dominating set for graph G is the k
-distance paired domination number, denoted by γ
p
k
(G). In this paper, we determine the exact k-distance paired domination number of generalized Petersen graphs P(n,1) and P(n,2) for all k≥1. 相似文献
952.
953.
This paper numerically examines the size robustness of various conditional moment tests in misspecified tobit and probit models. The misspecifications considered include the incorrect exclusion of regressors, ignored heteroskedasticity and false distributional assumptions. An important feature of the experimental design is that it is based on an existing empirical study and is more realistic than many simulation studies. The tests are seen to have mixed performance depending on both the original null hypothesis being tested and type of misspecification encountered. 相似文献
954.
955.
OLE F. CHRISTENSEN MORTEN FRYDENBERG JENS L. JENSEN JØRGEN G. PEDERSEN 《Scandinavian Journal of Statistics》2007,34(2):347-364
Abstract. The large deviation modified likelihood ratio statistic is studied for testing a variance component equal to a specified value. Formulas are presented in the general balanced case, whereas in the unbalanced case only the one-way random effects model is studied. Simulation studies are presented, showing that the normal approximation to the large deviation modified likelihood ratio statistic gives confidence intervals for variance components with coverage probabilities very close to the nominal confidence coefficient. 相似文献
956.
957.
958.
Advocates of open adoption believe that it lightens and in some cases alleviates the grieving process after relinquishment. Advocates of confidential adoption, however, believe that open adoption limits and denies the grieving process that must take place for subsequent life adjustment. A study of 59 women who had placed a child for adoption through an agency--18 via open adoption and 41 via confidential adoption--revealed significant differences between the two groups on five subscales of the research instruments. Implications of this pioneer study in this new practice area are discussed and further research suggested. 相似文献
959.
960.
Each day for five days, 79 fifth‐grade children reported on events that occurred at school and they and their parents described their interactions with each other each evening. Consistent with previous research, it was found that on days when children reported more academic or peer problems during the day at school, they later described more aversive interactions with their parents. As hypothesized, increases in anxiety and drops in children's state self‐esteem partially mediated this link. However, parents did not report any differences in their interactions with the target child on days when the child experienced problems at school. This study suggests that negative events experienced by children while at school lead to short‐term changes in mood and self‐esteem, which influence their perceptions of subsequent interactions at home with parents. 相似文献