Distributions of simple patterns in some kinds of exchangeable sequences

In this article, we consider the distributions of simple patterns in some types of sequences of infinite exchangeable multi-state trials. The distributions on exchangeable multi-state trials are considered in terms of an extension of de Finetti's theorem. As an application of partially exchangeable sequences, distributions on a Markov exchangeable sequence are studied. Furthermore, we propose a new type of partially exchangeable sequence and examine its properties. In addition, we discuss the distribution theory in the case of the finite exchangeable sequences. The results presented here provide a wide framework for developing the exact distribution theory of simple patterns. Finally, some examples are given in order to illustrate our theoretical results.     

Settling-site selection and survival of two scale insects,Ceroplastes rubens andC. ceriferus, on citrus trees

Summary We studied settling-site selection and the resulting survival of two sessile scale insects,Ceroplastes rubens andC. ceriferus, in the citrus tree,Citrus unshiu, in central Japan. C. rubens preferred 0-year-old twigs most as a settling-site; the density of nymphs settling on 0-year-old twigs was significantly higher than those on ≥1-year-old twigs, and few nymphs settled on ≥3-year-old twigs. The mean survival rates from settling until reproduction in the next year were significantly higher on more preferred twigs than on less preferred ones. InC. ceriferus, nymphs significantly preferred 1- and 2-year-old twigs to 0- and ≥3-year-old ones, and the mean survival rates on the more preferred 1- and 2-year-old twigs were significantly higher than those on less preferred ≥3-year-old twigs. However, the survival rate on less preferred 0-year-old twigs was slightly higher than those on 1- and 2-year-old ones. Thus, in both species of scale, it was the preferred twigs which were more profitable sites for survival after settling, except for less preferred 0-year-old twigs forC. ceriferus. In both scale species, most mortality was due to growth cessation, which is believed to be related to the twig quality as a food source. Predators and parasitoids were minor mortality factors. Both species showed constant survival rates until the density of settled nymphs exceeded double the “upper-limit” density, whereupon they decreased drastically. Nymphs ofC. rubens settling on twigs of high scale density showed a spacing-out distribution, those ofC. ceriferus did not. InC. rubens, an increase in preference for originally less profitable twigs at the later stage of the settling season was observed, but not inC. ceriferus. Accordingly, individuals ofC. rubens showed a stronger tendency to avoid conspecifics than didC. ceriferus. Although nymphs of the two scales clearly preferred more profitable sites, their settling-site selection did not agree with the predictions from the ideal free distribution theory (Fretwell and Lucas, 1970). The discrepancies were (1) frequent settling on less profitable sites at the early stage of the settling season, (2) insufficient utilization of the most profitable twigs, and (3) virtually 100% mortality on overcrowded twigs under conditions where unoccupied profitable twigs still remained. These discrepancies are thought due to the limited dispersal time of nymphs. Contribution to the ecological studies of scale insects 2.     

Methods for Studying Generalized Birthday and Coupon Collection Problems

In this paper, we consider generalizations of two classical probability problems: the birthday problem and the coupon collector's problem. These problems are discussed in terms of urn models and captured through generating functions. Some methods for the study of the problems are presented. Furthermore, we also formulate the generalized birthday and coupon collector's problems as the waiting time problems. In each case, numerical examples are given in order to illustrate the feasibility of our methods.     

Predicting a Partner's End‐of‐Life Preferences,or Substituting One's Own?

Numerous studies comparing patients' end‐of‐life health care treatment preferences with their surrogates' reports of those preferences indicate that partners do not know one another's treatment preferences: Random guesses are just as likely as surrogate choices to match the patients' preferences. The present study uses the empathic accuracy model and the assumed similarity model to shed further light on accuracy and bias in surrogate reports. The data come from the National Center for Family and Marriage Research/Knowledge Networks Pilot Study 2010, a national sample of 1,075 heterosexual American couples age 18 to 64. Surrogate reports were simultaneously biased (i.e., correlated with the surrogate's own preference) and accurate (i.e., correlated with the partner's actual preference). Higher relationship quality and legal marriage (vs. cohabitation) were associated with increased assumed similarity bias. These findings suggest that practitioners working in end‐of‐life care need to be familiar with their partnered patients' relationship dynamics.     

Teaching Note—Creating an Integrative Research Learning Environment for BSW and MSW Students

ABSTRACT

Research courses are often the least popular among BSW and MSW students because the connection between social work practice and research is not always evident. This teaching note introduces the structure of the Social Work integrative Research Lab (SWiRL), which was implemented in a social work program without a doctoral program at a large public university. SWiRL offers students opportunities to engage meaningfully in a variety of social work research projects using a framework of nested mentoring. Students gain hands-on research experience while they develop confidence, leadership, and mentoring skills within this structure. The authors discuss recommendations for other social work programs that do not have doctoral education or an established research environment.     

The Adaption of Management Accounting Systems to Changing Market Conditions: Japanese Evidence

This paper considers how Japanese management accounting interfaces with the new production environments being implemented in Japan. A review of evidence on the relative importance of the set of management accounting and production engineering techniques is presented. On the basis of these results the paper presents tentative predictions about the evolutionary path of future management accounting in Japan.