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Estimation of epidemiological and population parameters from molecular sequence data has become central to the understanding of infectious disease dynamics. Various models have been proposed to infer details of the dynamics that describe epidemic progression. These include inference approaches derived from Kingman's coalescent theory. Here, we use recently described coalescent theory for epidemic dynamics to develop stochastic and deterministic coalescent SIR tree priors. We implement these in a Bayesian phylogenetic inference framework to permit joint estimation of SIR epidemic parameters and the sample genealogy. We assess the performance of the two coalescent models and also juxtapose results obtained with BDSIR, a recently published birth-death-sampling model for epidemic inference. Comparisons are made by analyzing sets of genealogies simulated under precisely known epidemiological parameters. Additionally, we analyze influenza A (H1N1) sequence data sampled in the Canterbury region of New Zealand and HIV-1 sequence data obtained from known UK infection clusters. We show that both coalescent SIR models are effective at estimating epidemiological parameters from data with large fundamental reproductive number $R_0$ and large population size $S_0$. Furthermore, we find that the stochastic variant generally outperforms its deterministic counterpart in terms of error, bias, and highest posterior density coverage, particularly for smaller $R_0$ and $S_0$. However, each of these inference models are shown to have undesirable properties in certain circumstances, especially for epidemic outbreaks with $R_0$ close to one or with small effective susceptible populations., Comment: Submitted

Parents' and teachers' ratings of social competence and problem behaviors for 164 special education students in grades K-3 were measured using the Social Skills Rating System. Weak to moderate relationships were found between parents' and teachers' ratings. Gender comparisons within the study group revealed mixed findings: teachers' ratings indicated that girls had better social skills but relatively similar levels of problem behaviors than boys, but parents' ratings indicated that boys were rated as having higher levels of both social skills and problem behaviors than girls. These results provide some additional evidence for the convergent validity of the SSRS and also suggest that source and setting variance strongly influence behavior ratings. These results also raise some interesting questions regarding gender differences in social behavior of young children with disabilities.

This study examined the relationship between ratings of adaptive behavior and social competence in a population of 208 students in kindergarten through third grade with a variety of disabilities using the Scales of Independent Behavior (SIB; Bruininks, Woodcock, Weatherman, & Hill, 1984) and the Social Skills Rating System (SSRS; Gresham & Elliott, 1990). Moderate yet statistically significant relationships between the SIB adaptive behavior scores and the SSRS social competence scores were found, with strongest correlations occurring between the SSRS and the Social and Communication subscale (r = .51) and Work Skills subscale (r = .60) on the SIB. Weak to near zero correlations were found between the SIB adaptive behavior scores and SSRS Problem Behaviors scores. This investigation provides new evidence for the concurrent criterion-related validity of both the SIB and the SSRS.

In this study 58 learning-disabled (LD), 48 mentally retarded (MR), 55 emotional-behavioral disordered (EBD), and 58 regular education (RE) students in grades one through six were compared on levels of social skills and problem social behaviors. Subjects were teacher-rated on the School Social Behavior Scales (SSBS; Merrell, 1993a). LD and MR groups had similar levels of adjustment, which were significantly poorer than the RE group, but significantly better than the EBD group. SSBS scores were found to predict overall group membership patterns to a significant extent and were most effective at predicting group membership of RE and EBD subjects, but less effective at predicting group membership of LD and MR subjects. Findings highlight the importance of positive and negative social functioning as discriminating variables and lend support to the discriminant validity of the SSBS and its use as a research, screening, and assessment tool.