This paper develops a procedure for measuring how much is gained, and at what precision, by students in a pre-test and post-test situation against a target score on the post-test. We define our productivity index, M j , for teacher j as the ratio of estimated gains to an estimated standard that is the distance between an estimate of the pre-test score and the target score. Using language, mathematics, and reading scores on the SAT 9 for 1999 and 2000 from 75 public elementary classrooms (grades 3, 4, 5, and 6 in 2000), we employ a Bayesian implementation of a multivariate mixed model for repeated test scores from individual students who in turn are nested within teachers. Our analysis point to statistically significant gains on the whole for grades 3, 4, and 6. The strength of the approach lies in a straightforward estimation of the productivity index. Using the simulated sampling distribution of the posterior mean of the productivity index, we introduce a fuller depiction of progress in the productivity curve, or productivity profile, by calculating the probability that the index exceeds set proportions of the estimated standard. The basic model employed in this study thus contributes three essential components for sound accountability decisions. First, it estimates correlated measurement errors when using multiple measures. In doing so, we take full advantage of the informational redundancy in the measures. Second, it estimates initial status and value-added gains simultaneously. Lastly, it proposes a productivity index along with new procedures for representing the uncertainty in individual productivity estimates in the form of a productivity profile. This approach also facilitates a Bayesian e#ect-size analysis free from frequentist appeals to non-central t- or F- d...

Using rich longitudinal data from the Early Childhood Longitudinal Study – Kindergarten cohort (ECLS-K), we find that children who attended preschool enter public schools with higher levels of academic skills than their peers who experienced other types of child care (effect size of.14). This study considers the circumstances under which the preschool advantage persists, that is, the types of classrooms in which students who did not attend preschool “catch up ” to their counterparts who did. Specifically, we focus on two dimensions of the early school environment – class size and the level of academic instruction provided. The findings suggest that most of the preschool-related gap in academic skills at school entry is quickly eliminated for children placed in small classrooms providing high levels of reading instruction. Conversely, the initial disparities persist for children experiencing large classes and lower levels of reading instruction. These results point out that the longer-term effects of early childhood experience partly depend on classroom experiences during at least the first years of school.

In this paper we will argue that quasi-experiments can be equated to theoretical randomized experiments based on the extent of statistical control for confounding factors accounted for by measures such as a pre-test. That is, we use theoretical randomization as a baseline for evaluating the effective control of any study instead of using a single randomized empirical study as a gold standard against which to compare others. Ultimately, we will report that the quasi-experiment in Hong and Raudenbush (2005) used to infer an effect of kindergarten retention on reading achievement crosses the threshold for equivalence with a theoretical randomized study. We then develop a general formula and guidelines for equating quasi-experiments and randomized experiments based on the degree of statistical control achieved. In the discussion we emphasize the validity of causal inferences from quasi-experiments. 2

Research article Lack of cortisol response in patients with posttraumatic stress disorder (PTSD) undergoing a diagnostic interview

Acknowledgements: This study would not have been possible without the help and assistance of numerous individuals and institutions, including Indiana University and the School of Public and Environmental Affairs and Indianapolis Power and Light. This material is based upon

Despite much research, debate continues about the impact of risk taking on a firm’s future performance. Unlike prior studies, we propose that risk-return relationships evolve as firms age and learn, particularly in high-velocity settings where accumulated knowledge affects how firms respond to technological change. Discerning this requires three things absent from prior analyses: (1) studying an entire population; (2) modeling evolutionary processes; and (3) using separate models to capture how a firm’s gains and losses (i.e., its strong and weak performances) unfold across time. Using this framework, we found that (a) risk-return relationships generally evolved from positive to negative as firms aged; because (b) firms learned to avoid large losses at younger ages than they learned to sustain large gains; yet (c) the risk taking that followed below-aspiration performance moderated those effects such that major setbacks prompted large future gains and large future losses among older firms and downward spirals among younger ones. 1 Relationships between risk and return are central to our lives. In the hope of emotional or monetary rewards, some people take risks by climbing mountains, changing employers, or switching careers. Some executives take risks in pursuit of better pay and enhanced reputations, and some firms pursue risky strategies in a quest for higher sales and profits.

When (and for What) Does AFDC Receipt Matter? Over the last decade or so, with many Ohio State colleagues, we have been seeking to understand how parental characteristics, resources, and experiences affect their children’s lives. Our approach, drawing on resource, socialization, and social stress frameworks, has focused attention on linkages between both work and family circumstances and child outcomes – both cognitive and social. We have also considered how aspects of the family environment and mother-child interaction may mediate or moderate such linkages (see for example, Menaghan and Parcel, 1991, 1995, Menaghan, 1997, and Jekielek, 1998 on levels and changes in home environments; Parcel and

TMT COORDINATION NEEDS AND THE CEO PAY GAP:

This article bridges the gap in studies of the social bases of democratization between qualitative studies focused on social groups and quantitative studies focused on national characteristics. Qualitative historical evidence suggests the importance of classes—in particular, the emerging class of intellectuals—in the wave of democratizations in the decade before World War I. Quantitative cross-national data on a more recent wave of democratizations, from 1989 to 1996, confirm these findings. Models using direct maximum-likelihood estimation find that the ratio of adults with higher education has a significant positive effect on change in democracy levels, as measured by two longitudinal scales (Polity IV and Polyarchy). Proxies for the working class and the middle class—candidates proposed in previous studies as the social basis of democratization—also have significant effects. The study of the social bases of democratization has long been split in two: a qualitative case-oriented tradition that takes account of historical process and a quantitative tradition that maximizes sample size to address case-selection biases (Rueschemeyer, Stephens, and Stephens 1992, pp. 12–39). We propose that these two traditions differ also in their substantive 1

at the University of Wisconsin-Madison for useful comments and suggestions on earlier drafts.