The Beta-Poisson Distribution in Wadley’s Problem

In dose-response studies, Wadley’s problem occurs when the number of organisms that survive exposure to varying doses of a treatment is observed but the number initially present is unknown. The unknown number of organisms initially treated has traditionally been modelled by a Poisson distribution, resulting in a Poisson distribution for the number of survivors with parameter proportional to the probability of survival. Data in this setting are often overdispersed. This study revisits the beta-Poisson distribution and considers its effectiveness in modelling overdispersed data from a Wadley’s problem setting.     

Introducing the Historical Thinking Practice of Contextualizing to Middle School Students

This article describes the design of a social studies unit about the Johnstown Flood of 1889 with a particular emphasis on how specific unit resources engaged middle school students in learning about the geographical and historical context of Johnstown, Pennsylvania. We also report on how the resources supported the teaching and learning of the historical thinking practice of contextualizing.     

Robustness and Precision: How Data Quality May Influence Key Dependent Variables in Infant Eye‐Tracker Analyses

In recent years, eye‐tracking has become a popular method for drawing conclusions about infant cognition. Relatively little attention has been paid, however, to methodological issues associated with infant eye‐tracking. Here, we consider the possibility that systematic differences in the quality of raw eye‐tracking data obtained from different populations and individuals might create the impression of differences in gaze behavior, without this actually being the case. First, we show that lower quality eye‐tracking data are obtained from populations who are younger and populations who are more fidgety and that data quality declines during the testing session. Second, we assess how these differences in data quality might influence key dependent variables in eye‐tracking analyses. We show that lower precision data can appear to suggest a reduced likelihood to look at the eyes in a face relative to the mouth. We also show that less robust tracking may manifest as slower reaction time latencies (e.g., time to first fixation). Finally, we show that less robust data can manifest as shorter first look/visit duration. We argue that data quality should be reported in all analyses of infant eye‐tracking data and/or that steps should be taken to control for data quality before performing final analyses.     

Is it Just Me? Exploring Perceptions of Organizational Culture Change

A review of the literature on organizational culture change suggests that the field might benefit from studies combining both etic (researcher) and emic (employee) perspectives to examine individuals’ views regarding how and why their culture has changed. This paper seeks to deepen researchers’ knowledge of how individuals perceive organizational culture change by undertaking a two‐part study within an organization that has undergone planned cultural change initiatives. More specifically survey (i.e. etic view) data and interview (i.e. emic view) data are used to explore: (1) factors associated with (a) whether an individual will perceive that culture change has occurred, and (b) whether they categorize this change as for the better, for the worse or one that could not be categorized using these two labels; and (2) individuals’ rationales for why the culture has changed. The findings are mixed regarding the extent to which they support or refute existing research on organizational culture change.     

Debating Temporary Uses for Vacant Urban Sites: Insights for Practice from a Stakeholder Workshop

Temporary land uses have become the focus of much debate within academic and policy circles in recent years. Although the international literature contains numerous case studies of temporary interventions, little attention has been paid to the dynamics of the interactions among different stakeholders. This paper reports on a stakeholder workshop that used a participatory research approach to collectively define the issues facing those interested in the potential of vacant urban sites. The paper outlines the goals, design and evaluation of the workshop and concludes with a discussion of suggested lessons for practice that emerged from the workshop sessions.     

The construction of optimal designs for dose-escalation studies

Methods for the construction of A-, MV-, D- and E-optimal designs for dose-escalation studies are presented. Algebraic results proved elusive and explicit expressions for the requisite optimal designs are only given for a restricted class of traditional designs. Recourse to numerical procedures and heuristics is therefore made. Complete enumeration of all possible designs is discussed but is, as expected, highly computer intensive. Two exchange algorithms, one based on block exchanges and termed the Block Exchange Algorithm and the other a candidate-set-free algorithm based on individual exchanges and termed the Best Move Algorithm, are therefore introduced. Of these the latter is the most computationally effective. The methodology is illustrated by means of a range of carefully selected examples.     

Modeling Insurer‐Homeowner Interactions in Managing Natural Disaster Risk

The current system for managing natural disaster risk in the United States is problematic for both homeowners and insurers. Homeowners are often uninsured or underinsured against natural disaster losses, and typically do not invest in retrofits that can reduce losses. Insurers often do not want to insure against these losses, which are some of their biggest exposures and can cause an undesirably high chance of insolvency. There is a need to design an improved system that acknowledges the different perspectives of the stakeholders. In this article, we introduce a new modeling framework to help understand and manage the insurer's role in catastrophe risk management. The framework includes a new game‐theoretic optimization model of insurer decisions that interacts with a utility‐based homeowner decision model and is integrated with a regional catastrophe loss estimation model. Reinsurer and government roles are represented as bounds on the insurer‐insured interactions. We demonstrate the model for a full‐scale case study for hurricane risk to residential buildings in eastern North Carolina; present the results from the perspectives of all stakeholders—primary insurers, homeowners (insured and uninsured), and reinsurers; and examine the effect of key parameters on the results.