Cognitive categorization processes in performance evaluation: Confirmatory tests of two models

We tested a data-driven ‘traditional’ model and a schema-driven ‘categorization’ model of rater cognitive processes. Raters viewed one of two videotaped lectures on economics. Next, they completed dimensional and overall performance ratings, and scales designed to measure performance-based and non-performance-based aspects of raters' general impressions. We tested model predictions using a combination of confirmatory factor analysis and single-equation regression estimates of structural parameters. Neither model received unequivocal support, though results favored the categorization model. We conclude that (a) performance-based and non-performance-based aspects of a rater's general impression can be distinguished empirically, (b) raters' overall impressions of ratees may substantially reflect the integration of performance-based information, and (c) performance evaluation may be better viewed in the context of ‘evaluation-based’ rather than ‘memory-based’ judgments.     

Modeling population effects of the Deepwater Horizon oil spill on a long-lived species

The 2010 Deepwater Horizon (DWH) oil spill exposed common bottlenose dolphins (Tursiops truncatus) in Barataria Bay, Louisiana to heavy oiling that caused increased mortality and chronic disease and impaired reproduction in surviving dolphins. We conducted photographic surveys and veterinary assessments in the decade following the spill. We assigned a prognostic score (good, fair, guarded, poor, or grave) for each dolphin to provide a single integrated indicator of overall health, and we examined temporal trends in prognostic scores. We used expert elicitation to quantify the implications of trends for the proportion of the dolphins that would recover within their lifetime. We integrated expert elicitation, along with other new information, in a population dynamics model to predict the effects of observed health trends on demography. We compared the resulting population trajectory with that predicted under baseline (no spill) conditions. Disease conditions persisted and have recently worsened in dolphins that were presumably exposed to DWH oil: 78% of those assessed in 2018 had a guarded, poor, or grave prognosis. Dolphins born after the spill were in better health. We estimated that the population declined by 45% (95% CI 14–74) relative to baseline and will take 35 years (95% CI 18–67) to recover to 95% of baseline numbers. The sum of annual differences between baseline and injured population sizes (i.e., the lost cetacean years) was 30,993 (95% CI 6607–94,148). The population is currently at a minimum point in its recovery trajectory and is vulnerable to emerging threats, including planned ecosystem restoration efforts that are likely to be detrimental to the dolphins’ survival. Our modeling framework demonstrates an approach for integrating different sources and types of data, highlights the utility of expert elicitation for indeterminable input parameters, and emphasizes the importance of considering and monitoring long-term health of long-lived species subject to environmental disasters. Article impact statement: Oil spills can have long-term consequences for the health of long-lived species; thus, effective restoration and monitoring are needed.