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Abstract Spatial voting models are widely used in political science to analyze legislators’ preferences and voting behavior. Traditional models assume that legislators’ ideal points are static across different types of votes. This article extends the Bayesian spatial voting model to incorporate hierarchical Bayesian methods, allowing for the identification of covariates that explain differences in legislators’ ideal points across voting domains. We apply this model to procedural and final passage votes in the U.S. House of Representatives from the 93rd through 113th Congresses. Our findings indicate that legislators in the minority party and those representing moderate constituencies are more likely to exhibit different ideal points between procedural and final passage votes. This research advances the methodology of ideal point estimation by simultaneously scaling ideal points and explaining variation in these points, providing a more nuanced understanding of legislative voting behavior. 

Abstract Latent factor models are widely used in the social and behavioural sciences as scaling tools to map discrete multivariate outcomes into low-dimensional, continuous scales. In political science, dynamic versions of classical factor models have been widely used to study the evolution of justices’ preferences in multi-judge courts. In this paper, we discuss a new dynamic factor model that relies on a latent circular space that can accommodate voting behaviours in which justices commonly understood to be on opposite ends of the ideological spectrum vote together on a substantial number of otherwise closely divided opinions. We apply this model to data on nonunanimous decisions made by the US Supreme Court between 1937 and 2021, and show that for most of this period, voting patterns can be better described by a circular latent space. 

Successful reproduction is critical to the growth and persistence of marine fish populations, yet how changes in the environment influence reproduction remains largely unknown. We explored how shifting ocean conditions influenced larval production in four species of long-lived, live-bearing rockfish (Sebastes spp.) in the California Current. Brood fecundity, body size, and environmental information were analyzed from the mid-1980s through 2020. Interannual variation in brood fecundity was greater than 50% in the single-brooding yellowtail rockfish (S. flavidus) and widow rockfish (S. entomelas). Brood fecundity varied less in chilipepper (S. goodei) and bocaccio (S. paucispinis), two species capable of multiple broods per year. In these two species, interannual fecundity variability is more likely to depend on the number of broods produced than on brood size alone. In all four species, brood fecundity was positively correlated with maternal length and body condition. Variable ocean conditions influenced the strength of maternal size effects by year. These results provide evidence for reproductive plasticity and environmental effects on fecundity, with implications for changes in population reproductive potential with climate change.