Unscripted E8: Modeling Unobserved (Latent) Population Heterogeneity

Описание: In Episode 7 of Unscripted Patrick and Dan considered what to do when the estimated parameters of a model might differ across known subpopulations (e.g., biological sex, race). In this episode they tackle an even harder problem: what if the subpopulations are hypothesized but neither known nor observed? For example, in studying individuals diagnosed with attention deficit hyperactivity disorder, we might hypothesize that there are subtypes distinguished by different profiles of inattention, impulsivity, motor restlessness, and distraction, that these subtypes may differ on academic and social functioning, and that treatment interventions could potentially vary across subtypes. The challenge is that we don't know in advance how many subtypes there are, their corresponding symptom profiles, or which subjects belong to which subtype. In this episode Patrick and Dan discuss modeling approaches that allow researchers to discern unobserved (or latent) population heterogeneity and determine the number, nature, and implications of underlying groups.

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