Get Topic Prevalence (Gamma) from STM Model — get_topic

Extracts topic prevalence values (gamma/theta) from a fitted STM model, returning mean prevalence for each topic as a data frame.

Usage

get_topic_prevalence(stm_model, category = NULL, include_theta = FALSE)

Arguments

stm_model: A fitted STM model object from stm::stm().
category: Optional character string to add as a category column.
include_theta: Logical, if TRUE includes document-topic matrix (default: FALSE).

Value

A data frame with columns:

topic: Topic number
gamma: Mean topic prevalence across documents
category: Category label (if provided)

Examples

if (interactive() && requireNamespace("stm", quietly = TRUE)) {
  # Requires fitting an STM model first; uses 'stm::gadarian' for demo
  data("gadarian", package = "stm")
  proc <- stm::textProcessor(gadarian$open.ended.response, metadata = gadarian)
  prep <- stm::prepDocuments(proc$documents, proc$vocab, proc$meta)
  topic_model <- stm::stm(prep$documents, prep$vocab, K = 3,
                           data = prep$meta, max.em.its = 5,
                           verbose = FALSE)
  prevalence <- get_topic_prevalence(topic_model)
  prevalence_label <- get_topic_prevalence(topic_model, category = "demo")
}