Computes quantitative dispersion metrics for terms, measuring how evenly distributed they are across the corpus.
Value
Data frame with columns:
term: The search term
frequency: Total occurrences
doc_count: Number of documents containing term
doc_ratio: Proportion of documents containing term
juilland_d: Juilland's D dispersion (0-1, higher = more even), computed on within-document proportions
rosengren_s: Rosengren's S dispersion adjusted for document sizes (1/n_docs to 1, higher = more even)
