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Visual-context and testlet IRT

Items displayed on the same screen, page, diagram, or stimulus can share presentation-context variance. fit_visual_context_irt() models that known design dependence as a separate testlet/context dimension rather than silently treating every item as independent.

registry <- visual_context_registry(
  item_metadata,
  item = "item_id",
  context = "screen_id"
)

fit <- fit_visual_context_irt(
  response_matrix,
  registry = registry,
  context = "screen_3"
)

compare_visual_context_irt(fit)
context_factor_effects(fit)
audit_visual_context_dependence(fit)
plot(fit, type = "loadings")
plot(fit, type = "difficulty_change")
plot(fit, type = "context_registry")

The context dimension represents shared presentation context unless independent substantive theory and validation justify another interpretation.

These binaries (installable software) and packages are in development.
They may not be fully stable and should be used with caution. We make no claims about them.