NEWS

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coldstart 0.1.0.9000

• cs_check() now accounts for prediction error shared by all items of a family (the unseen family's unknown effect, or the estimation error of a seen family's effect). predict() returns this as sd_shared, estimated from the cross-validation and leave-one-family-out residuals, and cs_calibrate() carries it as prior_sd_shared. Previously a family unseen in training was falsely flagged 3.5-6% of the time at alpha = 0.01; it is now flagged at about the nominal rate. Seen families, detection of drifted families and calibration accuracy are unchanged. Calibrations without the new column behave exactly as before.

coldstart 0.1.0 (2026-10-07)

• Initial release.
• Difficulty prediction from item features with honest seen/unseen-family uncertainty (cs_predictor()).
• Grid-Bayes calibration with robust Student-t predicted priors (cs_calibrate()).
• Pretest sample-size planning (cs_plan()).
• Family-level trust diagnostics and prior withdrawal (cs_check(), cs_distrust()).