| calibrate | Calibrate IRT models per group |
| dependent_vcov | Item parameter covariance for dependent person samples |
| detect_dif | Detect differential item functioning |
| estimate_trend | Estimate a longitudinal IRT trend |
| irtlink-plots | Plot methods for irtlink objects |
| linking_design | Inspect the linking design of a data set list |
| linking_error | Linking error of a linked trend |
| link_groups | Linking across groups |
| person_scores | Person parameter estimates for an em calibration |
| plot.irtlink_dif | Plot methods for irtlink objects |
| plot.irtlink_link | Plot methods for irtlink objects |
| plot.irtlink_trend | Plot methods for irtlink objects |
| sim_trend_data | Simulate longitudinal item response data |