Chapter 5 Modelling equates

This section deals with the nitty-gritty of the modelling strategy used for the GCDG data introduced in Section 2. This section

• provides a high-level description of the GCDG data (5.1)
• discusses various modelling strategies (5.2)
• shows the impact of equate groups on the model in extreme cases (5.3)
• demonstrates visualisation of age profiles to select promising equate groups (5.4)
• introduces a helpful visualisation of the quality of the equate group (5.5)
• highlights infit and outfit for removing misfitting milestones (5.6)
• discusses instrument fit and equate group editing (5.7)
• introduces a grading system for equate groups (5.8)
• provides pointers to the final model (5.9)