1. DIFtree::data_sim_PCM
    Simulated Data Set with Polytomous Items
    data.frame|500 x 4
  2. DIFtree::data_sim_Rasch
    Simulated Data Set with Dichotomous Items
    data.frame|500 x 5
  3. ordDisp::reti
    Example Retinopathy
  4. structree::CTB
    Achievement Test from CTB/McGraw-Hill
  5. structree::guPrenat
    Prenatal Care in Guatemala
  6. structree::rent
    Munich Rent Data