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Table 3 DIF statistics (1PL model)

From: An item response theory approach to longitudinal analysis with application to summer setback in preschool language/literacy

  Item AIC BIC Change
All Constrained 69456.0 69696.9 --
Free 1 68898.0 69197.8 −558.1
  2 69120.3 69420.1 −335.7
  3 69057.2 69357.0 −398.8
  4 69286.3 69586.1 −169.7
  5 69438.2 69738.0 −17.9
  6 69430.4 69730.2 −25.7
  7 69301.7 69601.5 −154.3
  8 69273.8 69573.6 −182.3
  9 69415.3 69715.1 −40.8
  1-3 68179.6 68597.3 −1276.5
  1. Note. Change statistics are based on the simulated distribution of −2 log likelihood of the fitted model. The change values in the last column can be roughly interpreted as chi-square statistics with 12 degrees of freedom.