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Glite Dictionary
infit

infit

9.9
A number that shows how well test results match a model
  • noun
  • Specialized
: infit
  • The infit statistic indicates how well the responses match the expected model in psychometric testing.

Examples

  • Removing the four worst-fitting cases and another four individual observations on item 21 reduced the standardized outfit SD from 2.1 to 1.8, and the standardized infit SD from 2.3 to 2.2.

    Academic text (2009)

  • High values of infit suggest that some participants may not be responding consistently to the test items.

  • Several students, however, appear to have provided inconsistent responses, as the maximum information-weighted (infit) and outlier-sensitive (outfit) statistics are 5.7 and 5.2, respectively.

    Academic text (2009)

  • Researchers used the infit measure to determine the validity of their model in analyzing student performance.

Surface Forms

infit singular
infits plural

Etymology

The word infit is formed from the part in- meaning 'in' and the familiar word fit meaning 'suitable' or 'matching'. A helpful way to remember it is to think of an item being 'in fit' with a model, so infit measures how well the data 'match' the model's expectations.