Statistical properties of the K-index for detecting answer copying

Leonardo Sotaridona, R.R. Meijer

Research output: Contribution to journalArticleAcademic

40 Citations (Scopus)
17 Downloads (Pure)


We investigated the statistical properties of the K-index (Holland, 1996) that can be used to detect copying behavior on a test. A simulation study was conducted to investigate the applicability of the K-index for small, medium, and large datasets. Furthermore, the Type I error rate and the detection rate of this index were compared with the copying index, o (Wollack, 1997). Several approximations were used to calculate the K-index. Results showed that all approximations were able to hold the Type I error rates below the nominal level. Results further showed that using o resulted in higher detection rates than the K-indices for small and medium sample sizes (100 and 500 simulees).
Original languageEnglish
Pages (from-to)115-132
Number of pages17
JournalJournal of educational measurement
Issue number2
Publication statusPublished - 2002


  • IR-58268
  • METIS-210624


Dive into the research topics of 'Statistical properties of the K-index for detecting answer copying'. Together they form a unique fingerprint.

Cite this