What You Don't Know Can Hurt You: Missing Data and Partial Credit Model Estimates.

The authors investigated the effect of missing completely at random (MCAR) item responses on partial credit model (PCM) parameter estimates in a longitudinal study of Positive Affect. Participants were 307 adults from the older cohort of the Notre Dame Study of Health and Well-Being (Bergeman and Deboeck, 2014) who completed questionnaires including Positive Affect items for 56 days. Additional missing responses were introduced to the data, randomly replacing 20%, 50%, and 70% of the responses on each item and each day with missing values, in addition to the existing missing data.

Test Reliability at the Individual Level.

Reliability has a long history as one of the key psychometric properties of a test. However, a given test might not measure people equally reliably. Test scores from some individuals may have considerably greater error than others.

Measuring positive and negative affect in older adults over 56 days: comparing trait level scoring methods using the partial credit model.

Positive (PA) and negative affect (NA) are important constructs in health and well-being research. Good longitudinal measurement is crucial to conducting meaningful research on relationships between affect, health, and well-being across the lifespan. One common affect measure, the PANAS, has been evaluated thoroughly with factor analysis, but not with Racsh-based latent trait models (RLTMs) such as the Partial Credit Model (PCM), and not longitudinally.

A comparison of diversity, frequency, and severity self-reported offending scores among female offending youth.

[Correction Notice: An Erratum for this article was reported in Vol 24(3) of Psychological Assessment (see record 2012-04601-001). The article contained a number of errors which are corrected in the erratum.] Despite general consensus over the value of measuring self-reported offending, discrepancies exist in methods of scoring self-reported offending and the length of the reference period over which offending is assessed.