cNORMj - Continuous Norming for Jamovi

Overview

cNORMj provides conventional and regression-based continuous norming methods for psychometric test development in Jamovi. It is based on the cNORM package for R (Lenhard, Lenhard & Gary, 2018).

The continuous norming method produces norm scores by modeling the functional relationship between:

• Raw scores
• Norm scores
• Grouping variables (e.g., age, grade)

This approach:

• Reduces necessary sample size
• Closes gaps between norm groups
• Decreases error variance in norm data
• Smooths sampling errors

Modules

Single Group

For norming within a single group (e.g., all participants of the same age/grade).

Continuous Norming

For creating continuous norms across multiple groups or ages.

Key References

• Lenhard, A., Lenhard, W., Sebastian, S. & Segerer, R. (2018). A continuous solution to the norming problem. Assessment, 25, 112-125. doi:10.1177/1073191116656437
• Lenhard, A., Lenhard, W. & Gary, S. (2019). Continuous norming of psychometric tests: A simulation study of parametric and semi-parametric approaches. PLoS One, 14(9). doi:10.1371/journal.pone.0222279
• Lenhard, W. & Lenhard, A. (2020). Improvement of Norm Score Quality via Regression-Based Continuous Norming. Educational and Psychological Measurement, Online First, 1-33. doi:10.1177/0013164420928457

Further Information

More details and tutorials are available via Psychometrica.