The HEX-ACO-18: Developing an age-invariant HEXACO short scale using Ant Colony Optimization

Abstract

In this study, we developed an age-invariant 18-item short form of the HEXACO Personality Inventory for use in developmental personality research. We employed a combination of the item selection procedure ant colony optimization (ACO) and the model estimation approach local structural equation modeling (LSEM). ACO is a metaheuristic algorithm that selects and evaluates items based on the quality of the resulting short scale, thus allowing for the direct optimization of criteria that can only be estimated based on combinations of items, such as model fit and measurement invariance across age. LSEM allows for model estimation and measurement invariance testing across a continuous age variable by weighting participants based on their age, rather than splitting the sample into artificial age groups. Using a HEXACO-100 dataset of N = 6,419 participants ranging from 16 to 90 years of age, we selected a short form optimized for model fit, measurement invariance, facet coverage, and balance of item keying. The resulting HEX ACO 18 short scale showed adequate model fit, scalar measurement invariance across age, and covered three out of four facets from each HEXACO trait domain. Furthermore, the usefulness and versatility of the item and person sampling procedures ACO and LSEM is demonstrated.

Short, Yet Creative: Compiling a Short Scale of Creative Activities

“…SHORT, YET CREATIVE 12 personality (e.g., Olaru et al, 2015;e.g., Olaru & Danner, 2021;Olaru & Jankowsky, 2021) or ability measures (e.g., Schroeders et al, 2016aSchroeders et al, , 2016b) by optimizing the fit of confirmatory measurement models, or by delivering desired group differences. ACO is especially valuable in short scale construction as it is possible to include several optimization criteria simultaneously.…”