Abstract: Personality assessment was reborn in industrial and organizational psychology, which promoted researchers to concern on quality and fairness in personality tests. Some researchers put forward the ideal point process hypothesis of item response in personality tests, by which they developed generalized grade unfolding model (GGUM) to analyze participants’ response data on personality tests, and to construct some personality scales, and found that GGUM fit the data better than dominant models. However, some current researches on item response process were not based on experimental evidence from laboratory, but on investigations from large samples. In addition, current popular GGUM can not fit the categorical data in personality tests. In the future, GGUM must be extended and some models which fit the data on forced-choice personality test must be developed.

Key words: personality test, ideal point process, unfolding model