Testing stability of self-control over time among South Korean Youth using semi-parametric group-based modeling*

Gottfredson and Hirschi argued the self-control theory in A General Theory of Crime (1990). Since then, many studies have examined the central proposition of low self-control as the cause of criminal behavior with crosssectional data. However, few research studies have tested other stability propositions that low self-control is stable across the life-course and that once it is established at age 8 to 10, it remains relatively stable regardless of life changes. The purpose of this study was to examine stability postulate of the self-control theory. The current study used six-wave panel data of the Korean Children & Youth Panel Survey (KCYPS), which measured selfcontrol of elementary school students at one year each of time points. The test of relative stability hypothesis comprises four analyses of data: correlations, individual change scores, SGM (Semi-parametric Group-based Modeling), and Multinomial Logistic Regression. Results revealed that the hypothesis of self-control stability was not strongly supported by the longitudinal data. Based on prior empirical research and this study's finding, more research is needed to determine the stability of self-control.