there is criticising evidence by Twenge et al (2004), who carried out a meta-analysis, comparing young people between 1960 and 2002. They found that in this time span, people have become more resistant to obedience, however also more external. This goes against locus of control as an explanation as you would expect the opposite; if resistance is linked to an internal locus of control, then as levels of resistance increased, we would expect people to have become more internal instead if the explanation was correct. This challenges the link between an internal locus of control and independent behaviour. However, Twenge et al suggest that this increase in external locus of control may be due to changing social factors. For example, increases in divorce, unemployment, violent crime, mental health problems, may have led young people to experience events over which they have no control.