FIGURE 11.5 Income Inequality and Murder A study of 33 countries found a very strong link between the level of income inequality in a country and the homicide rate (Elgar & Aitken, 2010). As you can see in this graph, many countries, such as Japan, are low in both inequality and homicide, whereas others, such as South Africa, are very high in both. The United States is above average for both measures. The correlation between these two measures demonstrates that sociocultural factors, in addition to biological and psychological factors, are important predictors of aggression.
Source: Data from Elgar & Aitken (2010).