Final answer:
The relative contribution of genetics and environment to personality is determined through studying twins and examining the concept of genetic environmental correlation. The theory of Range of Reaction also explains how genetic potential interacts with environmental stimulation.
Step-by-step explanation:
The relative contribution of genetics and environment to personality can be determined through various research methods. One approach is studying twins, both identical and fraternal, who were raised together or apart. Findings from the Minnesota Study of Twins Reared Apart suggest that identical twins, whether raised together or apart, have very similar personalities indicating a genetic influence. Another perspective is to examine the concept of genetic environmental correlation, which suggests that our genes influence our environment and vice versa. Additionally, the theory of Range of Reaction proposes that each person's genetic makeup determines their potential, but environmental stimulation can influence whether they reach that potential.