PSYC 2400 Lecture Notes - Lecture 5: Twin Study, Auton, Active Child
Document Summary
Shared environments- growing up together in the same family. Little effect of shared environment on some aspects of development. Nonshared environments- effects include experiences unique to the individual. With different levels of genetic similarity and essential equal environmental similarity, the difference between the correlations for the two types of twins is treated as an index of the importance of genetic factors in development. If you want to know about the effect of environment, you have to keep the amount of shared genes the same. A statistical estimate of the proportion of variance on a given trait among individuals in a given population that is attributable to genetic differences among those individuals (vs. environmental factors) Apply only to a particular group living at the same time. Can differ markedly for groups of people who grow up in very different environments. Does not mean that 60% of contracting depression is due to genes and 40% to the environment.
