Other causes of measured variation in a trait are characterized as environmental factors, including observational error. The concept of heritability can be expressed in the form of the following question: 'What is the proportion of the variation in a given trait within a population that is not explained by the environment or random chance?' Heritability is a statistic used in the fields of breeding and genetics that estimates the degree of variation in a phenotypic trait in a population that is due to genetic variation between individuals in that population.
This is not the same as asking to what extent do genetic factors influence height in any one person. Studies of heritability ask questions such as to what extent do genetic factors influence differences in height between people.
