Final answer:
Hansen's Theory is a research study conducted by Marcus Lee Hansen that explores the relationship between parenthood and happiness. It compares traditional beliefs with scientific evidence gathered from social indicators research.
Step-by-step explanation:
Hansen's Theory refers to the parental happiness theory proposed by Marcus Lee Hansen. The theory explores the relationship between parenthood and happiness, comparing anecdotal beliefs with empirical evidence. Hansen's research examines the folk theories surrounding parenthood and happiness and contrasts them with scientific findings gathered from social indicators research. The study suggests that there may be a disconnect between popular beliefs and the actual impact of parenthood on happiness.