Historically, psychologists have viewed femininity and masculinity as opposite poles of a continuum. The more feminine a person was, the less masculine that person could be. In the late 1990s, psychologists, including Sandra Bem, have asserted that femininity and masculinity are independent personality dimensions. Individuals, female or male, who exhibit high levels of both feminine and masculine personality traits are said to demonstrate androgyny. People who have many masculine but few feminine traits are termed masculine; those with many feminine but few masculine characteristics are feminine. People who show few masculine and feminine traits are designated as undifferentiated. Numerous studies indicate that androgynous persons are better adjusted psychologically, more popular, and have higher self-esteem than are masculine, feminine, or undifferentiated persons. In other research, individuals high in masculinity appear as well off as androgynous persons. These results suggest that it is the masculine component of androgyny (e.g., independence, confidence, self-reliance) that is most strongly associated with psychological well-being.
See also: GENDER-ROLE DEVELOPMENT
Bem, Sandra. "The Measurement of Psychological Androgyny."Journal of Consulting and Clinical Psychology 42 (1974):155-162.