She's emotional. He's having a bad day: attributional explanations for emotion stereotypes.

People believe that women are the more emotional sex. This belief stems less from what men and women actually do than from the explanations given for their behaviors. In 2 studies, participants who were given situational information about the causes of emotional expression in target faces nonetheless more frequently judged feminine targets depicting emotions as "emotional" (i.e., a dispositional attribution for the emotional behavior), whereas they more frequently judged masculine targets as "having a bad day" (i.e., a situational attribution for the emotional behavior). These findings help explain the pervasive belief that women are more emotional when compared with men, even when the scientific veracity of this belief is questionable.