### Conceptual Framework and Related Work
#### 2.3. Research Stream 3: Gender Differences in Personality  
Gender differences in personality are long acknowledged and several studies report gender differences in various personality traits. Here, we focus on the most important studies.  
[PERSON] published one of the most frequently cited meta-analyses about gender differences in personality [15]. Integrating the results of two decades of empirical research, he found that men scored higher than women in self-esteem and assertiveness, but lower in general anxiety.  
In another study (published in the same paper), [PERSON] [15] investigated, among others, gender differences in norms of several personality inventories. Therefore, the scales of the different personality inventories were grouped into nine groups/factors, which were named based on facet scales of the NEO Personality Inventory--Revised (NEO-PI-R). Afterwards these nine groups/factors were analyzed with regard to gender differences. [PERSON] [15] found no gender differences in impulsiveness (facet of neuroticism), activity (facet of extraversion), ideas (facet of openness (to experience)), and order (facetof conscientiousness). However, women scored slightly higher in gregariousness (facet of extraversion), and higher in scales of anxiety (facet of neuroticism) and trust (facet of agreeableness), as well as much higher on tender-mindedness (facet of agreeableness), whereas men scored higher (medium degree) on scales of assertiveness (facet of extraversion). However, [PERSON] [15] also stresses that moderating effects of the variable \"inventory\" have to be considered in result interpretation.  
Another important meta-analysis in the field of gender differences in personality is the cross-cultural study by [PERSON], [PERSON], and [PERSON] [14]. In detail, this meta-analysis investigated gender differences in the big five personality traits with six more narrow sub-facets for each of the five factors as assessed using the NEO-PI-R [14]. The analysis was conducted in samples from 26 cultures excluding clinical and occupational selection samples. Across the samples from the different cultures, they found rather modest, but significant gender differences in all facets of neuroticism and agreeableness with women scoring higher than men. In addition, women scored higher than men in warmth, gregariousness, and positive emotions, but lower in assertiveness and excitement seeking in most cultures (sub-facets of extraversion). Additionally, women scored higher than men in openness to aesthetics, feelings, and actions, but lower in openness to ideas. For the other factors (especially conscientiousness) and corresponding sub-facets no pattern of significant gender differences could be observed across cultures. It has to be noted that some of the effect sizes differed between countries [14].  
In addition to these important findings, especially gender differences in the HEXACO model of personality are of great importance for the present study. A recent study by [PERSON] and [PERSON] [16] investigated the psychometric properties of the HEXACO-PI-R (100-item version) in a sample of more than 100,000 participants. This study also analyzed gender differences. Results indicate that gender differences were found in the scales assessing honesty-humility and emotionality with women scoring higher than men [16]. In a study based on German participants (using the 60-item HEXACO questionnaire, HEXACO-60), women scored not only higher than men in honesty-humility and emotionality (thereby replicating the results by [PERSON] and [PERSON]), but also in agreeableness [17].