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Richard A Lippa

Publications and source records attributed to Richard A Lippa.

10 recordsLinked to original sources
PubMed2006

The sex ratio of older siblings in non-right-handed homosexual men.

This study tested the prediction, based on prior research, that non-right-handed homosexual men will report fewer than expected older brothers. Participants were 2486 heterosexual and homosexual, right-handed and non-right-handed, male and female adults, representing five samples collected for various projects by the second author. Data on sibship composition, sexual orientation, and hand-preference were gathered in the original research using on-line (Internet) or self-administered paper-and-pencil questionnaires. The non-right-handed homosexual men reported 83 older brothers per 100 older sisters, which was significantly lower than the human sex ratio of 106 live-born males per 100 live-born females. In contrast, the right-handed homosexual men reported 125 older brothers per 100 older sisters, which was significantly higher than the expected ratio. One possible explanation of these results is that older brothers increase the odds of homosexuality in right-handed males but decrease the odds of homosexuality in non-right-handed males. A second possibility is that older brothers decrease the probability that non-right-handed homosexual males will be represented in survey research. The latter scenario could arise if the combination of some biological factor associated with older brothers and some biological factor associated with non-right-handedness is so toxic that it kills the fetus or predisposes the individual to a condition (e.g., mental retardation, major mental illness) that makes him less likely to be available for research recruitment at Gay Pride parades (etc.) than other members of the gay community.

Birth Order↗
PubMed2006

Is high sex drive associated with increased sexual attraction to both sexes? It depends on whether you are male or female.

If sex drive is a generalized energizer of sexual behaviors, then high sex drive should increase an individual's sexual attraction to both men and women. If sex drive energizes only dominant sexual responses, however, then high sex drive should selectively increase attraction to men or to women, but not to both, depending on the individual's sexual orientation. Data from three studies assessing a total of 3,645 participants show that for most women, high sex drive is associated with increased sexual attraction to both men and women. For men, however, high sex drive is associated with increased sexual attraction to only one sex or the other, depending on the individual's sexual orientation. These results suggest that the correlates of sex drive and the organization of sexual orientation are different for women and men.

Adult↗
PubMed2005

Finger lengths, 2D:4D ratios, and their relation to gender-related personality traits and the Big Five.

Finger lengths and the ratio of index finger to ring finger length (2D:4D) may be markers of gonadal hormone exposure. The current study investigated possible associations between absolute finger lengths, 2D:4D ratios, and gender-related personality traits in over 2000 participants. Regression analyses showed no associations between men's 2D:4D ratios and gender-related personality traits and weak associations between women's 2D:4D ratios and gender-related occupational preferences. Men's absolute finger lengths were weakly associated with self-ascribed masculinity, and women's absolute finger lengths were weakly associated with masculine occupational preferences. Big Five personality traits were assessed in a subsample of over 1000 participants. Analyses showed a weak positive association between 2D:4D and extraversion and a weak negative association between 2D:4D and openness to experience. Absolute finger lengths showed a weak negative association with agreeableness and a tendency to be associated with women's but not men's openness. Overall, associations between finger-length measures and personality were weak and inconsistent.

Adult↗
PubMed2005

A reanalysis of five studies on sexual orientation and the relative length of the 2nd and 4th fingers (the 2D:4D ratio).

Five studies have examined the relationship between sexual orientation and the relative lengths of the 2nd and 4th fingers (the 2D:4D ratio). Although differences have commonly been found between heterosexuals and homosexuals, the direction of the difference has not been consistent across studies. The original data from all five studies were reanalyzed in a search for possible explanations of the discrepancies. Because ethnicity is known to affect the 2D:4D ratio, the reanalysis focused on participants who identified themselves as White or Caucasian, the ethnic group that was most numerous in all of the studies. Age differences did not account for the discrepancies. Differences in variability within different groups were minor. One interesting result to emerge from the reanalysis was that the 2D:4D ratios for the homosexual groups were relatively similar across studies. It was the 2D:4D values for the heterosexual participants that varied most, particularly between the USA and the British studies, and these were responsible for many of the discrepancies in the conclusions across studies. The constancy of the 2D:4D ratio for the White homosexuals did not appear to extend to homosexuals of three other ethnicities, and there were also subpopulation differences related to right or left hands.

Adult↗
PubMed2005

Subdomains of gender-related occupational interests: do they form a cohesive bipolar M-F dimension?

In four studies, with a total of 1780 male and 2969 female participants, subdomains of masculine and feminine occupations were identified from sets of occupational preference items. Identified masculine subdomains included "blue-collar realistic" (e.g., carpenter), "educated realistic" (electrical engineer), and "flashy, risk-taking" (jet pilot). Feminine subdomains included "fashion-related" (fashion model), "artistic" (author), "helping" (social worker), and "children-related" (manager of childcare center). In all studies, principal components analyses of subdomain preference scales showed that masculine subdomains were bipolar opposites of feminine subdomains. This bipolar structure emerged in analyses conducted on combined-sex groups, high-school boys, high-school girls, men, women, heterosexual men, gay men, heterosexual women, and lesbian women. The results suggest that, although there are distinct masculine and feminine occupational subdomains, gender-related occupational preferences, nonetheless, form a replicable, cohesive, bipolar individual difference dimension, which is not an artifact of studying mixed-sex or mixed-sexual-orientation groups.

Adult↗
PubMed2005

Sexual orientation and personality.

The relation between sexual orientation and personality was examined in a meta-analysis with a total sample of 2,724 heterosexual men, 799 gay men, 157 bisexual men, 5,053 heterosexual women, 697 lesbian women, and 317 bisexual women. Self-ascribed masculinity-femininity (Self-M-F) and gender-related interests showed the largest heterosexual-homosexual differences (respective ds = .60 and 1.28 for men, and -1.28 and -1.46 for women) and the largest sex differences (respective ds = 2.83 and 2.65). Instrumentality and expressiveness showed much smaller heterosexual-homosexual and sex differences. Big Five traits showed a number of small-to-moderate heterosexual-homosexual and sex differences. Bisexual men were much more like gay men than like heterosexual men in their Self-M-F and gender-related interests, whereas bisexual women were intermediate between lesbian and heterosexual women. Homosexual participants were more variable on some gender-related traits than same-sex heterosexuals were. The gender inversion hypothesis-that gay men's traits tend to be somewhat feminized and that lesbians' traits tend to be somewhat masculinized-received considerable support. Results are discussed in terms of biological and psychosocial theories of gender and sexual orientation.

Bisexuality↗
PubMed2003

Handedness, sexual orientation, and gender-related personality traits in men and women.

This study assessed large numbers of heterosexual and homosexual men and women on handedness and gender-related personality traits. Initial analyses employed a dichotomous measure of handedness (right-handed vs. non-right-handed). For men and women combined, homosexual participants had 50% greater odds of being non-right-handed than heterosexual participants, a statistically significant difference. Homosexual men had 82% greater odds of being non-right-handed than heterosexual men, a statistically significant difference, whereas homosexual women had 22% greater odds of being non-right-handed than heterosexual women, a nonsignificant difference. When participants were classified into five graduated categories of handedness, both men and women showed significant homosexual-heterosexual differences in handedness distributions. Within groups, handedness showed a number of weak but statistically significant associations with sex-typed occupational preferences, self-ascribed masculinity, and self-ascribed femininity, but not with instrumentality or expressiveness. Rates of non-right-handedness were virtually identical for heterosexual men and women, suggesting that sex differences in handedness may result from higher rates of homosexuality in men.

Adult↗
PubMed2003

Are 2D:4D finger-length ratios related to sexual orientation? Yes for men, no for women.

The ratio of index and ring finger lengths (2D:4D) is thought to be a marker of prenatal androgen exposure. In a sample of over 2,000 participants, men had significantly lower 2D:4D ratios than women (d = .36 and .23 for right and left hands, respectively), and these results were consistent across ethnic groups. Heterosexual men had significantly lower (more male typical) 2D:4D ratios than gay men (d = .32 and .31 for right and left hands, respectively), and these results tended to be consistent across ethnic groups. Heterosexual and lesbian women showed no significant differences in 2D:4D ratios, after ethnicity was taken into account. The current findings add to evidence that prenatal hormonal factors may be linked to men's sexual orientation.

Adult↗
PubMed2002

Gender-related traits of heterosexual and homosexual men and women.

Two studies investigated the relation between sexual orientation and gender-related traits. Analyzing data from an Internet survey, Study 1 found that gay men and lesbians differed from same-sex heterosexuals most strongly on gender diagnosticity (GD) measures, which assess male- versus female-typicality of occupational preferences (effect sizes were 1.14 for men and 0.53 for women) and least strongly on instrumentality (I) and expressiveness (E). Study 2 found that GD measures showed large differences between 289 gay and 200 heterosexual men (d = 0.95) and between 296 lesbian and 435 heterosexual women (d = 1.32), whereas I and E showed much smaller differences. In Study 2 homosexual-heterosexual diagnosticity measures, computed from men's and women's occupational preferences, correlated very strongly with GD measures (r = 0.88 for men and 0.89 for women), indicating that occupational preference items that distinguished men from women also tended to distinguish heterosexual from homosexual individuals. LISREL 8 analyses showed that self-ascribed masculinity-femininity did not mediate the strong relation between sexual orientation and GD for men or for women.

Adolescent↗