Correlations between HEXACO scales and EI and Humor Scales Europe’s Journal of Psychology, 6(3), pp. 9-33 www.ejop.org A Behav ioral Genetic Study of Relationships Between Humor Styles And The Six HEXACO Personality Factors Liv ia Veselka Department of Psychology, Univ ersity of Western Ontario, London, Canada Julie A. Schermer Management and Organizational Studies, Univ ersity of Western Ontario, London, Canada Rod A. Martin Department of Psychology, Univ ersity of Western Ontario, London, Canada Lynn F. Cherkas Tw in Research and Genetic Epidemiology Unit, King’s College London, UK Tim D. Spector Tw in Research and Genetic Epidemiology Unit, King’s College London, UK Philip A. Vernon Department of Psychology, Univ ersity of Western Ontario, London, Canada Abstract In this study, four humor styles (affiliative, self-enhancing, aggressive, self-defeating) were assessed in conjunction with a measure of the HEXACO model of personality, in order to gain greater insight into the etiology of these humor styles, and to situate them better in the framework of human personality. Participants were 664 monozygotic twin pairs and 522 dizygotic twin pairs from the United Kingdom w ho completed the Humor Styles Questionnaire and the HEXACO Personality I nventory. Univariate behavioral genetic analyses of the HEXACO revealed that individual differences in all of its dimensions were entirely attributable to additive genetic and non-shared environmental factors. Significant phenotypic correlations were found between many of the HEXACO factors http://www.ejop.org/ Europe’s Journal of Psychology 10 and the four humor styles, and bivariate behavioral genetic analyses revealed that these correlations were themselves accounted for entirely by correlated genetic and correlated non-shared environmental factors. Our study adds to the literature validating humor as a personality construct and assessing its relations to psychological well-being. Key words: Humor Styles, HEXACO model of personality, behavioral genetics, individual differences. Ov er the past sev eral years, there has been a dramatic shift in the w ay psychologists perceive humor. No longer v iew ed as a one-dimensional construct w ith consistently beneficial effects on physical and psychosocial w ell-being (e.g., Lefcourt, 2001; Martin, 2001), humor is now defined by a complex collection of traits that relate to both beneficial and deleterious outcomes (Martin, Puhlik -Doris, Larsen, Grey, & Weir, 2003). Most recently, the notion of humor styles—different w ays of expressing and using humor—has attracted a substantial empirical follow ing (Martin et al. , 2003). While a considerable portion of the emerging research has focused on better understanding these styles (e.g., Chen & Martin, 2007; Frew en, Brinker, Martin, & Dozois, 2008), v ery little is centered upon situating these styles w ithin v arious framew orks of human personality, and understanding their etiology in the context of these framew orks. Although some research is av ailable that examines humor styles in conjunction w ith the Big Fiv e model —the conv entional structure of human personality (e.g., Vernon, Martin, Sc her mer, & Mackie, 2008b)—studies assessing different and more elaborate structures of personality in relation to humor do not exist. Giv en that there is still a lack of consensus as to the true structure of personality (Lee & Ashton, 2004), and a continuing debate as to the number of higher -order dimensions that are needed to account for the v ariance in human personality (e.g., Veselka, Scher mer, Petrides, & Vernon, 2009, but see also Ashton, Lee, Goldberg, and de Vries, 2009), this restricted focus on the Big Fiv e model in personality research is not justified. With this in mind, the present study focuses on humor styles in relation to the HEXACO model —an alternativ e structure of personality comprising six rather than fiv e higher-order dimensions (Ashton & Lee, 2001). I n addition to reporting the first behav ioral genetic inv estigation of the HEXACO model, our study assesses the phenotypic correlations betw een the four humor styles and the six dimensions of this model. Further, by using data obtained from samples of tw ins, the study explores the extent to w hich obtained phenotypic correlations are attributable to correlated genetic and/or correlated env ironmental f actors. Behavioral Genetic Study 11 Development And Behavioral Genetic Investigation Of The HEXACO Model Throughout most of the 20th century, little consensus existed regarding the structure of human personality (Lee & Ashton, 2004). Sev eral models w ere put forth, offering v arying numbers of higher-order dimensions (e.g., Cattell, 1946; Eysenck, 1947; Wiggins, 1979), but w ith the exception of Eysenck’s P-E-N model, none gained an especially strong follow ing. By the 1980s, how ev er, the research community began to embr ace the idea that v ariation in human personality w as attributable to fiv e broad, roughly orthogonal dimensions (e.g., Goldberg, 1990; Saucier & Goldberg, 1996). Collectiv ely named the "Big Fiv e" (Goldberg, 1990), these factors comprised Extrav ersion, Agreeableness, Conscientiousness, Emotional Stability, and I ntellect/I magination. Costa & McCrae (1985 ) incorpor ated these fiv e dimensions into their personality questionnaire research, w hich led them to propose the existence of a Fiv e Factor Model of personality —a model v ery similar, though not identic al, to the Big Fiv e. Since the emergence of fiv e-factor models of personality, lexic al inv estigations carried out in a number of different languages hav e pointed to the potential existence of more elaborate personality models. Specifically, studies conducted in German (Angleitner & Ostendorf, 1989), Dutch (De Raad, 1992), Korean (Hahn, Lee, & Ashton, 1999), and French (Boies, Lee, Ashton, Pascal, & Nicol, 2001) hav e all noted the existence of a sixth fac tor of personality in addition to the conv entional fiv e—one that touches upon sincerity and modesty. Moreov er, studies carried out in Hungarian and I talian hav e confirmed a fiv e-factor solution of human personality structure, but hav e defined the fifth factor as reflecting integrity and trustw orthiness rather than the conv entional intellect/imagination (e.g., De Raad & Szir mak, 1994; Di Blas & Forzi, 1998). Taking these results into account, Ashton and Lee (2001) proposed the HEXACO model of personality, w hich is composed of six distinct dimensions. Fiv e of these dimensions are conceptually similar to those of the Big Fiv e (Extrav ersion, Agreeableness, Conscientiousness, Emotionality, and Openness to Experience). The sixth factor is labeled Honesty-Humility, and is defined by c haracteristics suc h as modesty, fairness, sincerity, and lack of greed (Lee & Ashton, 2004). Although behav ioral genetic analyses of the HEXACO model hav e not yet been undertaken, the Big Fiv e factors of personality hav e been inv estigated using this approach, the results of w hich shed some light on the potential etiology of at least some of the HEXACO dimensions. Across the great majority of the av ailable studies, there is a consensus that indiv idual differences in the Big Fiv e dimensions are attributable primarily to genetic and non-shared env ironmental factors (i.e., things Europe’s Journal of Psychology 12 w hich one tw in experiences but w hich their co-tw in does not experience; for example, hav ing different friends or being assigned to different teachers at school), w ith negligible contribution from the shared env ironment (i.e., things w hich both tw ins hav e in common; such as grow ing up in the same homes or going on v acations together w ith their parents) (e.g., Jang, Liv esley, & Vernon, 1996; Jang, McCrae, Angleitner, Riemann, & Liv esley, 1998; Loehlin, 1992; Riemann, Angleitner, & Strelau, 1997). Further research by Loehlin, McCrae, Costa, and John (1998) has show n that the Big Fiv e dimensions are all approximately equally heritable, and that these heritabilities do not differ signific antly across sexes. Most recently, Johnson, Vernon, and Feiler (2008) rev iew ed ev ery behav ioral genetic study of the Big Fiv e and related personality traits that had ev er been conducted: they found 145 such studies, c arried out betw een 1955 and 2007, and their rev iew confirmed that additiv e genetic and non-shared env ironmental factors accounted for the majority of the v ariance in these traits. Their rev iew , and the other inv estigations referred to abov e, how ever, did not include the sixth HEXACO factor of Honesty-Humility, w hich does not hav e a Big Fiv e analogue, and therefore information on the genetic and/or env ironmental etiology of this factor is c urrently not av ailable. Humor Styles And Their Personality Correlates Humor styles w ere first introduced in early psychological research, w here it w as observ ed that certain uses of humor (e.g., perspectiv e-taking, affiliativ e) w ere linked to positiv e psychological functioning, w hereas other for ms of humor (e.g., sarcastic, dispar aging) w ere associated w ith more negativ e outcomes (e.g., Allport, 1961; Freud, 1928; Maslow , 1954). How ev er, it w as Martin et al. (2003) w ho formally proposed the existence of distinct humor styles—tw o positiv e and tw o negativ e— after noting that prev ious empirical studies had found only w eak associations betw een measures of humor and mental health v ariables (e.g., Kuiper & Martin, 1998; Thorson, Pow ell, Sar many -Schuller, & Hampes, 1997), and inconsistent relations betw een humor and physic al health constructs (Martin, 2001). Specifically, Martin et al. (2003) proposed the existence of affiliativ e, self-enhancing, aggressiv e, and self- defeating styles of humor. Affiliativ e humor is a non-hostile for m of humor that is intended to amuse others as a w ay of facilitating relationships. Self-enhancing humor sees indiv iduals finding amusement in life's hardships and incongruities, allow ing them to maintain a humorous outlook ev en w hen faced w ith adversity. Aggressiv e humor is a form of dispar aging humor that entails sarcasm and put-dow ns, and w hich can be used to manipulate others. Finally, self-defeating humor inv olv es saying funny things at one's Behavioral Genetic Study 13 ow n expense in order to gain approv al, and laughing along w ith others w hen one is being ridic uled. Only the affiliativ e and self-enhancing humor styles hav e been linked positiv ely to psychological w ell-being, w hereas aggressiv e and self-defeating humor styles tend to be negativ ely associated w ith w ell-being and relationship satisfaction (e.g., Kazarian & Martin, 2006; Martin, 2007; Martin et al., 2003). I n dev eloping the theory behind these humor styles, Martin et al. (2003) also assessed associations betw een the styles and the Big Fiv e factors of personality. The authors found that the affiliativ e and self-enhancing humor styles w ere positiv ely associated w ith Extrav ersion and Openness, w ith self-enhancing humor further correlating positiv ely w ith Agreeableness. Additionally, significant negativ e correlations w ere noted betw een the aggressiv e and self-defeating humor styles and the factors of Agreeableness and Conscientiousness. Finally, signific ant relations betw een Neuroticism and some of the humor styles w ere observ ed, w ith the self-enhancing humor styles correlating negativ ely w ith this dimension, and the aggressiv e and self - defeating styles correlating positiv ely. These findings w ere largely replicated by Vernon, Martin, Scher mer, and Mackie (2008). Giv en the relativ ely nov el status of the HEXACO model, it has not yet been assessed in ter ms of its relations to the humor styles. While the existing research examining the correlations betw een the Big Fiv e dimensions and the four styles of humor does shed some light on the manner in w hich fiv e of the six HEXACO factors w ould be expected to relate to the humor styles, this research does not prov ide any clues about the HEXACO f actor of Honesty-Humility. Prev ious w ork that has noted a positiv e association betw een fairness and w ell-being (e.g., Sparr & Sonnentag, 2008; Tortia, 2008) suggests that a positiv e relation betw een Honesty-Humility and the tw o positiv e humor styles w ill be found, because the latter hav e also been linked to w ell - being (e.g., Kazarian & Martin, 2006; Martin et al., 2003). I t might also imply negativ e correlations betw een this HEXACO dimension and the tw o negativ e humor styles, w hich tend to be negativ ely associated w ith mental health (e.g., Martin et al., 2003). These suggestions are at this point quite spec ulativ e, how ev er, and require empirical inquiry. Previous Behavioral Genetic Analyses Of Humor Styles Early research on the behav ioral genetic origins of v ariation in humor focused on humor appreciation, w hich assessed the extent to w hich participants perceiv ed target material as being funny (Vernon, Martin, Scher mer, Cherkas, & Spector, 2008a). Results from these studies indicated that indiv idual differences in humor Europe’s Journal of Psychology 14 appreciation w ere primarily attributable to shared and non-shared env ironmental factors (e.g., Cherkas, Hochberg, MacGregor, Snieder, & Spector, 2000; Nias & Wilson, 1977; Wilson, Rust, & Kasriel, 1977). Later assessments of humor, how ev er, noted that the construct of humor appreciation, though legitimate, w as not related to one’s ability to produce or to engage in humor, and w as therefore not a v alid representation of sense of humor or humor style (Köhler & Ruch, 1996). As such, subsequent behav ioral genetic research on humor shifted to assess indiv idual differences in sense of humor, w hich represents the extent to w hich indiv iduals notice and enjoy humor, maintain a cheerful outlook, and laugh and smile frequently (e.g., Martin, 1996). Findings from these studies suggested that v ariation in sense of humor is partly heritable (Loehlin & Nic hols, 1976), and attributable to a combination of genetic and non-shared env ironmental f actors (e.g., Manke, 1998). Most recently, behav ioral genetic research on humor has begun to focus on humor styles. Vernon et al. (2008a) carried out the seminal study assessing the potential etiology of humor styles, and found that indiv idual differences in all of the styles w ere accounted for by genetic, shared, and non-shared env ironmental factors. Specifically, they observ ed that the affiliativ e and self-enhancing humor styles w ere primarily influenced by genetic and non-shared env ironmental effects, w ith only a negligible contribution from shared env ironmental factors. Variation in the aggressiv e and self-defeating styles, on the other hand, w as mainly attributable to shared and non-shared env ironmental f actors. The researchers f urther carried out a biv ariate behav ioral genetic inv estigation to assess the extent to w hich phenotypic correlations betw een the four humor styles and the Big Fiv e factors of personality w ere attributable to common genetic and/or env ironmental factors. Results rev ealed that the obtained phenotypic correlations w ere entirely accounted for by correlated genetic and correlated unique env ironmental factors. No significant shared env ironmental correlations w ere noted betw een the v ariables. These results suggest that both the humor styles and the Big Fiv e dimensions share some of the same genetic and non-shared env ironmental deter minants. Biv ariate behav ioral genetic studies that employ humor style v ariables hav e not yet been c arried out in conjunction w ith personality structures other than the Big Fiv e, meaning that shared etiological fac tors underlying the HEXACO dimensions and the four humor styles hav e not yet been assessed. The w ork of Vernon et al. (2008a) prov ides a good basis for this type of research, giv en that fiv e factors of the HEXACO model are v ery similar to the Big Fiv e, and may therefore yield similar results. The Honesty-Humility factor, how ev er, has not been explored in relation to humor styles, and w ill therefore make a nov el contribution to this area of research. Behavioral Genetic Study 15 Present Study The purpose of the present study w as to gain a greater understanding of humor styles by examining them in relation to an alternativ e model of personality—that of the HEXACO. I n this study, humor styles w ere measured using the Humor Styles Questionnaire (HSQ; Martin et al., 2003) and the HEXACO fac tors w ere assessed using the short for m HEXACO-60 (Ashton & Lee, 2009). Univ ariate behav ioral genetic analyses w ere first employed to inv estigate the extent to w hich indiv idual differences in the HEXACO fac tors can be accounted for by genetic and/or env ironmental factors—findings that are important for better understanding results at the biv ariate lev el (Plomin, 1986). Phenotypic correlations betw een the four humor styles and the six HEXACO dimensions w ere then computed to deter mine the relations betw een these sets of constructs, and to situate the humor styles into an alternativ e pers onality model other than the Big Fiv e. Finally, biv ariate behav ioral genetic analyses w ere carried out to assess the extent to w hich any obtained phenotypic correlations are attributable to common genetic and/or env ironmental factors. These analyses w ill prov ide a deeper glimpse into the potential etiology of humor styles in relation to personality structure dimensions. I n the univ ariate behav ioral genetic assessment of the HEXACO model, it w as predicted that v ariation in all six dimensions w ould be accounted for by genetic and non-shared env ironmental factors. As noted abov e, prev ious studies of the Big Fiv e factors of personality, w hich are roughly analogous to fiv e of the six HEXACO factors, exhibit this pattern of results. Although no prev ious etiologic al w ork has been done on the v ariables char acterizing the sixth fac tor of Honesty-Humility, or on the dimension itself, it w as expected that it w ould behav e as most personality v ariables do—show ing primarily genetic and non-shared env ironmental effects (Jo hnson et al., 2008). I n terms of phenotypic correlations, it w as predicted that the positiv e and negativ e styles of humor w ould exhibit different patterns of associations w ith the HEXACO dimensions. Specifically, based on prev ious findings w ith the Big Fiv e model (e.g., Martin et al., 2003; Vernon et al., 2008b), it w as expected that affiliativ e and self- enhancing humor styles w ould correlate positiv ely w ith the HEXACO factors of Extrav ersion and Openness. I t w as also expec ted that aggressiv e and self-defeating humor w ould correlate negativ ely w ith Agreeableness and Conscientiousness, and positiv ely w ith Emotionality—the HEXACO analogue to the Big Fiv e’s Neuroticism. Finally, an additional positiv e correlation w as predicted betw een Agreeableness and self-enhancing humor. With regard to the Honesty-Humility dimension, it is Europe’s Journal of Psychology 16 plausible that this might correlate positiv ely w ith the tw o positiv e humor styles, giv en that these humor styles as w ell as the Honesty-Humility f actor all show associations w ith psychosocial w ell-being (e.g., Martin et al., 2003). By the same token, it w as expected that the tw o negativ e humor styles w ould show negativ e correlations w ith Honesty-Humility, because they tend to be negativ ely associated w ith w ell-being (e.g., Kazarian & Martin, 2006). Finally, it w as predicted that the biv ariate behav ioral genetic analyses w ould show that the phenotypic correlations betw een the humor styles and the HEXACO dimensions w ould be accounted for by correlated genetic and correlated non- shared env ironmental factors. This prediction is especially salient for the HEXACO dimensions that are similar to those of the Big Fiv e, giv en that the correlations betw een these Big Fiv e dimensions and the four humor styles hav e prev iously been show n to be attributable to genetic and unique env ironmental effects. Because there is presently no large body of research dealing w ith the personality correlates of the Honesty-Humility dimension of the HEXACO, predic ting its behav ior under biv ariate behav ioral genetic inv estigation w ith the four humor styles is less straightforw ard. I t w as, how ever, suggested that any observ ed correlations betw een the humor styles and Honesty-Humility w ould also be accounted for by correlated genetic and non-shared env ironmental f actors, based on the pattern of results obtained w ith other higher-order personality dimensions (e.g., Vernon et al., 2008a). Method Participants Participants in the present study w ere 1,186 pairs of tw ins: 664 monozygotic (MZ) tw in pairs (604 female pairs and 60 male pairs) and 522 dizygotic (DZ) tw in pairs (482 female pairs and 40 male pairs). Although there are many more females than males in our samples, this is not uncommon in research w ith tw ins (Lykken, McGue, & Tellegen, 1987) but is particularly exaggerated i n our sample bec ause the original focus of research w ith these tw ins w as the genetics of osteoporosis and osteoarthritis: conditions w hich are much more common among females. Tw ins ranged in age from 18 to 92 years (M = 56.4, SD = 13.2), and w ere participants in ongoing studies conducted by the Department of Tw in Research and Genetic Epidemiology (DTR) at King’s College London in England. This department mails out questionnaires to approximately 9,000 indiv idual tw ins each year. The zygosity of participatin g tw ins has been established by means of genome scans (100% accurate), DNA tests (99.5% accurate), or by responses to the ―Peas in a pod‖ zygosity questionnaire (95% Behavioral Genetic Study 17 accurate). Tw ins taking part are not compensated for their participation. Materials Humor Styles Questionnaire (HSQ). I ndiv idual differences in four humor styles (affiliativ e, self-enhancing, aggressiv e, and self-defeating) w ere assessed using the 32-item HSQ (Martin et al., 2003). Each item of the HSQ presents a self -reflectiv e statement pertaining to humor. Participants indic ate the extent to w hich they agree w ith each statement using a 7-point Likert Scale (w here 1 = totally disagree and 7 = totally agree). Example items include: "I enjoy making people laugh" (affiliativ e); "I f I 'm by myself and I `m feeling unhappy, I make an effort to think of something funny to cheer myself up" (self-enhancing); "I f I don't like someone, I often use humor or teasing to put them dow n" (aggressiv e); and "Letting others laugh at me is my w ay of keeping my friends and f amily in good spirits ‖ (self-defeating). Reliabilities of the scales are .81 for self-enhancing humor, 80 for affiliativ e and self-defeating humor, and .77 for aggressiv e humor. HEXACO Personality Inventory. Participants also completed the 60 -item HEXACO Personality I nv entory (HEXACO-60; Ashton & Lee, 2009), w hich assesses indiv idual differences in six personality dimensions —conscientiousness, extrav ersion, agreeableness, openness to experience, emotionality, and honesty-humility. Participants responded to self-reflectiv e statements on this questionnaire v ia a 5- point Likert scale (w here 1 = strongly disagree and 5 = strongly agree). I nternal consistency reliabilities for the scales hav e been reported to range betw een .77 and .80 in a sample of college students and betw een .73 and .80 in a community sample (Ashton & Lee, 2009). Procedure I n Nov ember 2008, approximately 9000 indiv idual tw ins w ere mailed a questionnaire w hich included the HEXACO-60 as w ell as additional questions that are not pertinent to the present study. Approximately 5000 indiv idual tw ins (56%) returned the completed questionnaires and, of these, a total of 3012 w ere complete same -sex pairs (837 MZ pairs and 669 DZ pairs). Tw o years earlier, the questionnaire mail-out include d the HSQ, and 664 MZ and 522 DZ tw in pairs had completed this as w ell as the HEXACO. Tw ins completed the questionnaires at their ow n time in their homes, and returned them to the DTR. Europe’s Journal of Psychology 18 Analyses Ev en though the majority of the participating tw ins completed the questionnaires in full, there w ere rare instances in w hich an item w as left blank. I n these cases, the missing infor mation w as replaced w ith the av erage of the item’s Likert scale. Subsequently, the items of the HSQ w ere reduced to four scores reflec ting the four humor styles being assessed. Similarly, the items of the HEXACO-60 w ere conv erted to six unique scores corresponding to the six dimensions of the HEXACO model of personality. Prior to analysis, all data w ere corrected for age and sex v ia the regression approach proposed by McGue and Bouchard (1984). This controls for any age or sex differences w hich might exist (see below ) and is particularly important giv en the much greater number of females than males in our sample. When conducting univ ariate behav ioral genetic analyses, members of each tw in pair w ere randomly designated as ― Tw in 1‖ or ― Tw in 2‖ and betw een-tw in correlations w ere then calculated separately for MZs and DZs. Structural equation model-fitting w as then c arried out using the softw are package Mx (Neale, Boker, Xie, & Maes, 2006) to estimate the extent to w hich indiv idual differences can be attributed to additiv e genetic (A), shared env ironmental (C), and non-shared env ironmental factors (E). Although it is possible to fit reduced models to data (e.g., AE, CE), w e did not do so in the present analysis due to the recommendations of Sulliv an and Eav es (2002). These researchers hav e suggested that such reduced models yield ov ersimplified rather than more parsimonious results, w hereas full ACE models prov ide accurate estimates for discrete traits. Biv ariate BG analyses w ere also performed using Mx. These analyses estimate the extent to w hich observ ed phenotypic correlations betw een v ariables are attributable to common genetic and/or common env ironmental influences by examining the cross-correlations w ithin tw in-pairs (i.e., the correlation betw een one tw in’s score on one v ariable w ith their co-tw in’s score on another v ariable) using the method of Cholesky or triangular factor analysis (Neale & Cardon, 1992). I n conducting these analyses, a f ull ACE model w as tested as w ell as reduced AE and CE models: the model w ith the low est chi-square v alue and low est AI C v alue is chosen as the best fitting model. For each of the correlations reported in Table 2 below , an AE model w as found to hav e the best fit, resulting in estimates of genetic (rg) and non-shared env ironmental (re) correlations. Behavioral Genetic Study 19 Results Giv en the large size of our samples, not surprisingly significant sex differences w ere found on most of the v ariables. I n fact, of the six HEXACO and the four HSQ v ariables, significant differences existed on all except conscientiousness and openness. Females obtained signific antly higher scores on honesty-humility, emotionality, and agreeableness (all 2-tailed p < .0001); males scored significantly higher than females on extrav ersion (p < .05, 2-tailed) and on all four HSQ humor styles (all 2-tailed p < .05). These findings are not atypic al, particularly for emotionality, honesty, and aggressiv e humor (e.g., Ashton & Lee, 2009; Chen & Martin, 2007; Kazarian & Martin, 2006), although it also bears noting that the actual mean differences betw een males and females w ere quite small. We also found significant correlations betw een age and all HEXACO and HSQ v ariables except openness, although these w ere again quite small, ranging from .04 for age and self- enhancing humor to -.21 for age and affiliativ e humor. Though small, these significant age and sex effects nonetheless need to be (and w ere) controlled for before conducting the analyses that follow . Tw in correlations and parameter estimates deriv ed from univ ariate behav ior genetic analyses of the six HEXACO dimensions are presented in Table 1. For all of the dimensions, MZ correlations w ere substantially larger than DZ correlations, implying the existence of genetic effects. Model-fitting results clarified these effects by rev ealing that indiv idual differences in the higher -order HEXACO f actors can be accounted for entirely by genetic and non-shared env ironmental effects. Genetic effects w ere particularly strong for the HEXACO dimension of Openness to Experience (.59) w hile Conscientiousness exhibited the low est contribution from genetic fac tors (.32). This is the first report on the heritability of t he HEXACO dimensions and it is of interest that Honesty– the dimension unique to the HEXACO model– show s a similar degree of genetic influence (.35) as sev eral of the other more traditional dimensions. Table 1 Twin Correlations and Parameter Estimates f or the HEXACO Dimensions Variables Correlations Parameter estimates (95% CI ) M Z DZ a2 c2 e2 Honesty .36 .14 .35 (.22 to .40) .00 (.00 to .11) .65 (.60 to .71) Emotionality .49 .23 .48 (.30 to .00 (.00 to .52 (.48 to .58) Europe’s Journal of Psychology 20 .52) .15) Extrav ersion .48 .14 .45 (.36 to .50) .00 (.00 to .07) .55 (.50 to .60) Agreeableness .40 .12 .37 (.28 to .42) .00 (.00 to .07) .63 (.58 to .68) Conscientiousn ess .33 .16 .32 (.14 to .38) .00 (.00 to .16) .68 (.62 to .74) Openness .59 .28 .59 (.48 to .63) .00 (.00 to .10) .41 (.37 to .46) Note. a2 = additiv e genetic effects; c2 = shared env ironmental effects; e2 = non- shared env ironmental effects; CI = confidence interv al. All effects w hose confidence interv als do not include zero are significant at the .05 lev el. The results of univ ariate genetic analyses of the HSQ w ithin this sample hav e been reported prev iously (Vernon, Martin, Sc her mer, Cherkas, & Spector, 2008). I n brief, in this UK sample of tw ins indiv idual differences in all four humor styles w ere found to be attributable to additiv e genetic and non-shared env ironmental factors, w ith heritability estimates ranging betw een .34 (self-defeating humor ) and .49 (affiliativ e humor). Phenotypic correlations (rp) betw een the HSQ and the HEXACO -60 are show n in Table 2. From these correlations, it is ev ident that the affiliativ e and self -enhancing humor styles are positiv ely associated w ith HEXACO`s Extrav ersion and Openness to Experience and to a lesser extent w ith Conscientiousness. Both positiv e humor styles are also negativ ely correlated w ith the model`s Emotionality dimension. Affiliativ e humor also show s a small but significant negativ e correlation w ith the Honesty- Humility factor, w hile self-enhancing humor correlates positiv ely w ith Agreeableness. As w ould be expected, aggressiv e and self-defeating humor styles are negativ ely related to HEXACO`s Honesty-Humility, Agreeableness, and Conscientiousness factors. Self-defeating humor show s a positiv e correlation w ith the Emotionality dimension, w hereas aggressiv e humor has a small but significant negativ e Behavioral Genetic Study 21 correlation. Self-defeating humor also has a small but significant negativ e correlation w ith Extrav ersion. Table 2 Phenotypic (rp,) Genetic (rg) and Environmental (re) Correlations with Conf idence Interval Values between the HEXACO Dimensions and the Humor Styles Measured by the HSQ HSQ Sc ales Affiliativ e Self-enhancing Aggressiv e Self-defeating H Rp = -.06* rg = -.10 (-.23 to .02) re = -.03 (-.10 to .04) rp = .01 rg = -.03 (-.17 to .11) re = .02(-.05 to .09) rp = -.33* rg = -.55 (-.43 to - .76) re = -.18 (-.12 to - .25) rp = -.16* rg = -.21 (-.08 to - .35) re = -.12 (-.05 to - .19) Em rp = -.09* rg = -.09 (-.19 to .02) re = -.10 (-.02 to .18) rp = -.17* rg = -.26 (-.14 to - .37) re = -.11 (-.04 to - .18) rp = -.07* rg = -.20 (-.09 to - .31) re = .03 (-.04 to .10) rp = .15* rg = .14 (.03 to .25) re = .13 (.06 to .20) Ex rp = .42* rg = .61(.53 to .69) re = .26 (.19 to .32) rp = .39* rg = .60 (.50 to .70) re = .23 (.16 to .29) rp = .03 rg = .09 (-.02 to .20) re = -.01 (-.07 to .07) rp = -.08* rg = -.12 (-.23 to .01) re = -.04 (-.11 to .03) A rp = -.01 rg = -.10 (-.22 to .01) re = .07 (-.01 to .14) rp = .19* rg = .16 (.04 to .29) re = .19 (.12 to .25) rp = -.27* rg = -.47 (-.36 to - .59) re = -.13 (-.06 to - .20) rp = -.06* rg = -.14 (-.02 to - .27) re = -.01 (-.07 to .07) C rp = .10* rg = .25 (.13 to .38) re = -.02 (-.09 to .05) rp = .06* rg = .08 (-.06 to .22) re = .03 (-.04 to .10) rp = -.16* rg = -.18 (-.05 to - .31) re = -.15 (-.08 to - .22) rp = -.15* rg = -.19 (-.06 to - .32) re = -.12 (-.05 to - .19) Europe’s Journal of Psychology 22 O rp = .20* rg = .29 (.21 to .38) re = .09 (.02 to .16) rp = .17* rg = .28 (.19 to .38) re = .06 (-.01 to .14) rp = -.05 rg = -.04 (-.14 to .06) re = -.06 (-.13 to .01) rp = .03 rg = .11 (.07 to .21) re = -.06 (-.13 to .01) Note. H = Honesty-Humility. Em = Emotionality. Ex = Extr av ersion. A = Agreeableness. C = Conscientiousness. O = Openness to Experience. rg = genetic correlation. rc = shared env ironmental correlation. re = non-shared env ironmental correlation. Numbers appearing in brackets represent the 95% confidence interv al v alues. All correlations w hose confidence interv als do not include zero are signific ant at the .05 lev el. *p < .01, tw o-tailed. The biv ariate model-fitting results are also reported in Table 2 and rev eal that the phenotypic correlations betw een the HEXACO and the HSQ are entirely attributable to correlated genetic (rg) and correlated non-shared env ironmental (re) factors. For the positiv e humor styles, significant genetic correlations can be seen betw een affiliativ e humor and Extrav ersion, Conscientiousness, and Openness to Experience, and betw een self-enhancing humor and Emotionality, Extrav ersion, Agreeableness, and Openness to Experience. For the negativ e humor styles, significant genetic correlations exist betw een aggressiv e humor and Honesty-Humility, Emotionality, Agreeableness, and Conscientiousness, and betw een self-defeating humor and all HEXACO dimensions except Extrav ersion. Sev eral of the genetic correlations are quite large (e.g., .61 and .60 betw een extrav ersion and affiliativ e and self -enhancing humor, respectiv ely, and -.55 betw een Honesty-Humility and aggressiv e humor), indicating substantial ov erlap betw een the genes that contrib ute to indiv idual differences on eac h of these v ariables. I n terms of env ironmental correlations, significant non-shared env ironmental associations exist betw een affiliativ e humor and Extrav ersion and Openness to Experience, as w ell as betw een self-enhancing humor and Extrav ersion and Agreeableness. Significant non-shared env ironmental correlations can also be seen betw een aggressiv e humor and Honesty-Humility, Agreeableness, and Conscientiousness, and betw een self-defeating humor and Honesty-Humility, Emotionality, and Conscientiousness. The great majority of the env ironmental correlations w ere somew hat to substantially smaller than the genetic correlations betw een the same pairs of v ariables. No shared env ironmental correlations w ere found betw een any of the v ariables. Behavioral Genetic Study 23 Discussion I n addition to reporting the first behav ioral genetic inv estigation of the HEXACO model, the present study had tw o main goals: to deter mine the associations betw een the four humor styles and the HEXACO dimensions, in order to situate the humor styles in a more comprehensiv e personality structure, and to assess the potential etiology of humor styles in the context of this structure. These goals w ere addressed through a correlational analysis coupled w ith univ ariate and biv ariate behav ioral genetic model-fitting analyses. As predicted, indiv idual differences in the six HEXACO dimensions w ere entirely attributable to genetic and non-shared env ironmental factors. I n part, these findings replicate the results of past studies of the Big Fiv e model (e.g., Jang et al., 1996; Johnson et al., 2008; Riemann et al., 1997), the dimensions of w hich are roughly analogous to fiv e of the six HEXACO factors. These studies hav e reported that v ariance in the Big Fiv e dimensions is largely accounted for by genetic and unique env ironmental factors. Beyond replicating these findings, and extending them to the HEXACO model, how ev er, the present study also confir med that the sixth HEXACO dimension of Honesty-Humility also behav es in the same manner as do its other dimensions. As suc h, the present study further v alidates the HEXACO model by demonstr ating that all of its dimensions share a similar etiology. Moreov er, it is likely that the heritabilities found in our study are low er -bound estimates because w e used the short-for m of the HEXACO Personality I nv entory w hich is not as reliable as longer measures. Many of the phenotypic correlations observ ed betw een the HEXACO dimensions and the four humor styles confir med our predictions, and echoed the results of prev ious studies examining relationships betw een humor styles and the Big Fiv e. These correlations are also likely to be underestimates bec ause of the tw o year gap betw een subjects’ completing the HSQ and the HEXACO-60. With regard to the prosocial humor styles (affiliativ e, self-enhancing), positiv e correlations w ere noted betw een these and HEXACO’s Extrav ersion and Openness factors, and an additional positiv e correlation w as observ ed betw een self-enhancing humor and HEXACO’s Agreeableness dimension. Giv en that prev ious studies w ith the Big Fiv e hav e found similar associations (e.g., Martin et al., 2003; Vernon et al., 2008b), and that the tw o prosocial humor styles or related measures hav e been linked to social intimacy (Martin et al., 2003), creativ ity (e.g., Oral, 2006; Wycoff & Pryor, 2003) and trust (Hampes, 1999), w hich are characteristics of Extrav ersion, Openness, and Europe’s Journal of Psychology 24 Agreeableness, respectiv ely (Lee & Ashton, 2004), these correlations are not surprising. With regard to the tw o deleterious styles of humor (aggressiv e and self-defeating), these w ere found to correlate negativ ely w ith HEXACO Agreeableness and Conscientiousness, as w e had predicted. Similar findings hav e been reported in prev ious studies of humor styles and the Big Fiv e (e.g., Martin et al., 2003; Vernon et al., 2008b). Other studies hav e further substantiated these findings by noting negativ e relations betw een these tw o humor styles and related measures, and the constructs of trust (e.g., Hampes, 1999) and perfectionism (e.g., Fry, 1995) - characteristics that help to define the HEXACO f actors of Agreeableness and Conscientiousness, respec tiv ely. I n addition to these predicted correlations, other associations w ere observed that had not been noted in prev ious studies of humor styles. For example , negativ e correlations w ere found betw een the tw o positiv e humor styles and the HEXACO dimension of Emotionality, w hich is an analogue to the Big Fiv e dimension of Neuroticism. Prev ious studies hav e found this type of correlation betw een self- enhancing humor and Neuroticism, but hav e not done so w ith affiliativ e humor (e.g., Martin et al., 2003; Vernon et al., 2008b). How ev er, giv en that both of these prosocial humor styles hav e been linked to psychologic al w ell-being (Martin et al., 2003), w hereas Emotionality reflects such negativ e affect traits as anxiety, fearfulness, and dependence (Lee & Ashton, 2004), the correlations w e obtained hold conceptual v alidity. Moreover, although w e expected that both negativ e humor styles w ould correlate positiv ely w ith Emotionality, giv en the findings of prev ious studies linking the Big Fiv e’s Neuroticism to aggressiv e and self-defeating humor, only self-defeating humor exhibited this positiv e relation. I n our study, aggressiv e humor actually correlated negativ ely w ith Emotionality. I t can, how ever, be argued that this pattern of correlations makes sense, in light of the manner in w hich HEXACO’s Emotionality is defined. Specific ally, because Emotionality is characterized by qualities suc h as fearfulness, anxiety, and dependence (Lee & Ashton, 2004), it may be the case that those w ho employ self-defeating humor are high on the Emotionality dimension due to their insecurity (high anxiety) and excessiv e concern about close relationships w ith others (high dependence). On the other hand, those exhibiting an aggressiv e humor style may be unconcerned about har ming the feelings of others (low anxiety), and may be motiv ated to push others aw ay (low dependence). Behavioral Genetic Study 25 I n addition to substantially replic ating many of the correlations prev iously noted betw een the Big Fiv e and humor styles, thereby confir ming the HEXACO model’s v alidity as a higher-order personality framew ork, we also observed sev eral correlations betw een the humor styles and HEXACO’s sixth dimension of Honesty - Humility. Specific ally, as expected the tw o negativ e humor styles exhibited negativ e correlations w ith Honesty-Humility. Because Honesty-Humility is defined as a prosocial dimension (Lee & Ashton, 2004), w hile aggressiv e and self-defeating humor hav e more socially av ersiv e overtones (Martin et al., 2003), these obtained negativ e correlations are reasonable, suggesting that those w ho employ deleterious humor styles – particularly aggressiv e humor - are likely to be less sincere, less modest, less fair, and more greedy than those w ho do not. A small yet significant negativ e correlation w as also found betw een affiliativ e humor and Honesty-Humility factor, w hich w e had not predicted. This correlation may indicate that w hile high scorers on Honesty-Humility tend to exhibit modesty and av oid flattery, those w ho use affiliativ e humor may sometimes employ a certain amount of insincere adulation in an effort to secure friendships and, as a result, may score low er on the Honesty-Humility dimension. We acknow ledge that this suggestion is spec ulativ e and that it requires further inv estigation. Finally, w ith regard to the multiv ariate behav ioral genetic analyses, w e found that the phenotypic correlations discussed abov e w ere entirely attributable in the first instance to correlated genetic factors and secondarily to correlated non-shared env ironmental factors, as predicted. These results suggest that the four humor styles and the six HEXACO dimensions share many ov erlapping genetic and unique env ironmental deter minants. These results also add to the existing literature by show ing that all of the HEXACO dimensions, including the Honesty-Humility factor that has not been explored prev iously using multiv ariate behav ioral genetic methodology, behav e as other higher-order dimensions of personality hav e done (e.g., Vernon et al., 2008a). To put our results into a broader context, it w ill be infor mativ e to look at studies of relationships betw een humor styles, the Big Fiv e, and trait Emotional I ntelligence (trait EI ) (e.g., Grev en, Chamorro-Premuzic, Arteche, & Furnham, 2008; Vernon, Villani, Scher mer, Kirilov ic, Martin, Petrides, et al., 2009, Vernon, Villani, Scher mer, & Petrides, 2008). The construct of trait EI comprises a collection of self-perceiv ed emotion- related dispositions and abilities. I n its global for m, it is negativ ely associated w ith Neuroticism and positiv ely associated w ith the other Big Fiv e factors (Vernon et al., 2008c ) - correlations w hich indicate its prosocial nature, w hile also situating it w ithin the structure of human personality. I n addition, trait EI correlates positiv ely w ith the Europe’s Journal of Psychology 26 tw o prosocial humor styles, and negativ ely w ith the tw o deleterious humor style s (e.g., Grev en et al., 2008; Vernon et al., 2009). Giv en these links, it is possible that trait EI contributes to determining w hy people adopt certain humor styles. Specifically, the characteristic use of positiv e humor styles may require high trait EI , giv en that indiv iduals need to understand the emotions of others, and to manage their ow n emotions if they w ant to create friendships and ov ercome adv ersity (Vernon et al., 2009). On the other hand, those w ho employ negativ e humor styles may be low er on trait EI , being emotionally unaw are or emotionally self-har ming in their use of humor (Vernon et al., 2009). If this is the case, then it is unsurprising that, in the present study, the positiv e humor styles w ere linked to HEXACO’s Extrav ersion, Openness, and Agreeableness - dimensions that are associated w ith high trait EI (Vernon et al., 2008c ). This may also account for the negativ e correlations we found betw een the negativ e humor styles and Honesty-Humility, w hich is defined by constructs suc h as forgiv eness and f airness w hich in turn reflect high trait EI . Further support linking humor styles and the HEXACO model to trait EI comes from research on the so-c alled general fac tor of personality (GFP) - a super-dimension that has been proposed to sit at the apex of the personality hierarchy and to subsume all personality traits in a manner similar to Spe ar man’s g in the domain of mental abilities (Ruhston, Bons, & Hur, 2008). Using principal components analyses, Veselka, Scher mer, Petrides, Cherkas, Spector, & Vernon (2009) extracted a general factor from the six HEXACO and four trait EI factors; Emotionality loaded negativ ely on this factor I n addition, a general factor has been extracted from the Big Fiv e factors, the four humor styles, and four factors of trait EI (Rushton, Bons, Ando, Hur, Irw ing, Vernon, et al., 2009). From these results, it may be that positiv e humor styles, trait emotional intelligence, and the HEXACO factors (including low Emotionality) hav e slow ly ev olved ov er time in concert w ith one another bec ause they hav e helped to contribute to social dominance and reproduc tiv e success. I t should be noted, how ev er, that this proposition is debatable, particularly giv en the lack of consensus that surrounds the existence of a GFP. Recently, Ashton, Lee, Goldberg, and de Vries (2009) suggested that it is low er -order v ariables representing same-sign blends of multiple higher-order orthogonal dimensions that account for the noted associations betw een these dimensions, rather than a broad general factor. I t is also possible that ―halo effects‖ or ―egoistic bias‖ contribute to w hat may be mistakenly described as a GFP (Anusic, Schimmack, Pinkus, & Lockw ood, in press). Through this study, w e hav e demonstrated that the HEXACO model is a v alid framew ork structure that behav es similarly to the Big Fiv e model w hen assessed in conjunction w ith the four humor styles. The Honesty-Humility f actor of the HEXACO is Behavioral Genetic Study 27 also a justifiable addition to personality structure giv en its correlations w ith humor styles, and its etiologic al similarities to the other higher-order dimensions. 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About The Authors: Liv ia Veselka is a PhD student in the Department of Psychology at the Univ ersity of Western Ontario. Her research interests lie in the fields of behav ioral genetics and personality theory. Her prev ious public ations and conference presentations hav e largely addressed the theoretical structure of personality by examining existing models of personality, trait emotional intelligence, and the Dark Triad personality traits. Address for correspondence: Liv ia Veselka, Departme nt of Psychology, Westminster Hall, Univ ersity of Western Ontario, London, Ontario, Canada N6A 3K7 E-mail: lv eselka@uw o.ca Julie Aitken Schermer received her PhD in 1999. She was appointed assistant professor at Brescia University College from 2001-2003 and then assistant professor in the Management and Organizational Studies Program at The University of Western Ontario in 2003. She w as promoted to her current rank of associate professor in 2006. Her research mailto:lveselka@uwo.ca Behavioral Genetic Study 33 areas involve all aspects of human personality, intelligence, abilities, and interests. She has published 50 articles, one textbook, and has been involved in 67 conference presentations. Rod A. Martin completed his PhD in clinic al psychology at the Univ ersity of Waterloo in 1984, and has been a faculty member in the Department of Psychology at the Univ ersity of Western Ontario since then. His research focuses on the conceptualization and measurement of sense of humor, and on the association betw een humor and psychosocial w ell-being. He has serv ed as president of the I nternational Society of Humor Studies, is on the editorial board of Humor: International Journal of Humor Research , and is the author of the book The Psyc hology of Humor: An Integrative Approach. Lynn Cherkas is a research fellow at the Department of Tw in Research and Genetic Epidemiology (DTR), King’s College London, where she is head of the Behaviour Research Unit. Her main interest is in quantitative genetic analysis of twin data to assess the genetic and environmental influences on common complex diseases of aging and behav ioral traits. Lynn has published in leading scientific journals and liaises with the media to disseminate research findings. She has a BSc in psychology from the University of Birmingham and a D.Phil. in behav iour genetics from the University of Oxford. Tim D. Spector is a professor of genetic epidemiology at Kings College, London, and director of the Tw ins UK Registry at St Thomas’ Hospital, London. He founded the UK Tw ins Registry of 11,000 tw ins in 1993, w hich is one of the largest collections of genotype and phenotype information on twins worldwide. I ts breadth of research has expanded to cover a wide range of common complex traits, many of which were previously thought to be mainly due to ageing and environment. He has published over 450 research articles on common diseases and traits. Philip A. Vernon receiv ed his PhD in 1981 and w as appointed assistant professor in the Department of Psychology at the Univ ersity of Western Ontario in London, Ontario, Canada in 1982. He w as promoted to associate professor in 1987 and to full professor in 1992: a position he still holds. Vernon's research interests include indiv idual differences - broadly defined - and he has published ov er 125 articles, 30 book chapters, and 3 edited bookson suc h topics as intelligence and mental abilities, nor mal and abnor mal personality, and behav ioral genetics. Vernon has serv ed as President of the I nternational Society for the Study of I ndiv idual Di fferences and is co-editor in chief of Personality and I ndiv idual Differences. He also serv es on the board and as a rev iew er for numerous other journals.