Oddity, Schizotypy/Dissociation, and Personality

Transcription

1 Oddity, Schizotypy/Dissociation, and Personality Michael C. Ashton 1 and Kibeom Lee 2 1 Brock University 2 University of Calgary ABSTRACT The construct of Oddity was examined in relation to the dimensions of normal personality variation and a dimension of schizotypy and dissociation. In 2 studies involving samples of community adults (N = 409) and college students (N = 378), Oddity as operationalized in terms of perceived strangeness or eccentricity was found to be moderately related to a Schizotypy/Dissociation factor and also to factors of normal personality variation, particularly Openness to Experience. The modest loading of Oddity on the Schizotypy/Dissociation factor, along with the somewhat stronger projection of Oddity within the space of normal personality dimensions, indicates that the Schizotypy/ Dissociation factor should not be interpreted as a dimension of Oddity. The interpretation of the Schizotypy/Dissociation factor is discussed, as are the implications of these results for proposed dimensional models of personality disorders. In a recent article, Watson, Clark, and Chmielewski (2008) reported a series of factor analyses of self-report personality scales, including markers of the Big Five personality factors as well as several variables assessing dissociative or schizotypal characteristics. These analyses yielded six factors, five of which corresponded closely to the Big Five, with the remaining factor being defined by the dissociative and schizotypal scales. Watson et al. (2008) interpreted the factor defined by schizotypy and dissociation variables as Oddity, with reference to the odd or This research was supported by Social Sciences and Humanities Research Council of Canada grants and We thank Lewis R. Goldberg for making available the data from the Eugene- Springfield (Oregon) Community Sample. Correspondence concerning this article should be addressed to Michael C. Ashton, Department of Psychology, Brock University, St. Catharines, ON L2S 3A1 Canada. mashton@brocku.ca. Journal of Personality 80:1, February The Authors Journal of Personality 2012, Wiley Periodicals, Inc. DOI: /j x

2 114 Ashton & Lee eccentric cluster of personality disorders in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV; American Psychiatric Association, 1994). Among the diagnostic criteria for the disorders within this cluster are schizotypal features, which are strongly associated with dissociative tendencies (e.g., Watson, 2001). 1 But the interpretation of the factor defined by schizotypal and dissociative variables as Oddity was also meant to reflect the fact that schizotypy and dissociation are consensually perceived by observers as odd, eccentric, and peculiar. Watson et al. (2008) noted that such a factor had not been recovered in lexical studies of personality structure, and suggested that the absence of this factor was attributable in part to the decision by early lexical researchers to exclude terms such as odd, eccentric, and peculiar from their lists of personality traits. That is, Watson et al. implied that a personality-descriptive factor defined by terms denoting oddness, eccentricity, and peculiarity would correspond to the factor defined by scales assessing schizotypy and dissociation. The findings of Watson et al. (2008) have influenced the reconceptualization of personality pathology that has been proposed for the forthcoming fifth edition of the DSM (DSM-V). One aspect of this proposed reformulation is the inclusion of a dimensional model of personality disorder, and this model includes a dimension defined by schizotypy, dissociation, and various aspects of perceived oddity or eccentricity. The findings of Watson et al. (2008) are cited as the basis for the inclusion of this dimension (Clark & Krueger, 2010). However, the findings of Watson et al. (2008) raise two important questions. First, is the Schizotypy/Dissociation factor properly interpreted as a personality dimension of Oddity, in the sense of common personality characteristics such as odd, eccentric, peculiar, and the like? Second, if the Schizotypy/Dissociation factor is not interpretable as Oddity, then how should that factor be interpreted, and is this interpretation consistent with the inclusion of this factor within a dimensional model of personality disorder? With regard to the first question, it is plausible that the Schizotypy/Dissociation factor is interpretable as a personality 1. Watson (2001) found that schizotypal and dissociative tendencies formed two separate but very highly correlated factors. Even when the separation between these factors was maximized by removing items involving detachment or depersonalization from the scales measuring dissociation, the resulting dissociative factor correlated about.75 with the schizotypal factor.

3 Oddity 115 dimension of Oddity, for the simple reason that schizotypal and dissociative tendencies are perceived by most people as extremely odd or strange. However, it is also plausible that perceived oddity would be only modestly associated with schizotypy and dissociation, and that it would be more strongly associated with dimensions of normal personality variation. Even if perceived strangeness or eccentricity are attributable in part to schizotypal or dissociative tendencies, dimensions of normal personality variation would likely also be implicated: consider, for example, the nonconformity and creativity that define the Openness to Experience factor. Some previous research has already examined Oddity in relation to dimensions of normal personality variation or to markers of schizotypy and dissociation. Simms, Yufik, Thomas, and Nus Simms (2008) developed an Oddity scale whose items are statements about the extent to which one (or one s behavior or ideas) are odd, strange, weird, unusual, eccentric, or bizarre as opposed to ordinary, normal, or average. They reported that the Oddity scale correlated modestly with brief measures of Big Five Openness (.28), Conscientiousness (.34), and Agreeableness (.28); relations with markers of schizotypy and dissociation were not reported in that study. In an earlier study, Simms (2007) reported that an Unconventionality scale (Benet & Waller, 1995; based on that of Tellegen, Grove, & Waller, 1991) correlated only.18 with an Eccentric Perceptions scale (Clark, Simms, Wu, & Casillas, in press), which was a strong marker of the schizotypy/ dissociation-based factor obtained by Watson et al. (2008). In the same study, the Unconventionality scale correlated.29 and.24 with brief measures of Conscientiousness and Openness to Experience, respectively. Thus, the findings reported thus far suggest that Oddity is related to the dimensions of normal personality variation as well as the dimension of schizotypy and dissociation. In the present report, we examine the location of odd or eccentric traits within the space defined jointly by Schizotypy/Dissociation and the dimensions of normal personality variation. In our first study, we reanalyze a data set used by Watson et al. (2008, Study 3), examining the same markers of Schizotypy/Dissociation used in that report along with a measure of Oddity and with markers of the personality dimensions of the Big Five and HEXACO frameworks. In our second study, we collect data from a new sample of participants who completed measures of schizotypy/dissociation as well as the HEXACO factors and the Oddity scale of Simms et al. (2008).

4 116 Ashton & Lee We hypothesize that Oddity in the sense of a personality trait of perceived strangeness or eccentricity will load modestly on a dimension of schizotypy and dissociation, but will be at least as strongly influenced by the dimensions of normal personality, particularly Openness to Experience. To the extent that measures of oddity do not load strongly and univocally on the Schizotypy/ Dissociation factor, this would suggest that Schizotypy/Dissociation should not be interpreted as a dimension of Oddity (cf. Watson et al., 2008). Such a result would also suggest that the meaning of the Schizotypy/Dissociation factor and its status as a dimension of personality variation should be considered further. STUDY 1 Participants and Procedure Method Data collected from a total of 409 members of the Eugene-Springfield (Oregon) Community Sample (e.g., Goldberg, 1999a) were used in this study. Of these participants, 59% were women, with ages ranging from 20 to 83 years (Mdn = 49) in As noted below, the measures of the present study were completed in a series of mailings between 1994 and Participants responded to the measures at home and returned them by mail to the Oregon Research Institute. Measures We examined the five markers of the self-report Schizotypy/Dissociation factor interpreted as Oddity by Watson et al. (2008): the Curious Experiences Survey (CES; Goldberg, 1999b); the Somatoform Dissociation Questionnaire (SDQ; Nijenhuis, Spinhoven, Van Dyck, Van der Hart, & Vanderlinden, 1997); the Creative Experiences Questionnaire (CEQ; Merckelbach, Horselenberg, & Muris, 2001); the Magical Ideation Scale (MIS; Eckblad & Chapman, 1983); and the Obsessive-Compulsive Inventory (OCI; Foa, Kozak, Salkovskis, Coles, & Amir, 1998). The CES was administered in 1997, the OCI in 1999, and the SDQ, CEQ, and MIS in Note that although obsessive-compulsive symptoms are not generally considered to be indicators of schizotypal or dissociative tendency, we include the OCI in these analyses for the sake of consistency with Watson et al. Some items of the OCI refer to schizotypal- or dissociativelike symptoms, such as considering certain numbers as good or bad and having unpleasant thoughts that occur against one s will.

5 Oddity 117 We constructed a self-report Oddity scale by selecting International Personality Item Pool (IPIP; e.g., Goldberg, 1999a) items according to their content, selecting items in which the target person is described using the terms odd, eccentric, strange, unusual, unconventional, conventional, or normal. We identified eight such items; however, we removed four of the items due to some redundancies of content. Specifically, we kept only one of the four items that referred to the respondent s preference that others would not perceive him or her as odd, and we kept only one item that referred to eccentricity. The final set of four items was as follows: Am considered to be kind of eccentric, Do things that others find strange, Have a conventional lifestyle (reverse-scored), and Like to be thought of as a normal kind of person (reverse-scored). These four items were administered to the participants during different data collection stages; specifically, one item was administered in 1994, one in 2001, and two in All items were administered using a 1 5 response scale. Scale scores, computed as the mean across the four items, showed a mean of 2.21 (SD = 0.78). Internal-consistency reliability (alpha) was.71, and all items showed corrected item-total correlations of.45 or above. In our first analysis, we examined the Oddity and Schizotypy/ Dissociation variables along with self-reports on the 30 facet-level scales of the 240-item NEO Personality Inventory Revised (NEO-PI-R; Costa & McCrae, 1992), which was administered in All items were administered using a 5-point response scale. (For this analysis, 396 of the 409 participants had complete data.) In our second analysis, we examined the Oddity and Schizotypy/ Dissociation variables along with self-reports on the 24 facet-level scales of the 192-item version of the self-report HEXACO Personality Inventory (HEXACO-PI; Lee & Ashton, 2004), which was administered in All items were administered using a 5-point response scale. Factor Analyses Results and Discussion In our first analysis, we extracted six common factors (using the method of principal axes) from the set of 30 NEO-PI-R scales and five markers of Schizotypy/Dissociation. We then rotated the six factors to a varimax solution. Table 1 shows the loadings of the 35 variables on these factors. In our second analysis, we extracted seven common factors (using the method of principal axes) from the set of 24 HEXACO-PI scales and five markers of Schizotypy/Dissociation. We then rotated the

6 118 Ashton & Lee Table 1 Study 1: Extension Loadings of the IPIP Oddity Scale on Factors of Normal and Abnormal Personality (NEO-PI-R Variable Set) Factor Loadings of Core Variables C O A N EX S/D CES SDQ MIS CEQ OCI Anxiety Angry hostility Depression Self-consciousness Impulsiveness Vulnerability Warmth Gregariousness Assertiveness Activity Excitement seeking Positive emotions Fantasy Aesthetics Feelings Actions Ideas Values Trust Straightforwardness Altruism Compliance Modesty Tender-mindedness Competence Order Dutifulness Achievement striving Self-discipline Deliberation Factor Loadings of Extension Variable Oddity Note. N = 396; IPIP = International Personality Item Pool; C = Conscientiousness; O = Openness to Experience; A = Agreeableness; N = Neuroticism; EX = Extraversion; S/D = Schizotypy/Dissociation; CES = Curious Experiences Survey; SDQ = Somatform Dissociation Questionnaire; MIS = Magical Ideation Scale; CEQ = Creative Experiences Questionnaire; OCI = Obsessive-Compulsive Inventory. All variables without a prefix are facet-level scales of the NEO Personality Inventory Revised. Loadings with absolute values of.40 or above are given in boldface type.

7 Oddity 119 seven factors to a varimax solution. Table 2 shows the loadings of the 29 variables on these factors. Schizotypy/Dissociation as a Separate Factor? One might wonder whether the emergence of Schizotypy/ Dissociation as a separate factor in the above analyses was due simply to the inclusion of several strongly intercorrelated marker variables. We examined this possibility in two ways. First, we conducted additional factor analyses in which we included only two conceptually distinct markers of Schizotypy/Dissociation (specifically, magical ideation and somatoform dissociation) along with the NEO-PI-R and HEXACO-PI scales, respectively. The six-factor solution (NEO-PI-R) and the seven-factor solution (HEXACO-PI) again identified a Schizotypy/Dissociation dimension that was defined strongly (and solely) by these two scales. Second, we conducted additional factor analyses using an oblique rotation (promax, with kappa = 4) to find out how strongly the original Schizotypy/ Dissociation factor would be correlated with the five NEO-PI-R or the six HEXACO-PI factors. In both cases, the correlations involving Schizotypy/Dissociation were modest and were exceeded by at least some of the remaining intercorrelations: in the NEO-PI-R solution, Schizotypy/Dissociation correlated.40 with Neuroticism (and had no other absolute correlations reaching.25), whereas Extraversion and Openness to Experience correlated.49. In the HEXACO-PI solution, Schizotypy/Dissociation correlated.34 with Honesty- Humility (and had no other absolute correlations reaching.25), whereas Honesty-Humility and Agreeableness correlated.42. Taken together, these results indicate that the Schizotypy/Dissociation factor was not a bloated specific but instead fell largely outside the space of the NEO-PI-R and HEXACO-PI variable sets. Minimum Average Partial and Parallel Tests Our decision to extract six factors (in the NEO-PI-R analysis) and seven factors (in the HEXACO-PI analysis) was based on the consistent previous findings of five NEO-PI-R and six HEXACO-PI factors, along with the expectation of a separate Schizotypy/ Dissociation factor, as supported by the analyses noted above. In a more exploratory study, one could decide on the number of factors to extract by using such methods as the minimum average partial and

8 120 Ashton & Lee Table 2 Study 1: Extension Loadings of the IPIP Oddity Scale on Factors of Normal and Abnormal Personality (HEXACO-PI Variable Set) Factor Loadings of Core Variables S/D O A E C H X CES SDQ MIS CEQ OCI Sincerity Fairness Greed avoidance Modesty Fearfulness Anxiety Dependence Sentimentality Expressiveness Social boldness Sociability Liveliness Forgiveness Gentleness Flexibility Patience Organization Diligence Perfectionism Prudence Aesthetic appreciation Inquisitiveness Creativity Unconventionality Factor Loadings of Extension Variable Oddity Note. N = 409; IPIP = International Personality Item Pool S/D = Schizotypy/Dissociation; O = Openness to Experience; A = Agreeableness; E = Emotionality; C = Conscientiousness; H = Honesty-Humility; X = Extraversion; CES = Curious Experiences Survey; SDQ = Somatoform Dissociation Questionnaire; MIS = Magical Ideation Scale; CEQ = Creative Experiences Questionnaire; OCI = Obsessive-Compulsive Inventory. All variables without a prefix are facet-level scales of the HEXACO Personality Inventory. Loadings with absolute values of.40 or above are given in boldface type.

9 Oddity 121 parallel tests. (We thank an anonymous reviewer for recommending these analyses in the present report.) In the case of the variable set that included the NEO-PI-R plus Schizotypy/Dissociation, the minimum average partial test suggested a six-factor solution, as the smallest mean squared partial correlation was found for that solution (.0140), with larger values observed for five- and seven-factor solutions (.0170 and.0146, respectively). Likewise, the parallel test also suggested a six-factor solution in that variable set, as the observed eigenvalues (6.96, 4.52, 3.44, 2.65, 1.95, 1.73, 1.07, 0.99, 0.87,...) exceeded the 95th percentile eigenvalues obtained from 1,000 random data sets (1.68, 1.59, 1.52, 1.46, 1.42, 1.37, 1.33, 1.30,...) for the first six factors. In the case of the variable set that included the HEXACO-PI plus Schizotypy/Dissociation, the minimum average partial test suggested a seven-factor solution, as the smallest mean squared partial correlation was found for that solution (.0167), with larger values observed for six- and eight-factor solutions (.0186 and.0185, respectively). Likewise, the parallel test also suggested a seven-factor solution in that variable set, as the observed eigenvalues (4.23, 3.80, 2.96, 2.37, 2.15, 1.75, 1.33, 0.84, 0.75,...) exceeded the 95th percentile eigenvalues obtained from 1,000 random data sets (1.61, 1.51, 1.44, 1.39, 1.35, 1.30, 1.26, 1.22, 1.19,...) for the first seven factors. Extension Loadings of Oddity To examine the location of the IPIP Oddity scale within the factor spaces of the two solutions described above, we conducted an extension analysis using the program of O Connor (2001). In extension analysis (e.g., Gorsuch, 1997), a set of core variables is factor analyzed, and then the loadings of one or more extension variables are computed within the space defined by the core variables. The advantage of extension analysis, in contrast to a joint factor analysis of the core and extension variables, is that the extension variable(s) do not influence the factor space. That is, by using extension analysis to examine the location of IPIP Oddity, we avoided the problem that this variable would itself influence the factor axis locations. Extension loadings of Oddity on the factors of the two solutions are shown in Tables 1 and 2. As seen in both Table 1 and Table 2, the IPIP Oddity scale did show an appreciable positive loading on the Schizotypy/Dissociation

10 122 Ashton & Lee factor (.21 in the NEO-PI-R analysis and.32 in the HEXACO-PI analysis). However, IPIP Oddity also showed stronger loadings on the Openness to Experience factor (.41 in the NEO-PI- R analysis and.43 in the HEXACO-PI analysis). These results indicate that the trait of Oddity is influenced in part by Schizotypy/Dissociation but that it is influenced more strongly by normal personality dimensions, particularly Openness to Experience. 2 STUDY 2 In Study 2, we again investigated the relations of perceived oddity or eccentricity with the seven-factor space defined by the six HEXACO dimensions plus the Schizotypy/Dissociation factor. In this study, we examined these relations in a sample of college students, and we modified several features of the variable set. First, we used a revised and shorter measure of the HEXACO personality factors. In addition, we assessed the Schizotypy/ Dissociation factor using the three subscales of one of the scales included in Study 1, specifically, Goldberg s CES. We assessed Oddity using the scale developed by Simms et al. (2008), and we examined both self-reports and observer reports on that scale; in this way, we could examine the question of whether Oddity as perceived by other persons would be located in the same region of the personality space as would self-perceived Oddity. Participants and Procedure A total of 378 undergraduate students (56% women, median age 20 years) participated in this study in return for course credit or money. Advertisements solicited participation by pairs of well-acquainted persons (romantic partners, siblings, and friends) who had known each other well for at least 6 months. Pairs of participants attended data collection sessions in small groups; participants of the same pair were separated during the sessions to prevent communication between them. Each participant provided self-reports on a variety of measures and also provided observer reports on a subset of those measures for the other member of his or her pair. 2. The full matrices of correlations among variables are available from the authors. Correlations among the broad domain-level variables are shown in Appendices A and B.

11 Oddity 123 Measures We administered Goldberg s (1999b) Curious Experiences Survey (CES), and we used the three subscales (Depersonalization/ Derealization, Absorption, and Amnesia) as markers of a Schizotypy/Dissociation factor. (Note that although the CES subscales do not directly assess schizotypal constructs, the CES Depersonalization/Derealization subscale assesses the detachment that Watson [2001] found to be nearly perfectly correlated with a schizotypy factor.) We administered the 100-item version of the HEXACO Personality Inventory Revised (HEXACO-PI-R; e.g., Lee et al., 2009). The HEXACO-PI-R contains four facet-level scales for each of the six factors, plus an interstitial scale (Altruism vs. Antagonism) that we did not include in the analyses of this report. Note that within the Extraversion factor scale, the HEXACO-PI Expressiveness facet scale is replaced in the HEXACO-PI-R by the Social Self-Esteem facet scale. All items were administered using a 5-point response scale. We also administered the Evaluative Person Descriptors Questionnaire (EPDQ; Simms et al., 2008), using the standard 1 5 response scale. For the purpose of the present study, we focus only on the Oddity scale, and we consider both self-reports and observer reports on that scale. (In converting the self-report Oddity scale to an observer report scale, we used traditional informant wording as described by Simms, Zelazny, Yam, & Gros, 2010.) Scale scores, computed as item means across the 12 items, showed a mean of 2.79 (SD = 0.76) in self-reports and a mean of 2.53 (SD = 0.78) in observer reports. Internal-consistency reliabilities (alpha) were.91 in self-reports and.92 in observer reports. The correlation between self- and observer reports of Oddity was.34, which falls within the range of self/observer correlations reported previously for this scale (cf. r =.44 in Simms et al., 2008; r =.28 in Simms et al., 2010). Factor Analysis Results and Discussion We extracted seven common factors (using the method of principal axes) from the set of 24 HEXACO-PI scales and three CES subscales. We then rotated the seven factors to a varimax solution. Table 3 shows the loadings of the 27 variables on these factors.

12 124 Ashton & Lee Table 3 Study 2: Extension Loadings of the EPDQ Oddity Scale on Factors of Normal and Abnormal Personality Factor Loadings of Core Variables X E A O C S/D H CES Depersonalization CES Absorption CES Amnesia Sincerity Fairness Greed avoidance Modesty Fearfulness Anxiety Dependence Sentimentality Social self-esteem Social boldness Sociability Liveliness Forgiveness Gentleness Flexibility Patience Organization Diligence Perfectionism Prudence Aesthetic appreciation Inquisitiveness Creativity Unconventionality Factor Loadings of Extension Variables EPDQ Oddity-Self EPDQ Oddity-Peer Note. N = 378. EPDQ = Evaluative Person Descriptors Questionnaire; X = Extraversion; E = Emotionality; A = Agreeableness; O = Openness to Experience; C = Conscientiousness; S/D = Schizotypy/Dissociation; H = Honesty-Humility; CES = Curious Experiences Survey. All variables without a prefix are facet-level scales of the HEXACO Personality Inventory Revised. Loadings with absolute values of.40 or above are given in boldface type.

13 Oddity 125 As in the Study 1 analyses involving the HEXACO-PI variable set, our decision to extract seven factors was based on the consistent previous findings of six HEXACO-PI factors, along with the expectation of a separate Schizotypy/Dissociation factor. Again, in a more exploratory study, one could decide on the number of factors to extract by using such methods as the minimum average partial and parallel tests. (We thank an anonymous reviewer for recommending these analyses in the present report.) In the variable set of this study, the minimum average partial test actually suggested a six-factor solution, as the smallest mean squared partial correlation was found for that solution (.0172), with larger values observed for five- and seven-factor solutions (.0184 and.0180, respectively). Likewise, the parallel test also suggested a six-factor solution in this variable set, as the observed eigenvalues (3.59, 3.02, 2.80, 2.34, 1.86, 1.53, 1.19, 0.92, 0.82,...) exceeded the 95th percentile eigenvalues obtained from 1,000 random data sets (1.60, 1.50, 1.44, 1.38, 1.33, 1.28, 1.25, 1.21, 1.17,...) for the first six factors. 3 When we examined the six-factor solution, we found that the Schizotypy/ Dissociation variables continued to define a separate factor. However, the Honesty-Humility facet scales no longer defined their own factor, and instead showed modest loadings (all below.45) on the Agreeableness factor. Extension Loadings of Oddity To examine the location of the EPDQ Oddity scale within this sevenfactor space, we again conducted an extension analysis using the program of O Connor (2001), as explained in Study 1 of this report. Extension loadings of both self-report and observer report EPDQ Oddity on the seven factors are shown in Table We suggest that the minimum average partial results reflect a tendency for this technique to underestimate slightly the number of factors, particularly when factors are defined by few variables and when loadings are not extremely high (see Zwick & Velicer, 1986, p. 440). Also, we suggest that the parallel analysis results reflect the modest sample size of this study; in larger samples based on the HEXACO-PI-R variable set alone (i.e., without markers of a Schizotypy/ Dissociation factor), the parallel test generally indicates six factors, and the same six factors consistently emerge from that variable set. 4. The full matrix of correlations among variables is available from the authors. Correlations among the broad domain-level variables are shown in Appendix C.

14 126 Ashton & Lee As seen in Table 3, the self-report EPDQ Oddity scale loaded modestly on the Schizotypy/Dissociation factor (.26), but also loaded more strongly on Openness to Experience (.42). Results for the peer report EPDQ Oddity scale (also given in Table 3) show a similar pattern but with weaker loadings:.17 for Schizotypy/ Dissociation and.22 for Openness to Experience. (The weaker loadings for observer report Oddity, relative to self-report Oddity, are likely due to the fact that the personality variables were assessed via self-report. Recall that self- and observer reports of Oddity correlated.34 in this sample.) As in Study 1, the results of Study 2 indicate that the trait of Oddity is influenced in part by the Schizotypy/Dissociation factor, but that it is influenced more strongly by normal personality dimensions, particularly Openness to Experience. GENERAL DISCUSSION The results of this investigation suggest that the factor defined by markers of schizotypy and dissociation should not be interpreted as a dimension of Oddity. Our results indicated that measures of perceived oddity or eccentricity were not univocally or even primarily associated with the dimension of schizotypal and dissociative tendency. In both of our studies, oddity markers instead showed a considerably stronger projection within the plane of normal personality variation mainly on the Openness to Experience axis than on the dimension of Schizotypy/Dissociation. That is, oddity variables were found to represent mainly a blend of high Openness to Experience and other personality dimensions, with some modest additional influence of the Schizotypy/Dissociation factor. Although each of our studies had its limitations specifically, the use of an ad hoc Oddity scale in Study 1 and the somewhat narrow array of Schizotypy/Dissociation markers in Study 2 the results were entirely consistent across those two studies. The present results allow us to rule out one potential explanation for the nonemergence of a schizotypal or dissociative factor in lexical studies of personality structure. Watson et al. (2008) suggested that the exclusion from lexical investigations of terms such as odd, eccentric, and peculiar had precluded the identification of the factor that in their research was defined by scales assessing

15 Oddity 127 schizotypy and dissociation. (Recall that this factor was called Oddity by Watson et al. but was not chiefly defined by scales assessing perceived peculiarity or eccentricity.) However, the findings of this report indicate that oddity-related terms are not strong markers of a Schizotypy/Dissociation factor, which suggests that the absence of this factor in lexical studies of personality structure is not due to any exclusion of those terms. Instead, the nonemergence of such a factor more likely reflects the fact that there are relatively few adjectives that chiefly describe persons having schizotypal and dissociative tendencies. We suggest two reasons for the limited representation of terms describing schizotypy and dissociation in natural languages. First, the more benign expressions of this dimension, although rather common, are also rather unimportant in person description. As noted by Watson et al. (2008, p. 1576), the defining characteristics of this factor are less relevant to an understanding of basic, normalrange personality functioning. Moreover, the few terms that might be considered as descriptors of schizotypal or dissociative tendencies (e.g., forgetful, dreamy, superstitious) are likely also influenced by other personality factors. Second, the more pathological expressions are probably so rare and so striking that people have little need to use a wide array of subtly different terms to describe those manifestations of schizotypy and dissociation, and instead rely on a few crude synonyms (e.g., crazy, insane). We should note that the results of this study differ somewhat from those reported in Study 2 of Watson et al. (2008). Among the variables analyzed in that study was the Odd or Eccentric Behavior scale of the Schizotypal Personality Questionnaire (SPQ; Raine, 1991). That scale, whose items describe perceived oddness and eccentricity, showed promax-rotated factor loadings of.42 on a Schizotypy/ Dissociation factor and only.20 on an Openness to Experience factor. We suspect that the relatively low loading on the Openness factor in that study is partly due to the relatively narrow content of that factor, which was defined by two brief, global marker scales rather than by several distinct facets. Also, we suspect that the somewhat higher loading on the factor of schizotypy and dissociation is largely due to the common item format across all SPQ scales (i.e., yes/no responses with no reverse-keyed items), which would tend to inflate correlations among all of those scales. In any case, the loading of SPQ Odd or Eccentric Behavior on the Schizotypy/Dissociation

16 128 Ashton & Lee factor of that study was not nearly high enough to suggest that perceived oddity or eccentricity represents the central feature of the factor. (Note that two other SPQ scales also have the term odd in their names, but their content does not correspond so closely to perceived oddity or eccentricity. The Odd Speech scale mainly contains items that describe a confused or incoherent style of speaking, and the Odd Beliefs scale contains items that describe subjective experiences of magical or supernatural phenomena.) Given that the factor defined by schizotypy and dissociation cannot be interpreted as a dimension of Oddity, the question arises as to whether this factor can be said to represent a dimension of personality variation at all. We suggest that there are reasons to classify the Schizotypy/Dissociation factor as a dimension of individual differences that falls outside the personality domain. Consider that the common element of the variables that define the Schizotypy/Dissociation factor most strongly and univocally involves distorted perceptions of reality, particularly in the relations between oneself and one s surroundings. These distorted perceptions include body-image aberrations (e.g., feeling disconnected from one s body), magical perceptions (e.g., sensing that one is receiving telepathic communications), confusion of fantasy with reality (e.g., feeling uncertain whether an event actually happened or whether one merely imagined it), auditory or visual hallucinations (e.g., hearing voices or seeing figures that do not exist), and ideas of reference (e.g., perceiving publicly broadcast information as being specifically meant for oneself). That is, the Schizotypy/Dissociation factor represents individual differences in the frequency or intensity of these perceptual distortions. In contrast, none of the major dimensions of personality variation represents any such contrast between the absence or presence of some perceptual distortion; instead, each of the major personality factors represents a contrast between two opposing styles of typical behavioral tendency (see factor-by-factor discussions in Ashton & Lee, 2007). Moreover, many persons experience virtually no perceptual distortions at all, and hence show a true zero level of the Schizotypy/Ddissociation dimension. In contrast, each of the major dimensions of personality is characterized by continuous variation toward both the high and low poles, with no apparent zero threshold. In these senses, the Schizotypy/Dissociation factor is qualitatively distinct from the major factors of personality variation.

17 Oddity 129 This is not to say that the Schizotypy/Dissociation factor does not contribute to variation in characteristics that do represent personality traits. On the contrary, many traits appear to be influenced jointly by Schizotypy/Dissociation and by one or more personality dimensions. We have shown in this article that perceived oddity or eccentricity represents a blend of high Openness to Experience and other personality factors (e.g., low Conscientiousness), along with a significant element of Schizotypy/Dissociation. Some other personality traits, such as openness to fantasy or imaginative absorption, are likely to represent roughly similar blends of underlying factors. Beyond the domain of personality characteristics proper, individuals beliefs regarding the possible existence of paranormal phenomena are also likely to be influenced jointly by Schizotypy/ Dissociation and Openness, with the perceptual experiences of the former dimension adding to the open-minded theoretical orientation of the latter. A noteworthy finding of this report is that measures of Schizotypy/Dissociation were nearly uncorrelated with measures of Openness to Experience (see correlations in Appendices A, B, and C). We interpret this result as indicating simply that the underlying constructs of Schizotypy/Dissociation and Openness to Experience are in fact independent of one another. An alternative possibility is that either or both of these constructs were not properly operationalized by the measures used in this study, and that more appropriate measures would have shown substantial intercorrelations. For example, with regard to the measures of Schizotypy/ Dissociation used in this study, one might suggest that correlations with Openness to Experience would have been higher if the measures of the dissociative aspects of the former construct had been replaced with additional measures of the schizotypal aspects. We believe that this is likely to be the case, insofar as some secondary element of Openness to Experience is likely to be implicated in certain characteristics that are considered as manifestations of schizotypy (e.g., as noted above, fantasy proneness and paranormal beliefs). Nevertheless, the findings of this study suggest that the large common element shared by diverse measures of schizotypy and dissociation is independent of Openness to Experience as measured by this study. Likewise, with regard to the measures of Openness to Experience used in this study, one might suggest that correlations with

18 130 Ashton & Lee Schizotypy/Dissociation would have been higher if the former construct had been conceptualized and operationalized differently. For example, Haigler and Widiger (2001) found that the items of NEO-PI-R Openness to Experience generally assessed adaptive, but not maladaptive, variants of this dimension of personality. Those authors rephrased the items so that these described excessive levels of Openness to Experience and found that the rephrased Openness to Experience scale showed modest positive correlations (in the.20s and.30s) with measures of schizotypal personality disorder, whereas the original Openness to Experience scale showed statistically nonsignificant negative correlations with those measures. The present study did not include any such rephrased Openness to Experience scales; however, the Oddity scales might themselves be considered to represent maladaptive or poorly socialized variants of Openness to Experience, and these scales did show some modest associations with Schizotypy/Dissociation. Thus, it is possible that if the Openness to Experience factor were conceptualized and operationalized somewhat differently, it would show some modest associations with some measures of Schizotypy/ Dissociation. Finally, we should discuss the implications of this investigation for the inclusion of a Schizotypy dimension within the model of personality disorder characteristics that has been proposed for the DSM-V (see Clark & Krueger, 2010). The proposed Schizotypy dimension is conceptualized as being defined by five facets that appear to span the three-dimensional space that is defined by the Schizotypy/Dissociation dimension and by the personality dimensions of Openness to Experience and Conscientiousness. One of the proposed facets, Dissociation, seems to represent the Schizotypy/ Dissociation factor almost univocally. In contrast, the proposed Eccentricity facet is rather similar to the Oddity variables examined in the present study, although with some specifically speechrelated aspects that may have a stronger element of Schizotypy/ Dissociation. The other three proposed facets, named Unusual Perceptions, Unusual Beliefs, and Cognitive Dysregulation, appear to represent blends of Schizotypy/Dissociation with Openness to Experience or (in the latter case) low Conscientiousness. Note that, because these five facets are all likely to be influenced by the same set of underlying dimensions, they are likely to be mutually intercorrelated and hence to define a common factor. However, that common

19 Oddity 131 factor would itself represent a compound of the orthogonal dimensions that jointly influence its defining facets. 5 We suggest that the reformulation of personality disorders in the DSM-V would be better served by a dimensional model in which each dimension is an independent major factor of personality variation, rather than a compound of two or more personality factors and/or the Schizotypy/Dissociation factor. In order to provide a complete description of personality variation, this would necessitate the addition of a separate Openness to Experience factor, which is not directly represented among the proposed DSM-V dimensions. Also, given that the Schizotypy/Dissociation factor is qualitatively different from the major dimensions of personality variation, we suggest that its inclusion within the dimensional model of personality should be carefully considered. On the one hand, these qualitative differences suggest that Schizotypy/Dissociation should be classified within a different category of individual differences. On the other hand, the structure of the DSM may make it difficult to find an appropriate home for a dimension that subsumes both schizotypal and dissociative tendencies (see Watson et al., 2008), and clinicians may well prefer to maintain continuity between the DSM-V and its predecessors. 5. A similar point can be raised regarding the proposed Antagonism factor (Clark & Krueger, 2010), as the proposed facets of this factor represent varying (and highly unpleasant) blends of two factors, low Honesty-Humility and low Agreeableness (vs. Anger). Conversely, however, the proposed Disinhibition and Compulsivity factors would mainly appear to represent opposite poles of the Conscientiousness factor, and hence might be replaced by a single bipolar dimension.

20 132 Ashton & Lee REFERENCES American Psychiatric Association. (1994). Diagnostic and statistical manual of mental disorders. (4th ed.). Washington, DC: Author. Ashton, M. C., & Lee, K. (2007). Empirical, theoretical, and practical advantages of the HEXACO model of personality structure. Personality and Social Psychology Review, 11, Benet, V., & Waller, N. G. (1995). The Big Seven model of personality description: Evidence for its cross-cultural generality in a Spanish sample. Journal of Personality and Social Psychology, 69, Clark, L. A., & Krueger, R. F. (2010). Rationale for a six-domain trait dimensional diagnostic system for personality disorder. American Psychiatric Association. DomainTraitDimensionalDiagnosticSystemforPersonalityDisorder.aspx Clark, L. A., Simms, L. J., Wu, K. D., & Casillas, A. (in press). Schedule for Nonadaptive and Adaptive Personality Second Edition (SNAP-2). Manual for administration, scoring, and interpretation (2nd ed.). Minneapolis: University of Minnesota Press. Costa, P. T., Jr., & McCrae, R. R. (1992). Revised NEO Personality Inventory (NEO-PI-R) and NEO Five-Factor Inventory (NEO-FFI) Professional Manual. Odessa, FL: Psychological Assessment Resources. Eckblad, M., & Chapman, L. J. (1983). Magical ideation as an indicator of schizotypy. Journal of Consulting and Clinical Psychology, 51, Foa, E. B., Kozak, M. J., Salkovskis, P. M., Coles, M. E., & Amir, N. (1998). The validation of a new obsessive-compulsive disorder scale: The Obsessive- Compulsive Inventory. Psychological Assessment, 10, Goldberg, L. R. (1999a). A broad-bandwidth, public-domain, personality inventory measuring the lower-level facets of several five-factor models. In I. Mervielde, I. Deary, F. De Fruyt, & F. Ostendorf (Eds.), Personality psychology in Europe (Vol. 7, pp. 7 28). Tilburg, The Netherlands: Tilburg University Press. Goldberg, L. R. (1999b). The Curious Experiences Survey, a revised version of the Dissociative Experiences Scale: Factor structure, reliability, and relations to demographic and personality variables. Psychological Assessment, 11, Gorsuch, R. L. (1997). A new procedure for extension analysis in exploratory factor analysis. Educational and Psychological Measurement, 57, Haigler, E. G., & Widiger, T. A. (2001). Experimental manipulation of NEO-PI-R items. Journal of Personality Assessment, 77, Lee, K., & Ashton, M. C. (2004). The HEXACO Personality Inventory: A new measure of the major dimensions of personality. Multivariate Behavioral Research, 39, Lee, K., Ashton, M. C., Pozzebon, J. A., Visser, B. A., Bourdage, J. S., & Ogunfowora, B. (2009). Similarity and assumed similarity in personality reports of well-acquainted persons. Journal of Personality and Social Psychology, 96, Merckelbach, H., Horselenberg, R., & Muris, P. (2001). The Creative Experiences Questionnaire (CEQ): A brief self-report measure of fantasy proneness. Personality and Individual Differences, 31,

21 Oddity 133 Nijenhuis, E. R. S., Spinhoven, P., Van Dyck, R., Van der Hart, O., & Vanderlinden, J. (1997). The development of the Somatoform Dissociation Questionnaire (SDQ-5) as a screening instrument for dissociative disorders. Acta Psychiatrica Scandinavica, 96, O Connor, B. P. (2001). EXTENSION: SAS, SPSS, and MATLAB programs for extension analysis. Applied Psychological Measurement, 25, 88. Raine, A. (1991). The SPQ: A scale for the assessment of schizotypal personality based on DSM-III-R criteria. Schizophrenia Bulletin, 17, Simms, L. J. (2007). The Big Seven model of personality and its relevance to personality pathology. Journal of Personality, 75, Simms, L. J., Yufik, T., Thomas, J. P., & Nus Simms, E. (2008). Exploring the nature of evaluative person descriptors through scale development. Journal of Research in Personality, 42, Simms, L. J., Zelazny, K., Yam, W. H., & Gros, D. F. (2010). Self-informant agreement for personality and evaluative person descriptors: Comparing methods for creating informant measures. European Journal of Personality, 24, Tellegen, A., Grove, W. M., & Waller, N. G. (1991). Inventory of Personal Characteristics #7 (IPC7). Unpublished materials, Department of Psychology, University of Minnesota. Watson, D. (2001). Dissociations of the night: Individual differences in sleeprelated experiences and their relation to dissociation and schizotypy. Journal of Abnormal Psychology, 110, Watson, D., Clark, L. A., & Chmielewski, M. (2008). Structures of personality and their relevance to psychopathology: II. Further articulation of a comprehensive unified trait structure. Journal of Personality, 76, Zwick, W. R., & Velicer, W. F. (1986). Comparison of five rules for determining the number of components to retain. Psychological Bulletin, 99, Appendix A Study 1: Correlations Among Domain-Level Scales (NEO-PI-R Variable Set) a Mean SD Neuroticism Extraversion Openness to Experience 4. Agreeableness Conscientiousness Schizotypy/ Dissociation 7. Oddity Note. N = 396. Schizotypy/Dissociation scale is computed as the mean of standardized scores on the five markers of this factor. See Costa and McCrae (1992) for computation of NEO-PI-R scale scores.

22 134 Ashton & Lee Appendix B Study 1: Correlations Among Domain-Level Scales (HEXACO-PI Variable Set) a Mean SD Honesty-Humility Emotionality Extraversion Agreeableness Conscientiousness Openness to Experience Schizotypy/ Dissociation Oddity Note. N = 409. Schizotypy/Dissociation scale is computed as the mean of standardized scores on the five markers of this factor. Appendix C Study 2: Correlations Among Domain-Level Scales a Mean SD Honesty-Humility Emotionality Extraversion Agreeableness Conscientiousness Openness to Experience Schizotypy/ Dissociation Oddity-Self Oddity-Peer Note. N = 378.