Relationship between Cattell’s 16PF and fluid and crystallized intelligence

Personality and Individual Differences 51 (2011) 63–67 Contents lists available at ScienceDirect Personality and Individual Differences journal homepage: www.elsevier.com/locate/paid Relationship between Cattell’s 16PF and fluid and crystallized intelligence Nermin Djapo ⇑, Jadranka Kolenovic-Djapo, Ratko Djokic, Indira Fako Department of Psychology, Philosophical Faculty, University of Sarajevo, Franje Rackog 1, Sarajevo, Bosnia and Herzegovina a r t i c l e i n f o Article history: Received 3 December 2010 Received in revised form 3 March 2011 Accepted 9 March 2011 Available online 3 April 2011 Keywords: 16PF Fluid intelligence Crystallized intelligence a b s t r a c t The aim of the study was to explore the relationship between the five global factors and 16 dimensions of Cattell’s personality model and fluid and crystallized intelligence. A total of 105 third graders (45.7% males) of three high schools participated in the research. Fluid intelligence was measured by Raven’s Advanced Progressive Matrices and crystallized intelligence was measured by the Mill Hill Vocabulary Scale. Personality traits were measured by the Sixteen Personality Factor Questionnaire. Anxiety is correlated neither with fluid nor with crystallized intelligence. Extraversion and Self-Control are negatively correlated with fluid intelligence whereas Tough-Mindedness is positively correlated with it. Independence is positively correlated with crystallized intelligence and Tough-Mindedness is negatively correlated with it. Regression analysis reveals that all broad personality factors, except anxiety, are significant predictors of fluid intelligence. When combined together, these factors account for 25% of the variance of fluid intelligence scores. The regression model with crystallized intelligence as a criterion variable is not statistically significant. The study results are consistent with the Chamorro-Premuzic and Furnham’s (2005) two-level conceptual framework. Although using a different taxonomy of personality, the results are in accordance with the model’s presuppositions. Ó 2011 Elsevier Ltd. All rights reserved. 1. Introduction In the 1990s, interest in research on the relationship between intelligence and personality was revived, especially after more detailed analyses of the correlation as interpreted by Saklofske and Zeidner (1995) and Sternberg and Ruzgis (1994), Ackerman and Heggestad’s meta-analysis of the interconnectedness of personality constructs and intelligence (1997) and particularly after leading authors in individual differences psychology reached a consensus in regards to the organisation of intellectual abilities and personality structures. Chamorro-Premuzic and Furnham (2004), Chamorro-Premuzic and Furnham (2005) proposed a framework for interpreting the relationship between intelligence and personality traits. Their two-level conceptual framework is based on the Big-Five personality model and concepts of fluid and crystallized intelligence. This study is aimed at testing the basic assumptions of the Chamorro-Premuzic and Furnham conceptual framework with Cattell’s model of 16 personality factors as a foundation for the operationalisation of personality traits. The majority of theoreticians believe that intelligence is hierarchically organised with a general factor on top which can account for the individual differences in the subordinated factors (Carroll 1993; Gustafsson, 1988). One of the most influential theories of intelligence is Cattell’s theory of fluid and crystallized intelligence. ⇑ Corresponding author. Tel.: +387 33253125. E-mail address: nermin.djapo@ff.unsa.ba (N. Djapo). 0191-8869/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.paid.2011.03.014 Fluid intelligence refers to the processing of information and the ability to reason with the aim to understand relationships and abstract propositions (Stankov, 2000), whereas crystallized intelligence refers to the acquisition, storing, organisation and conceptualisation of pieces of information (Chamorro-Premuzic & Furnham, 2005). In the field of personality psychology, the Big-Five personality framework dominates the trait approach to personality. According to the Big Five model, personality traits can be organised within five broad and basic dimensions: Extraversion, Agreeableness, Conscientiousness, Emotional Stability, and Openness to Experience. These fundamental dimensions are personality dispositions that allow us to understand the consistency of an individual’s thinking, feeling and behavior, relatively independent of the situation, context and time (Chamorro-Premuzic & Furnham, 2005). In studies of the relationship between intelligence and personality traits the most frequent results are low to moderate coefficients of correlation between intelligence and the Big Five dimensions. The correlation between Openness to Experience and intelligence is moderate and positive (Ackerman & Heggestad, 1997; Austin et al., 2002; Chamorro-Premuzic, Moutafi, and Furnham, 2005). Furthermore, studies point to a low and negative correlation between Conscientiousness and intelligence (Ackerman & Heggestad, 1997; Austin et al., 2002; Moutafi, Furnham, & Crump, 2003) whereas the correlation between Neuroticism and intelligence is usually negative (Ackerman & Heggestad, 1997; Austin et al., 2002). The results of research on the correlation 64 N. Djapo et al. / Personality and Individual Differences 51 (2011) 63–67 between Extraversion and intelligence are inconsistent; in some studies the authors report a positive correlation (e.g. Ackerman & Heggestad, 1997), while other researchers report a zero correlation (e.g. Austin et al., 2002), and even a negative correlation (Austin et al., 2002). Of the Big Five personality traits, Agreeableness is the least correlated with intelligence. Ackerman and Heggestad (1997) determined positive, low and statistically insignificant coefficients of correlation between Agreeableness and intelligence. However, a meta-analytical study by Austin et al. (2002) found low, negative, statistically significant correlations. Chamorro-Premuzic and Furnham (2004), Chamorro-Premuzic and Furnham (2005) proposed a two-level conceptual framework for understanding the results found in investigations of the relationship between the five broad personality traits and fluid and crystallized intelligence. The first level of the model refers to the ability as test performance output (measured directly) and to the effects of Neuroticism and Extraversion on the results of intelligence testing. The negative effects (anxiety, worry, tension, depression, anger) interfere with the cognitive processes needed for an efficient solution of a problem (Chamorro-Premuzic & Furnham, 2005). On the other hand, the correlation between Extraversion and intelligence depends on the nature of the intelligence test (Chamorro-Premuzic & Furnham, 2005). Extraverted persons were more successful in time-limited tests, while the introverts were more successful in those tasks that were not time-limited and needed introspection. Eysenck and Eysenck (1985) explained such a correlation between Extraversion and intelligence by a theory of arousal. According to this theory introverts have a lower reactive inhibition due to which they display a tendency to avoid arousal stimuli, unlike extraverts who show a tendency towards the arousal stimulus. The second level of the model refers to the abilities as a capacity (i.e., they cannot be measured directly) and to the conceptualisation of the correlation between Conscientiousness and fluid intelligence on one side and Openness and crystallized intelligence on the other side. Considering the long-term effects of Conscientiousness and Openness on the development of intellectual abilities, Chamorro-Premuzic and Furnham (2005) refer to these two traits as the ‘‘investment traits’’. In two studies (Moutafi, Furnham, & Paltiel, 2005; Moutafi et al., 2003) a negative correlation between Conscientiousness and intelligence was determined. In order to explain such results the authors proposed a compensation hypothesis, according to which comparatively lower capability in competitive surroundings is compensated with higher levels of Conscientiousness. Besides, it is possible that intelligent individuals do not become more conscientious over time because they rely on abilities that are sufficient for the execution of every-day cognitive tasks. The positive correlation between Openness and crystallized intelligence is expected, considering the fact that Openness is associated with intellectual curiosity, lively imagination and flexibility in behavior (McCrae & Costa, 1997) which could leads to the higher intellectual involvement and knowledge acquisition. Chamorro-Premuzic, Furnham, and Petrides (2006) tested the basic premise of the two-level model using Eysenck’s personality model. They explored the correlations between Eysenck’s personality dimensions operationalised by Eysenck’s Personality Profiler (EPP; Eysenck, Barrett, Wilson, & Jackson, 1992) as Emotional Stability, Introversion, Caution (low Psychoticism) and Dissimulation and verbal and numeric abilities. The results show that Emotional Stability and Extraversion are positively associated with verbal abilities, while there was no correlation found between the two personality dimensions and numeric ability. Moreover, they found a negative correlation between Caution and numeric abilities. Overall, the results found were consistent with the two-level model. In regards to the conceptual and componential similarities between the Big Five and Cattell’s five global dimensions it seems interesting to evaluate certain premises of the two-level model using Cattell’s model of 16 personality factors. Based on the twolevel conceptual framework (Chamorro-Premuzic & Furnham, 2005), and in consideration of the fluid and crystallized intelligence functions, it could be assumed that Anxiety and Extraversion should be in negative correlation with the results on the fluid and crystallized intelligence tests. In consideration of the fact that fluid intelligence refers to the processing of information and ability to reason and that it is linked with the capacity and efficacy of working memory, solving fluid memory test tasks requires greater cognitive endeavor than solving crystallized intelligence test tasks. Thus, we expect a greater negative correlation between Anxiety and fluid intelligence than between Anxiety and crystallized intelligence. Since fluid intelligence tests are not time constrained, and thus more suited to introverts, we expect a negative correlation between Extraversion and fluid intelligence. Furthermore, Self-Control should be in negative correlation with the fluid intelligence test scores, whereas Independence will be in positive correlation with the crystallized intelligence test scores. Self-Control is conceptually similar to the dimension of Conscientiousness, whereas Independence is similar to the dimension of Openness in the Big Five model. We can predict Tough-Mindedness to be in positive correlation with the fluid intelligence test results. This general factor Cattell named ‘‘Corteria’’, which is shortened from ‘‘cortical alertness’’ and described those individuals who achieve high results in this factor as alert and prone to dealing with problems in a cognitive manner (Cattell, Eber, & Tatsuoka, 1970). 2. Method 2.1. Participants The study was conducted on a group of 105 students of the third grade of three high schools in Sarajevo, Bosnia and Herzegovina. Of the total number of participants 45.7% were males. Average age of the participants was M = 17.26 (SD = 0.94.). 2.2. Measures Raven’s Advanced Progressive Matrices (Raven, Raven, & Court, 1998) measure fluid intelligence. They represent a non-verbal test for the evaluation of the ability to understand complex situations, find meaning in events and of rational perception and thinking. According to Carpenter, Just, and Shell (1990) Raven’s Progressive Matrices measure analytical intelligence, that is the ability to reason and produce a solution for problems involving new pieces of information, without extensive use of an explicit store of declarative knowledge. They consist of two parts. Series I contain 12 items used for practice and lowering test anxiety. Series II consists of 36 items presented in ascending order of complexity (i.e. from easiest to hardest). Work-time is not limited. Mill Hill Vocabulary Scale (Raven, Court, & Raven, 1994) is a companion measure to the Standard Progressive Matrices and assesses reproductive ability, that is, being able to master, recall and reproduce verbal information. It consists of 68 items divided into two segments: Series A (gap filling) and Series B (selection of the correct answer from several offered). The Mill Hill Vocabulary Scale allows the assessment of the ability to store and recall information and knowledge that is accumulated over time by the individual from experiences at home, school, or in the environment and therefore is based on the extensive use of declarative knowledge. With regard to definition of crystallized intelligence (Stankov, 2000) crystallized abilities are typically measured by a vocabulary test. 65 N. Djapo et al. / Personality and Individual Differences 51 (2011) 63–67 Original version of the Mill Hill Vocabulary Scale is translated and adapted into Croatian language (Križan & Matešić, 2001). The Sixteen Personality Factors’ Questionnaire (16PF) was devised by Cattell and associates (Cattell, Cattell, & Cattell, 1993). It is to be used in the assessment of 16 primary personality factors, as well as five global factors. It consists of the 185 items in the form of multiple-choice questions that, except for Factor B, have three options. Primary factors to be measured with the 16PF Questionnaire are: A (Warmth); B (Reasoning); C (Emotional Stability), E (Dominance), F (Liveliness), G (Rule- Consciousness), H (Social Boldness), I (Sensitivity), L (Vigilance), M (Abstractedness), N (Privateness), O (Apprehension), Q1 (Openness to Change), Q2 (SelfReliance), Q3 (Perfectionism), and Q4 (Tension). The five global factors and corresponding primary factors are: Extraversion (A+, F+, H+, N , Q2 ), Anxiety (C , L+, O+,Q4+), Self-Control (F , G+, M , Q3+), Independence (E+, H+, L+, Q1), and Tough-Mindedness (A , I , M , Q1+). The five dimensions of personality were calculated according to the procedures described in the 16PF Questionnaire manual (Russell & Karol, 2000). Table 2 Correlations between fluid and crystallized intelligence and the 16 Personality Factors (in italic are given corresponding five global factors). Gf 2.3. Procedure Participants were tested in an auditorium for the three tests, during two regular school classes. Time needed to solve the tasks of Raven’s Advanced Progressive Matrices and Mill Hill Vocabulary Scale was not limited. 3. Results Gc .284** Warmth (Reserved vs. Warm; Factor A); Extraversion; Tough-Mindedness Reasoning (Concrete vs. Abstract; Factor B) Emotional Stability (Reactive vs. Emotionally Stable; Factor C); Anxiety Dominance (Deferential vs. Dominant; Factor E); Independence Liveliness (Serious vs. Lively; Factor F); Extraversion, SelfControl Rule-Consciousness (Expedient vs. Rule-Conscious; Factor G); Self-Control Social Boldness (Shy vs. Socially Bold; Factor H); Extraversion, Independence Sensitivity (Utilitarian vs. Sensitive; Factor I); ToughMindedness Vigilance (Trusting vs. Vigilant; Factor L); Anxiety; Independence Abstractedness (Grounded vs. Abstracted; Factor M); Self-Control; Tough-Mindedness Privateness (Forthright vs. Private; Factor N); Extraversion Apprehension (Self-Assured vs. Apprehensive; Factor O); Anxiety Openness to Change (Traditional vs. Open to Change; Factor Q1); Independence, Tough-Mindedness Self-Reliance (Group-Oriented vs. Self-Reliant; Factor Q2); Extraversion Perfectionism (Tolerates Disorder vs. Perfectionistic; Factor Q3); Self-Control Tension (Relaxed vs. Tense; Factor Q4); Anxiety .433 .073 *** .028 .418*** .081 .177* .145 .073 .142 .238 * 249** .027 .171(a) .388*** .198* .178* .107 .067 .022 .242** .014 .205* .145 .018 .158 .203* .027 .120 .083 .021 .025 * The correlations between the results on the fluid (Gf) and crystallized (Gc) intelligence tests and five global personality dimensions are presented in Table 1. The fluid intelligence scores were negatively correlated with Extraversion (r = .2121, p < .05) and Self-Control (r = .207, p < .05) and positively with Tough-Mindedness (r = .305, p < .01) while the crystallized intelligence scores were positively correlated with Independence (r = .219, p < .05), and negatively with Tough-Mindedness (r = .216, p < .05). The correlations between Gf and Gc and the 16 personality factors are presented in Table 2. The highest correlation was found between the Gf and the factor of reasoning (B) (r = .433, p < .001). The Gf were negatively correlated with the factors of Warmth (A) (r = .284, p < .01), Rule-Consciousness (G) (r = .238, p < .05), Sensitivity (I) (r = .388, p < .001) and Apprehension (O) (r = .205, p < .05), and positively with the factors of Dominance (E) (r = .177, p < .05), Vigilance (L) (r = .178, p < .05), Privateness (N) (r = .242, p < .01), and Self-Reliance (Q2) (r = .203, p < .05). The Gc were negatively correlated with the factor of Rule-Consciousness (G) (r = .249, p < .01), and positively with factors of Reasoning (B) (r = .418, p < .001), and Sensitivity (I) (r = .198, p < .05), whereas the correlation with the factor of Social Boldness (H) is on the border of statistical significance with p = .05 (r = .171, p = .051). With the aim to assess the joint effect of the five global dimensions of personality on the Gf and Gc, two standard multiple Table 1 Correlations between fluid and crystallized intelligence tests and five global personality dimensions. Gf Extraversion Anxiety Self-Control Independence Tough-Mindedness * ** p < .05. p < .01. .211* .047 .207* .129 .305** Gc .065 .091 .155 .219* .216* p < .05. ** p < .01. *** p < .001. (a) p = .05. Table 3 Standard regressional analysis of five global personality dimensions onto fluid and crystallized intelligence. Variables Gf b Extraversion Anxiety Self-Control Independence Tough-Mindedness F (5,99) R R2 AdjR2 ** *** .329 .126 .230 .366 .396 8.13*** .539 .291 .255 Gc t b 3.452** 1.375 2.630** 3.684*** 4.284*** .065 .111 .162 .142 .165 2.15 .313 .098 .052 t .605 1.070 1.637 1.271 1.587 p < .01. p < .001. regression analyses were performed. The results are shown in Table 3. The results indicate that global dimensions of personality was a significant predictor of Gf but not Gc, accounting for 25,5% of variance of fluid intelligence scores. The most significant predictor of Gf was Tough-Mindedness (b = .396), then Independence (b = .366), Extraversion (b = .329) and Self-Control (b = .230). 4. Discussion This study investigates the relationship between five global dimensions and 16 factors of Cattell’s model of personality and 66 N. Djapo et al. / Personality and Individual Differences 51 (2011) 63–67 Gf and Gc. The results were analysed in the light of the two-level conceptual framework model (Chamorro-Premuzic & Furnham, 2005). In line with expectations, some aspects of Anxiety are related to Gf but not with Gc. The results are consistent with the results found in other studies (Hembree, 1988; Zeidner, 1995; Zeidner, 1998). The fact that Anxiety as a global personality dimension was not correlated with Gf is not surprising, as the test results did not have any significant implications for the subjects, who, we assume, did not find the testing situation upsetting. Apprehension (O+), which includes sensitivity, being prone to excessive worry, insecurity and self-criticism, may be indicative of the influence of actual intellectual competence on anxiety as explained in Muller’s (1992) theory, whereas Vigilance (L+) may have a positive effect on a test situation since it blocks reckless decision-making in choosing the task solutions. In line with expectation, Extraversion was negatively correlated with Gf. The results found are consistent with the results found in other studies (Eysenck, 1994; Rawlings & Carnie, 1989). Considering that the testing time was not limited, the test situation was more appropriate for introverts, who indeed reached somewhat higher results on the fluid intelligence test. At the level of primary factors, Gf was negatively correlated with Warmth (A+), and positively with Privateness (N+) and Self-Reliance (Q2+). Reserved (A ), Privateness (N+), and Self – Reliance (Q2) can be connected with a preference for independent work, a focus on one’s own abilities and skills, and dedication to problem solving, all of which are qualities of competitive behavior which the school system encourages. As expected, Self-Control was negatively correlated with Gf. On the primary factors level, Rule-Conscientiousness (G+) was negatively correlated with Gf and with Gc, while Dominance (E+) was positively correlated with Gf. Self-Control is conceptually similar to Conscientiousness in the Big Five model of personality and it is in correlation with all the facets of Conscientiousness: competence, order, dutifulness, achievement striving, self-discipline and deliberation (Russell and Karol, 2000). The results found in our research are consistent with the results found in other studies (Moutafi et al., 2005) and could be considered as support for the hypothesis of compensation (Chamorro-Premuzic et al., 2005). Namely, persons with comparatively lower fluid abilities find it more difficult to deal with challenges, have more problems tackling new situations, or problem-solving, especially in competitive surroundings, and thus compensate for this deficiency with conscientiousness and hard work, dedication, good time management and self-discipline. On the other hand, persons who have high Gf have no overly expressed need to form traits characteristic for Conscientiousness since they possess capacities and abilities that allow them to solve the problems without being so well organised or dedicated to the problem-solving. This mechanism is especially emphasised in surroundings which are not cognitively challenging and in which a more mechanical memory rather than reasoning abilities is more valued. Independence was positively correlated with Gc but not with Gf, which is in line with expectations. Independence may be viewed as a personality trait which has long-term effects on development of intellectual abilities, in particular, crystallized intelligence. Conceptual support for this assumption could be found in Russell and Karol’s (2000) notion that Independence involves a tendency to create and express personal beliefs and try out new things, and that independent persons show intellectual curiosity. The results of our research could be integrated in the assumption of the two-level conceptual framework model. On the primary factors level our study demonstrated that there is a positive correlation between Gf and Dominance (E+) and Vigilance (L+). Dominance can precondition a better position in peer-groups that allows broader possibilities of using surrounding resources whereas Vigilance (L+), as stated, has a positive effect on a test situation. An interesting result was that Tough-Mindedness was positively correlated with Gf, and negatively with Gc. Like Independence, Tough-Mindedness could have long-term effects on the development of intellectual abilities, but different for fluid and for crystallized intelligence. This study reveals negative and relatively high correlations between factors of Warmth (A+) and Sensitivity (I+) with Gf and a positive correlation between Sensitivity (I+) and Gc. Utilitarian personalities (I ) are interested in the issues of functioning of things and are prone to thinking about usefulness and objectivity. One of the possible explanations of this result is that the development of Gf co-varies with the development of utilitarian prone traits. That is, the development of logical reasoning abilities is encouraged by cognitively more demanding surroundings, filled with tasks, problems or questions most frequently directed at understanding of the functioning of things or objects or finding relations between the elements of the problem. On the other hand, Sensitivity (I+) (as a factor conceptually similar to Big Five facets of Openness to new experiences), could be viewed as a personality trait that leads to greater intellectual involvement and knowledge acquisition (Ackerman, 1996). An alternative explanation is that Sensitivity (as well as other characteristics of highly open people) could be a consequence of their high intelligence (Chamorro-Premuzic & Furnham, 2005). In that case, high intellectual ability would pre-exist the development of Sensitivity. The greatest coefficients of correlation were found between the results for the tests of fluid intelligence and the Reasoning factor (B+). Such a correlation was expected, considering that the scale for the B factor consists of 15 issues that all refer to problem-solving abilities. The factor of reasoning on the 16PF Questionnaire is the only factor that was operationalised as a factor of maximum performance, unlike the other factors that were operationalised as typical behavioral factors. Although the Big-Five personality framework dominates the trait approach to personality, present results affirm the robustness of Cattell‘s 16PF model of personality in predicting intelligence constructs, especially Gf. Construct relations are obtained both at the level of 16 primary dimensions of personality as well as at the second-order level. The results of the regression analysis show that all the broad personality factors, apart from Anxiety, are significant predictors of Gf. However, when the same group of the personality factors is introduced into the regression equation for the prediction of the Gc test results, no statistically significant model can be reached. In addition, significant correlations between primary factors and both fluid and crystallized intelligence are obtained. The relatively small number of participants limits the generalisability of the results, whereas the correlational nature of the study does not allow causal conclusions to be drawn on the relations between the variables. However, despite these limitations, the findings of the study are for the most part consistent with results established in other studies, and the interpretation is logically congruent with the direction of correlation between personality factors and intelligence as predicted by Chamorro-Premuzic and Furnham’s model (2005). Therefore, the results of the research additionally support the validity of the two-level conceptual framework model; using a different taxonomy of personality traits, the results found are still consistent with the model’s hypotheses. Still, our research does not enable us to provide a more thorough explanation of the finding that the personality traits account more for fluid rather than crystallized intelligence. What is needed is a longitudinal study which would assess the short- and long-term effects of the psychological and environmental factors on the intertwined dynamics of personality and intelligence. N. 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