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Neuroticism and extraversion in different factors of the affect intensity measure
Person. indirid. Diff. Vol. 10, No. 10, pp. 1095-1100, 1989 Printed in Great Britain. All rights reserved
0191-8869/89 $3.00+0.00 Copyright :~ 1989 Maxwell Pergamon Macmillan plc
NEUROTICISM AND EXTRAVERSION IN DIFFERENT FACTORS OF THE AFFECT INTENSITY MEASURE D. G. WILLIAMS Psychology Group, University of Sussex, Arts Building, Falmer, Brighton BNI 9QN, England (Received 21 December 1988)
Summary--The Affect Intensity Measure (AIM) and the Eysenck Personality Questionnaire were completed by 253 subjects. The single summary AIM score correlated positively and significantly with both Neuroticism and Extraversion. Factor analysis of the AIM items found separate positive affect factors and negative affect factors. Extraversion was the leading personality influence in positive affect intensity: Neuroticism was the leading influence in negative affect intensity. Some implications for research on affect intensity and affect variation are discussed.
Larsen and Diener (1987) have argued that those individuals who experience their positive emotions more strongly than do other people will also, at other times, experience their negative emotions more strongly. Thus measures of the characteristic intensity of positive affect can be combined with measures of negative affect intensity to form a single index of (general) affect intensity. This concept of intensity is distinguished from another parameter of mood experience which Larsen and Diener (1985) call hedonic level, defined as the relative frequency of positive rather than negative affect in an individual. In relating these aspects of affect to personality Larsen and Diener (1987) emphasize an association between affect intensity and the disposition of Extraversion, but the position for other major personality dimensions, particularly Neuroticism, is less clear. Earlier reports (Diener, Larsen, Levine and Emmons, 1985; Larsen and Diener, 1985) have claimed that Neuroticism is related to hedonic level but not to affect intensity. However, Larsen and Diener (1987) cite correlations between affect intensity measures and measures of the emotionality temperament and with various distress indicators (anxiety, mood fluctuation, etc.) which would all seem to suggest some involvement of a Neuroticism-like variable in intensity. Indeed, it would be surprising if Neuroticism had no role at all in affect intensity given the long-standing interpretation of Neuroticism as emotional arousability (Eysenck, 1967), even if the emotions concerned are essentially negative emotions. Deriving indices for affect intensity and hedonic level has required repeated assessments of mood in the same individual, which is an expensive and laborious process. However, as a more convenient procedure for intensity, Larsen (Larsen, Diener and Emmons, 1986; Larsen and Diener, 1987) has developed a 40-item questionnaire, the Affect Intensity Questionnaire (AIM). The AIM is reported to have a five-factor structure, but these factors are said to be highly intercorrelated among themselves, so that at the second-order factor level a single major dimension is suggested. Thus only a single score is calculated for the AIM based on the sum of individual item responses after rekeying 11 reversed items. Ss respond using a 6-point format from Never (scored 1) to Always (scored 6). The current report assesses the AIM and examines its relationships with the Eysenck Personality Questionnaire (EPQ: Eysenck and Eysenck, 1975). The EPQ provides measures of the major personality dispositions of Extraversion (E), Neuroticism (N), and Psychoticism (P), together with a Lie scale (L). METHOD
Procedure The AIM and the EPQ were distributed to university students and non-students who answered anonymously. Ss completed the questionnaires in their own time and in unspecified order. Of 468 r.A.LD Ioilo--F
1095
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D . G . WILLIAMS
questionnaire sets sent out 286 were returned (61.1%). Of these, 33 were unusable: 31 because of items missed or failure to keep to the appropriate score format; 2 through high Lie scores combined with bizarrely low scores on the P, E, and N scales. Thus, replies from 253 Ss were analyzed. The AIM was scored by adding the 40 items together after rekeying the 11 reversed items. Full details of the AIM are given in Larsen and Diener (1987).
Subjects The Ss were 69 female and 65 male non-students, and 67 female and 52 male university students. Though the students were younger (M = 23.2 yr) than the non-students (M = 33.6), t = -8.03, df = 251, P < 0.001, and the students had slightly higher P scores (M = 5.03) than the non-students (M = 4.04), t = 2.53, P < 0.05, there were no other measured differences between these groups. Those not currently students included many with university degrees (e.g. teachers, airline pilots, etc.) together with those without: the students, reflecting current trends, included those admitted to university as mature students having left other employment. Thus it seemed reasonable to combine student and non-student groups for further analysis, a decision supported by the statistical homogeneity (Snedecor and Cochran, 1980) of the correlations from the four sex by student status groups for every combination of the five AIM and EPQ scales. The distributions of age, AIM, and EPQ scores for male, female, and combined groups are summarized in Table 1. The males had higher P scores (t = 6.42, P < 0.001), lower N scores (t = -3.81, P < 0.001), lower L scores (t = -2.05, P < 0.05), and lower AIM scores (t = -5.20, P < 0.001) than the female Ss. All of these sex differences are to be expected (Eysenck and Eysenck, 1975; Diener, Sandvik and Larsen, 1985). RESULTS
Correlations between the original scales The P and L scales were negatively correlated for females (r = - 0 . 2 8 1 , P =0.001), males (r = -0.237, P = 0.01), and the total group (r = -0.280, P < 0.001). The E and N scales were negatively correlated for females (r = -0.305, P < 0.001), males (r = -0.372, P < 0.001), and the total group (r = -0.321, P < 0.001). Such correlations between P and L and between E and N scales are not unexpected (Eysenck and Eysenck, 1975). The EPQ scales otherwise were not significantly correlated with each other. The Pearson correlations between AIM scores and age or EPQ scores for females, males, and total Ss are presented in Table 2. AIM scores declined with increasing age, in agreement with the findings of Diener, Sandvik and Larsen (1985). AIM scores were correlated positively with both E and N in males and females alike, with N appearing the stronger influence. However, the negative Table I. Means and standard deviations for female, male, and total Ss: ages, AIM, and EPQ scales Male (N = I 17)
Total (N ,- 253)
Variable
Female (N = 136) Mean
SD
Mean
SD
Mean
SD
Age (yr)
28.74 155.60 3.41 13.39 13.65 5.66
I 1.40 17.91 2.44 4.77 5.24 3.60
28.61 143.26 5.77 13.02 11.02 4.78
1 i.57 19.83 3.39 5.47 5.72 3.19
28.68 149.89 4.50 13.22 12.43 5.25
11.46 19.77 3.14 5.10 5.61 3.44
AIM P E N L
Table 2. AIM correlations with age and EPQ scales
Age P E N L
Females (N ,,, 136)
Males (N = 117)
Total (N =, 253)
-0.256** - 0.021 0.259** 0.348"** 0.064
-0.218" 0.055 0.285"* 0.306*** 0.037
-0.223"** - 0.098 0.270*** 0.375*** 0.088
*P < 0.05; **P < 0.01; ***P < 0 . 0 0 l .
Affect Intensity Measure
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correlation between E and N leads to an understatement of the full relationship of either to the AIM. Their larger individual and joint impact was evident when AIM scores were regressed on the four EPQ scales in a stepwise multiple regression (0.05 significance criterion for inclusion). For the females, AIM scores were a function (R = 0.518) of both N (p = 0.471) and E (fl = 0.402). For the males, AIM scores were also a function (R = 0.527) of both N (fl = 0.478) and E (fl = 0.462). AIM scores for the total sample were a function (R = 0.568) of N (fl = 0.516), E (fl = 0.442), and L (fl = 0.111), accounting for 32.2% (adjusted 31.4%) of the AIM variance: where N and E together could account for 31.0% of the AIM variance (adjusted 30.5%), R = 0.557, F = 56.20, df = 2, 250, P < 0.0001 (for N, /~ -- 0.514; for E, ~ = 0.435).
Factor analysis of the AIM The ratio of Ss to AIM items (6.3) in the total sample was just sufficient to support an exploratory factor analysis for the AIM. Pearson correlations between the 40 AIM items (after rekeying the reversed items) were examined in a principal components factor analysis (SPSS-X; I s in the diagonal). There were nine factors with eigenvalues > 1 (respectively: 8.19, 4.72, 3.30, 1.78, 1.61, 1.43, 1.26, 1.16, 1.05) together accounting for 61.2% of the total variance (respectively: 20.5, 11.8, 8.3, 4.5, 4.0, 3.6, 3.1, 2.9, 2.6%). The slow tail-off in eigenvalues indicates a low signal-to-noise ratio in the questionnaire items. Furthermore, though the coefficient at reliability for the AIM as a whole was 0.882, the average inter-item correlation was only 0.16 I. The proposal for a substantial general factor accounting for much of the total variance finds little support in these unrotated factors. Although all items by definition had positive loadings on the first unrotated factor, of the 22 items with loadings >10.40, 17 were unambiguously concerned only with positive affect (including 3 rekeyed items) and only one (item 30; rank 21; loading = 0.42) was unambiguously concerned only with negative affect ('anxiety'): two of the other four items (6, 10, 15, 32) might be considered as general affect intensity items, item 6 ("my emotions tend to be more intense than those of most people") loaded 0.47 (rank 17), and item 15 ("my friends might say I'm emotional") loaded 0.41 (rank 22). The number of factors worth retaining was ill-defined and so increasing numbers of factors from three to nine were rotated by both the varimax (orthogonal) and Direct Oblimin procedures (the latter with t~ set to zero to permit maximally oblique factors). The 3-factor and 4-factor rotations in each case had all factors with at least six items loading ~>0.40 per factor and all factors had coefficients at reliabilities (based on items loading />0.40) >0.71. By contrast, the 5- to 9-factor rotations all had one or more factors with four or fewer items loading i>0.40 and one or more factors with reliabilities <0.69, and so these solutions were rejected. Following this, the 3- and 4-factor oblique rotations were rejected as providing little improvement over the orthogonal rotations: the maximum absolute correlation between factors occurred in the 4-factor oblimin rotation where Factor 3 correlated 0.231 with Factor 4. The 3-factor and 4-factor varimax solutions were then examined in detail and found to be related: a single negative affect factor (second factor) in the 3-factor solution was divided into two negative affect factors (third and fourth factors) in the 4-factor solution. Coefficient at reliabilities for the factors (based on items loading i>0.40) only slightly favoured the 3-factor structure (at = 0.90, 0.83, 0.82, respectively) over the 4-factor structure (at = 0.90, 0.86, 0.82, 0.73, respectively). In the end the 4-factor varimax rotation appeared the best choice for detailed presentation. Firstly, the meaning of the four factors was clear. Secondly, the 3-factor structure relationship to the EPQ scales can be best understood in the light of the 4-factor results. Lastly, in terms of loadings ~ 0.40, the first of the four factors reappeared unchanged in the 5-factor varimax solution; the second and third factors reappeared unchanged in the 5-, 6-, and 7-factor solutions; the fourth factor reappeared in the 5-factor rotation with three items broken off to alone define the fifth factor. The four varimax factors accounted for 17.4, 10.0, 9.4, and 8.2% of the total variance respectively. The main items defining these four factors are presented in Table 3. Factors 1 and 2 were clearly related to positive affect, and Factors 3 and 4 to negative affect. Factor 1 was concerned predominantly with items describing positive emotions of elation, ecstasy, bursting with joy, and bubbling over with energy: the three minor exceptions describe enjoying being with other people, wanting to share feelings of excitement, and heart racing in anticipation of some exciting event.
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D . G . WILLIAMS
Table 3. AIM items (loading 90.40) defining four varimax-rotated principal component factors (with original reversed items rekeyed) Factor 1
AIM item numbers I, 2, 3, 5, 7", 8, 9*, 10, 14", 18, 20*, 22*, 23, 27", 32, 35", 38 12", /6", 24, 29*, 33", 37*, 40* 4", 11, 17, 21, 25", 30, 36* 6, 15, 19, 26*, 28, 31, 34, 39
2 3 4
Notes: rekeyed items in italics; *items loading 90.65.
Factor 2 contained seven of the eleven (rekeyed) reversed items which in their original form all describe the experience of happiness as of contentment rather than of excitement, exhilaration, or joy. Factor 3 was dominated by three items describing strong reactions of shame or guilt, or of feeling bad when lying, together with three items concerning empathic negative emotions ("sad movies deeply touch me"; " . . . picture of some violent car accident ... makes me feel sick ..."), and one item describing strong feelings of anxiety. Factor 4 contained four of the (rekeyed) reversed items which in their original form describe being or keeping calm, of not overreacting when angry, and having negative moods of mild intensity. The other items concern having more intense emotions than most people, being judged by others as being emotional or 'high-strung', and getting shaky when nervous. Factor scores were generated for each of these factors and correlated with the EPQ scores. The results are presented in Table 4. Note that N and E scales had correlations of opposite sign with all four factors. In multiple regressions (0.05 significance criterion for inclusion), Factor 1 was a function (R ~- 0.544) of E (/~ -- 0.574) and N (0.155); Factor 2 (R = 0.192) of E alone (0.192); Factor 3 (R - 0.627) of N (0.477), L (0.314) and P (-0.158); and, Factor 4 (R -- 0.572) of N (0.546) and L (-0.172). Scale scores derived by simple addition (again with original reversed items rekeyed) of the items in Table 3 correlated highly with corresponding factor scores: r = 0.97, 0.96, 0.90, 0.92, respectively. In the rotated factors only four items (6, 8, 21, 23) had positive loadings >t0.25 on both a negative affect and a positive affect factor. Of these items only item 6 ("my emotions tend to be more intense than those of most people") can be sensibly interpreted as a general affect intensity item. DISCUSSION It could be that the Ss of this study were in some way unusual, or that the demands made by two questionnaires with different scoring formats and much repetition of similar items may have been particularly deleterious to the AIM (Kline, 1986, p. 187): certainly some Ss made their feelings of boredom and irritation known. These results, therefore, might reasonably be regarded as indicative rather than definitive. These reservations aside, the AIM would benefit from some revision. As things stand the best prospect is to improve the distinction between separate positive and negative affect intensity dimensions where, with better item selection, only one dimension of each should emerge. The AIM does not appear to contain a general factor that is sufficiently large nor sufficiently weighted equally by both negative and positive affect items to justify the use of only a single overall score. That there were two positive affect factors in the current results seems due to the reversed items dealing with the experience of happiness as contentment rather than as zestful, aroused, elated or excited. Five of these items involve comparisons of the kind "I feel X rather than Y". The relative length or complexity of these items appears to have led to some randomness in replies from Ss, Table 4. Sex, age and EPQ correlations with scores for four AIM factors Sext Age P E N L
Factor I
Factor 2
Factor 3
Factor 4
0.134" -0.177"* 0.031 0.524*** -0.030 0.053
-0.018 -0.227"** 0.076 0.192"* -0.127" -0.121
0.314"** 0.091 -0.288*** -0.176"* 0.493*'* 0.361"**
0.159" -0.129' -0.014 -0.224"** 0.545*** -0.169"*
*P <0.05, **P < 0.01; **'P < 0.001. tScx: Male = 1; Female = 2.
Affect Intensity Measure
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thus distinguishing the set from the more directly stated positive affect items and muting their association with personality variables. For negative affect, the item subset dealing with guilt and empathy appears more sensitive to both the tough-minded attitudes of high P scorers, who feel little guilt or empathy (Eysenck and Eysenck, 1975), and the social conformity or social desirability features in high L scorers. Furthermore, empathy and guilt, when compared to depression, anxiety or anger, would seem less central to the prototype for negative affect, and the factor structure, aided by the confounding effects of tough-mindedness or conformity, reflected this. These qualifications apart, it seems clear that Extraversion was the leading influence in the positive affect factors and Neuroticism was the leading influence in negative affect. Thus, not only was there a distinction between positive and negative affect intensity in the rotated AIM factors, these factors related primarily to different personality dispositions. The resemblance between this pattern and one found in some research on personality and affect quality (Costa and McCrae, 1980; Clark and Watson, 1988) may be no coincidence. The AIM lacks items making direct reference to affect variability or to the frequency of affect change. Therefore, the AIM essentially defaults to a trait questionnaire concerned with the experience of strong affects whose structure will tend to resemble that of other surveys of affect whose items are expressed in less extreme terms. In such studies, the apparent independence of positive and negative affect seems favoured when Ss integrate their experiences over extended periods of weeks or months (Diener and Emmons, 1985), or when some key descriptors of pleasant affect (e.g. 'happy', 'cheerful') or unpleasant affect (e.g 'depressed', 'unhappy') are absent or few in number in the mood schedule offered to Ss for their replies (Watson, 1988). The AIM, like most personality questionnaires, requires Ss to adopt the extended time perspective to assess their typical feelings. Secondly, the coverage of negative affect in the AIM is selective in that most of the items refer to anxiety, tension or nervousness, whereas there are but three items broadly concerned with guilt or shame (including 'feel pretty bad when . . . I lie'), only one concerned with anger (reversed), and no items at all directly concerned with depression or unhappiness unless an empathy item ("sad movies deeply touch me") is counted. Mood studies which suggest that Extraversion is correlated with positive affect but largely uncorrelated with negative affect, and that Neuroticism is correlated with negative affect but largely uncon.elated with positive affect, tend to be special cases which have used unusual procedures to assess mood (Costa and McCrae, 1980) or have adopted very restricted definitions of negative and positive affect which exclude unhappiness and happiness items (Clark and Watson, 1988; Watson, 1988). When Ss rate the proportion of time each affect is experienced (Wan', Barter and Brownbridge, 1983), when momentary moods are rated (Williams, 1989), or when the personality correlations with depression are taken into account (Watson, Clark and Carey, 1988), a different picture emerges in which Neuroticism is correlated negatively and Extraversion positively with measures of pleasant affect, and Neuroticism is correlated positively and Extraversion negatively with unpleasant affect. The terms pleasant and unpleasant are emphasized here to accord with that higher-order structure for self-reported affect which has two orthogonal bipolar axes, pleasuredispleasure and degree of arousal, where happiness and unhappiness items are key elements in the definition of pleasure-displeasure (Russell, 1980, Figs 5 and 6; Lorr, Shi and Youniss, 1989). Diener, Larsen, Levine and Emmons (1985) would seem to have adopted some such pleasure-displeasure dimension in their original calculations for affect intensity on broad definitions of positive and negative affect, as is particularly evident when intensity is scored for momentary mood (op. cir., Study 2). Effects on mood should be clearest when Neuroticism and Extraversion combine in compatible ways, so that, other influences being equal, the more extreme negative momentary moods should be observed in high N introverts and the more extreme positive moods in low N extraverts: a view reinforced by evidence for some pervasive (chronic) influences of both Neuroticism and Extraversion upon mood (Watson and Clark, 1984; Williams, 1989), which ought to result in a conflation from opposing effects in the momentary moods of high N extraverts. Underwood and Froming (1980), in a study that is particularly relevant to the AIM, have obtained evidence compatible with this account but which indicates a further subtlety. Underwood and Froming devised trait measures of Mood Level (a happy-sad continuum) and Mood Reactivity, where reactivity incorporates both the concepts of intensity and of frequency of mood change. Unlike the AIM the items of the Mood Reactivity scale make explicit references to
1I00
D.G. WILLIAMS
mood variability. The Mood Level and Mood Reactivity scales were found to be negatively correlated so that those claiming poorer mood on average also claimed greater mood reactivity. Level and Reactivity, though related, were distinct concepts so that, for example, scores on the Beck Depression Inventory (Beck, 1967) correlated negatively with Mood Level when Mood Reactivity scores were partialled out, and positively with Mood Reactivity with Mood Level partialled out. As Fliigel (1925, p. 355) put it "those who tend to experience most the extreme degrees of feeling are on the whole less happy than those whose feelings are usually less intense". When personality is added to this account, it is the high N introverts who should show the greatest mood variation, but around a more negative average mood, when compared to low N extraverts: where, perhaps, the happiest moods of high N introverts do not exceed the best moods of the less variable low N extraverts. From this perspective, affect variation would seem a parameter of more interest than affect intensity, with particular difficulties for an intensity concept which is measured by reference to some notional point of neutral mood. Current debates concerning relationships between personality and a variety of mood parameters are complicated and confusing. Whatever their approach, researchers are advised to include the EPQ or the NEO Inventory (Costa and McCrae, 1985) in the battery of questionnaires administered to their Ss so that the separate impact of Extraversion or Neuroticism in mood or performance measures can be examined, with their joint effects assessed using multiple regression procedures. REFERENCES Beck A. T. (1967) Depression. Harper & Row, New York. Clark L. A. and Watson D. (1988) Mood and the mundane: relations between daily life events and self-reported mood. J. Person. soc. Psychol. 54, 296-308. Costa P. T. and McCrae R. R. (1980) Influence of Extraversion and Neuroticism on subjective well-being: happy and unhappy people. J. Person. soc. Psychol. 38, 668-678. Costa P. T. and McCrae R. R. (1985) The NEO Personality Inventory: Manual. Psychological Assessment Resources, Odessa, Florida. Diener E. and Emmons R. A. (1985) The independence of positive and negative affect. J. Person. soc. Psychol. 47, 1105-1117. Diener E., Larscn R. J., Levine S. and Emmons R. A. (1985) Intensity and frequency: dimensions underlying positive and negative affect. J. Person. soc. Psychol. 48, 1253-1265. Diener E., Sandvik E. and Larsen R. J. (1985) Age and sex effects for emotional intensity. Dev. Psychol. 21, 542-546. Eysenck H. J. (1967) The Biological Basis of Personality. Thomas, Springfield, Ill. Eysenck H. J. and Eysenck S. B. G. (1975) Manual of the Eysenck Personality Questionnaire (Junior and Adult). Hodder & Stoughton, Sevenoaks, Kent. Flfigel J. C. (1925) A quantitative study of feeling and emotion in everyday life. Br. J. Psychol. 15, 318-335. Kline P. (1986) A Handbook of Test Construction. Methuen, London. Larsen R. J. and Diener E. (1985) A multitrait-multimethod examination of affect structure: hedonic level and emotional intensity. Person. individ. D/ft. 6, 631-636. Larsen R. J. and Diener E. (1987) Affect intensity as an individual difference characteristic: a review. J. Res. Person. 21, 1-39. Larsen R. J., Diener E. and Emmons R. A. (1986) Affect intensity and reactions to daily life events. J. Person. soc. Psychol. 51, 803-814. Lorr M., Shi A. Q. and Youniss R. P. (1989) A bipolar multifactor conception of mood states. Person. individ. Diff. 10, 155-159. Russell J. A. (1980) A circumplex model of affect. J. Person. soc. Psychol. 39, 1161-1178. Snedecor G. W. and Cochran W. G. (1980) Statistical Methods (7th edn). Iowa State University Press, Ames, Iowa. Underwood B. and Froming W. J. (1980) The Mood Survey: a personality measure of happy and sad moods. J. Person. Assess. 44, 404--414. Wart P., Barter J. and Brownbridge G. (1983) On the independence of positive and negative affect. J. Person. soc. Psychol. 44, 6 ~ 551. Watson D. (1988) The vicissitudes of mood measurement: effects of varying descriptors, time frames, and response formats on measures of positive and negative affect. J. Person. soc. Pychoi. 55, 128-141. Watson D. and Clark L. A. (1984) Negative affectivity: the disposition to experience aversive emotional states. Psychol. Bull. 96, 465-490. Watson D., Clark L. A. and Carey G. (1988) Positive and Negative Affectivity and their relation to anxiety and depressive disorders. J. abnorm. Psychol. 97, 346-353. Williams D. G. (1989) Personality effects in current mood: pervasive or reactive? Person. individ. Diff. In .p~ss.
0191-8869/89 $3.00+0.00 Copyright :~ 1989 Maxwell Pergamon Macmillan plc
NEUROTICISM AND EXTRAVERSION IN DIFFERENT FACTORS OF THE AFFECT INTENSITY MEASURE D. G. WILLIAMS Psychology Group, University of Sussex, Arts Building, Falmer, Brighton BNI 9QN, England (Received 21 December 1988)
Summary--The Affect Intensity Measure (AIM) and the Eysenck Personality Questionnaire were completed by 253 subjects. The single summary AIM score correlated positively and significantly with both Neuroticism and Extraversion. Factor analysis of the AIM items found separate positive affect factors and negative affect factors. Extraversion was the leading personality influence in positive affect intensity: Neuroticism was the leading influence in negative affect intensity. Some implications for research on affect intensity and affect variation are discussed.
Larsen and Diener (1987) have argued that those individuals who experience their positive emotions more strongly than do other people will also, at other times, experience their negative emotions more strongly. Thus measures of the characteristic intensity of positive affect can be combined with measures of negative affect intensity to form a single index of (general) affect intensity. This concept of intensity is distinguished from another parameter of mood experience which Larsen and Diener (1985) call hedonic level, defined as the relative frequency of positive rather than negative affect in an individual. In relating these aspects of affect to personality Larsen and Diener (1987) emphasize an association between affect intensity and the disposition of Extraversion, but the position for other major personality dimensions, particularly Neuroticism, is less clear. Earlier reports (Diener, Larsen, Levine and Emmons, 1985; Larsen and Diener, 1985) have claimed that Neuroticism is related to hedonic level but not to affect intensity. However, Larsen and Diener (1987) cite correlations between affect intensity measures and measures of the emotionality temperament and with various distress indicators (anxiety, mood fluctuation, etc.) which would all seem to suggest some involvement of a Neuroticism-like variable in intensity. Indeed, it would be surprising if Neuroticism had no role at all in affect intensity given the long-standing interpretation of Neuroticism as emotional arousability (Eysenck, 1967), even if the emotions concerned are essentially negative emotions. Deriving indices for affect intensity and hedonic level has required repeated assessments of mood in the same individual, which is an expensive and laborious process. However, as a more convenient procedure for intensity, Larsen (Larsen, Diener and Emmons, 1986; Larsen and Diener, 1987) has developed a 40-item questionnaire, the Affect Intensity Questionnaire (AIM). The AIM is reported to have a five-factor structure, but these factors are said to be highly intercorrelated among themselves, so that at the second-order factor level a single major dimension is suggested. Thus only a single score is calculated for the AIM based on the sum of individual item responses after rekeying 11 reversed items. Ss respond using a 6-point format from Never (scored 1) to Always (scored 6). The current report assesses the AIM and examines its relationships with the Eysenck Personality Questionnaire (EPQ: Eysenck and Eysenck, 1975). The EPQ provides measures of the major personality dispositions of Extraversion (E), Neuroticism (N), and Psychoticism (P), together with a Lie scale (L). METHOD
Procedure The AIM and the EPQ were distributed to university students and non-students who answered anonymously. Ss completed the questionnaires in their own time and in unspecified order. Of 468 r.A.LD Ioilo--F
1095
1096
D . G . WILLIAMS
questionnaire sets sent out 286 were returned (61.1%). Of these, 33 were unusable: 31 because of items missed or failure to keep to the appropriate score format; 2 through high Lie scores combined with bizarrely low scores on the P, E, and N scales. Thus, replies from 253 Ss were analyzed. The AIM was scored by adding the 40 items together after rekeying the 11 reversed items. Full details of the AIM are given in Larsen and Diener (1987).
Subjects The Ss were 69 female and 65 male non-students, and 67 female and 52 male university students. Though the students were younger (M = 23.2 yr) than the non-students (M = 33.6), t = -8.03, df = 251, P < 0.001, and the students had slightly higher P scores (M = 5.03) than the non-students (M = 4.04), t = 2.53, P < 0.05, there were no other measured differences between these groups. Those not currently students included many with university degrees (e.g. teachers, airline pilots, etc.) together with those without: the students, reflecting current trends, included those admitted to university as mature students having left other employment. Thus it seemed reasonable to combine student and non-student groups for further analysis, a decision supported by the statistical homogeneity (Snedecor and Cochran, 1980) of the correlations from the four sex by student status groups for every combination of the five AIM and EPQ scales. The distributions of age, AIM, and EPQ scores for male, female, and combined groups are summarized in Table 1. The males had higher P scores (t = 6.42, P < 0.001), lower N scores (t = -3.81, P < 0.001), lower L scores (t = -2.05, P < 0.05), and lower AIM scores (t = -5.20, P < 0.001) than the female Ss. All of these sex differences are to be expected (Eysenck and Eysenck, 1975; Diener, Sandvik and Larsen, 1985). RESULTS
Correlations between the original scales The P and L scales were negatively correlated for females (r = - 0 . 2 8 1 , P =0.001), males (r = -0.237, P = 0.01), and the total group (r = -0.280, P < 0.001). The E and N scales were negatively correlated for females (r = -0.305, P < 0.001), males (r = -0.372, P < 0.001), and the total group (r = -0.321, P < 0.001). Such correlations between P and L and between E and N scales are not unexpected (Eysenck and Eysenck, 1975). The EPQ scales otherwise were not significantly correlated with each other. The Pearson correlations between AIM scores and age or EPQ scores for females, males, and total Ss are presented in Table 2. AIM scores declined with increasing age, in agreement with the findings of Diener, Sandvik and Larsen (1985). AIM scores were correlated positively with both E and N in males and females alike, with N appearing the stronger influence. However, the negative Table I. Means and standard deviations for female, male, and total Ss: ages, AIM, and EPQ scales Male (N = I 17)
Total (N ,- 253)
Variable
Female (N = 136) Mean
SD
Mean
SD
Mean
SD
Age (yr)
28.74 155.60 3.41 13.39 13.65 5.66
I 1.40 17.91 2.44 4.77 5.24 3.60
28.61 143.26 5.77 13.02 11.02 4.78
1 i.57 19.83 3.39 5.47 5.72 3.19
28.68 149.89 4.50 13.22 12.43 5.25
11.46 19.77 3.14 5.10 5.61 3.44
AIM P E N L
Table 2. AIM correlations with age and EPQ scales
Age P E N L
Females (N ,,, 136)
Males (N = 117)
Total (N =, 253)
-0.256** - 0.021 0.259** 0.348"** 0.064
-0.218" 0.055 0.285"* 0.306*** 0.037
-0.223"** - 0.098 0.270*** 0.375*** 0.088
*P < 0.05; **P < 0.01; ***P < 0 . 0 0 l .
Affect Intensity Measure
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correlation between E and N leads to an understatement of the full relationship of either to the AIM. Their larger individual and joint impact was evident when AIM scores were regressed on the four EPQ scales in a stepwise multiple regression (0.05 significance criterion for inclusion). For the females, AIM scores were a function (R = 0.518) of both N (p = 0.471) and E (fl = 0.402). For the males, AIM scores were also a function (R = 0.527) of both N (fl = 0.478) and E (fl = 0.462). AIM scores for the total sample were a function (R = 0.568) of N (fl = 0.516), E (fl = 0.442), and L (fl = 0.111), accounting for 32.2% (adjusted 31.4%) of the AIM variance: where N and E together could account for 31.0% of the AIM variance (adjusted 30.5%), R = 0.557, F = 56.20, df = 2, 250, P < 0.0001 (for N, /~ -- 0.514; for E, ~ = 0.435).
Factor analysis of the AIM The ratio of Ss to AIM items (6.3) in the total sample was just sufficient to support an exploratory factor analysis for the AIM. Pearson correlations between the 40 AIM items (after rekeying the reversed items) were examined in a principal components factor analysis (SPSS-X; I s in the diagonal). There were nine factors with eigenvalues > 1 (respectively: 8.19, 4.72, 3.30, 1.78, 1.61, 1.43, 1.26, 1.16, 1.05) together accounting for 61.2% of the total variance (respectively: 20.5, 11.8, 8.3, 4.5, 4.0, 3.6, 3.1, 2.9, 2.6%). The slow tail-off in eigenvalues indicates a low signal-to-noise ratio in the questionnaire items. Furthermore, though the coefficient at reliability for the AIM as a whole was 0.882, the average inter-item correlation was only 0.16 I. The proposal for a substantial general factor accounting for much of the total variance finds little support in these unrotated factors. Although all items by definition had positive loadings on the first unrotated factor, of the 22 items with loadings >10.40, 17 were unambiguously concerned only with positive affect (including 3 rekeyed items) and only one (item 30; rank 21; loading = 0.42) was unambiguously concerned only with negative affect ('anxiety'): two of the other four items (6, 10, 15, 32) might be considered as general affect intensity items, item 6 ("my emotions tend to be more intense than those of most people") loaded 0.47 (rank 17), and item 15 ("my friends might say I'm emotional") loaded 0.41 (rank 22). The number of factors worth retaining was ill-defined and so increasing numbers of factors from three to nine were rotated by both the varimax (orthogonal) and Direct Oblimin procedures (the latter with t~ set to zero to permit maximally oblique factors). The 3-factor and 4-factor rotations in each case had all factors with at least six items loading ~>0.40 per factor and all factors had coefficients at reliabilities (based on items loading />0.40) >0.71. By contrast, the 5- to 9-factor rotations all had one or more factors with four or fewer items loading i>0.40 and one or more factors with reliabilities <0.69, and so these solutions were rejected. Following this, the 3- and 4-factor oblique rotations were rejected as providing little improvement over the orthogonal rotations: the maximum absolute correlation between factors occurred in the 4-factor oblimin rotation where Factor 3 correlated 0.231 with Factor 4. The 3-factor and 4-factor varimax solutions were then examined in detail and found to be related: a single negative affect factor (second factor) in the 3-factor solution was divided into two negative affect factors (third and fourth factors) in the 4-factor solution. Coefficient at reliabilities for the factors (based on items loading i>0.40) only slightly favoured the 3-factor structure (at = 0.90, 0.83, 0.82, respectively) over the 4-factor structure (at = 0.90, 0.86, 0.82, 0.73, respectively). In the end the 4-factor varimax rotation appeared the best choice for detailed presentation. Firstly, the meaning of the four factors was clear. Secondly, the 3-factor structure relationship to the EPQ scales can be best understood in the light of the 4-factor results. Lastly, in terms of loadings ~ 0.40, the first of the four factors reappeared unchanged in the 5-factor varimax solution; the second and third factors reappeared unchanged in the 5-, 6-, and 7-factor solutions; the fourth factor reappeared in the 5-factor rotation with three items broken off to alone define the fifth factor. The four varimax factors accounted for 17.4, 10.0, 9.4, and 8.2% of the total variance respectively. The main items defining these four factors are presented in Table 3. Factors 1 and 2 were clearly related to positive affect, and Factors 3 and 4 to negative affect. Factor 1 was concerned predominantly with items describing positive emotions of elation, ecstasy, bursting with joy, and bubbling over with energy: the three minor exceptions describe enjoying being with other people, wanting to share feelings of excitement, and heart racing in anticipation of some exciting event.
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D . G . WILLIAMS
Table 3. AIM items (loading 90.40) defining four varimax-rotated principal component factors (with original reversed items rekeyed) Factor 1
AIM item numbers I, 2, 3, 5, 7", 8, 9*, 10, 14", 18, 20*, 22*, 23, 27", 32, 35", 38 12", /6", 24, 29*, 33", 37*, 40* 4", 11, 17, 21, 25", 30, 36* 6, 15, 19, 26*, 28, 31, 34, 39
2 3 4
Notes: rekeyed items in italics; *items loading 90.65.
Factor 2 contained seven of the eleven (rekeyed) reversed items which in their original form all describe the experience of happiness as of contentment rather than of excitement, exhilaration, or joy. Factor 3 was dominated by three items describing strong reactions of shame or guilt, or of feeling bad when lying, together with three items concerning empathic negative emotions ("sad movies deeply touch me"; " . . . picture of some violent car accident ... makes me feel sick ..."), and one item describing strong feelings of anxiety. Factor 4 contained four of the (rekeyed) reversed items which in their original form describe being or keeping calm, of not overreacting when angry, and having negative moods of mild intensity. The other items concern having more intense emotions than most people, being judged by others as being emotional or 'high-strung', and getting shaky when nervous. Factor scores were generated for each of these factors and correlated with the EPQ scores. The results are presented in Table 4. Note that N and E scales had correlations of opposite sign with all four factors. In multiple regressions (0.05 significance criterion for inclusion), Factor 1 was a function (R ~- 0.544) of E (/~ -- 0.574) and N (0.155); Factor 2 (R = 0.192) of E alone (0.192); Factor 3 (R - 0.627) of N (0.477), L (0.314) and P (-0.158); and, Factor 4 (R -- 0.572) of N (0.546) and L (-0.172). Scale scores derived by simple addition (again with original reversed items rekeyed) of the items in Table 3 correlated highly with corresponding factor scores: r = 0.97, 0.96, 0.90, 0.92, respectively. In the rotated factors only four items (6, 8, 21, 23) had positive loadings >t0.25 on both a negative affect and a positive affect factor. Of these items only item 6 ("my emotions tend to be more intense than those of most people") can be sensibly interpreted as a general affect intensity item. DISCUSSION It could be that the Ss of this study were in some way unusual, or that the demands made by two questionnaires with different scoring formats and much repetition of similar items may have been particularly deleterious to the AIM (Kline, 1986, p. 187): certainly some Ss made their feelings of boredom and irritation known. These results, therefore, might reasonably be regarded as indicative rather than definitive. These reservations aside, the AIM would benefit from some revision. As things stand the best prospect is to improve the distinction between separate positive and negative affect intensity dimensions where, with better item selection, only one dimension of each should emerge. The AIM does not appear to contain a general factor that is sufficiently large nor sufficiently weighted equally by both negative and positive affect items to justify the use of only a single overall score. That there were two positive affect factors in the current results seems due to the reversed items dealing with the experience of happiness as contentment rather than as zestful, aroused, elated or excited. Five of these items involve comparisons of the kind "I feel X rather than Y". The relative length or complexity of these items appears to have led to some randomness in replies from Ss, Table 4. Sex, age and EPQ correlations with scores for four AIM factors Sext Age P E N L
Factor I
Factor 2
Factor 3
Factor 4
0.134" -0.177"* 0.031 0.524*** -0.030 0.053
-0.018 -0.227"** 0.076 0.192"* -0.127" -0.121
0.314"** 0.091 -0.288*** -0.176"* 0.493*'* 0.361"**
0.159" -0.129' -0.014 -0.224"** 0.545*** -0.169"*
*P <0.05, **P < 0.01; **'P < 0.001. tScx: Male = 1; Female = 2.
Affect Intensity Measure
1099
thus distinguishing the set from the more directly stated positive affect items and muting their association with personality variables. For negative affect, the item subset dealing with guilt and empathy appears more sensitive to both the tough-minded attitudes of high P scorers, who feel little guilt or empathy (Eysenck and Eysenck, 1975), and the social conformity or social desirability features in high L scorers. Furthermore, empathy and guilt, when compared to depression, anxiety or anger, would seem less central to the prototype for negative affect, and the factor structure, aided by the confounding effects of tough-mindedness or conformity, reflected this. These qualifications apart, it seems clear that Extraversion was the leading influence in the positive affect factors and Neuroticism was the leading influence in negative affect. Thus, not only was there a distinction between positive and negative affect intensity in the rotated AIM factors, these factors related primarily to different personality dispositions. The resemblance between this pattern and one found in some research on personality and affect quality (Costa and McCrae, 1980; Clark and Watson, 1988) may be no coincidence. The AIM lacks items making direct reference to affect variability or to the frequency of affect change. Therefore, the AIM essentially defaults to a trait questionnaire concerned with the experience of strong affects whose structure will tend to resemble that of other surveys of affect whose items are expressed in less extreme terms. In such studies, the apparent independence of positive and negative affect seems favoured when Ss integrate their experiences over extended periods of weeks or months (Diener and Emmons, 1985), or when some key descriptors of pleasant affect (e.g. 'happy', 'cheerful') or unpleasant affect (e.g 'depressed', 'unhappy') are absent or few in number in the mood schedule offered to Ss for their replies (Watson, 1988). The AIM, like most personality questionnaires, requires Ss to adopt the extended time perspective to assess their typical feelings. Secondly, the coverage of negative affect in the AIM is selective in that most of the items refer to anxiety, tension or nervousness, whereas there are but three items broadly concerned with guilt or shame (including 'feel pretty bad when . . . I lie'), only one concerned with anger (reversed), and no items at all directly concerned with depression or unhappiness unless an empathy item ("sad movies deeply touch me") is counted. Mood studies which suggest that Extraversion is correlated with positive affect but largely uncorrelated with negative affect, and that Neuroticism is correlated with negative affect but largely uncon.elated with positive affect, tend to be special cases which have used unusual procedures to assess mood (Costa and McCrae, 1980) or have adopted very restricted definitions of negative and positive affect which exclude unhappiness and happiness items (Clark and Watson, 1988; Watson, 1988). When Ss rate the proportion of time each affect is experienced (Wan', Barter and Brownbridge, 1983), when momentary moods are rated (Williams, 1989), or when the personality correlations with depression are taken into account (Watson, Clark and Carey, 1988), a different picture emerges in which Neuroticism is correlated negatively and Extraversion positively with measures of pleasant affect, and Neuroticism is correlated positively and Extraversion negatively with unpleasant affect. The terms pleasant and unpleasant are emphasized here to accord with that higher-order structure for self-reported affect which has two orthogonal bipolar axes, pleasuredispleasure and degree of arousal, where happiness and unhappiness items are key elements in the definition of pleasure-displeasure (Russell, 1980, Figs 5 and 6; Lorr, Shi and Youniss, 1989). Diener, Larsen, Levine and Emmons (1985) would seem to have adopted some such pleasure-displeasure dimension in their original calculations for affect intensity on broad definitions of positive and negative affect, as is particularly evident when intensity is scored for momentary mood (op. cir., Study 2). Effects on mood should be clearest when Neuroticism and Extraversion combine in compatible ways, so that, other influences being equal, the more extreme negative momentary moods should be observed in high N introverts and the more extreme positive moods in low N extraverts: a view reinforced by evidence for some pervasive (chronic) influences of both Neuroticism and Extraversion upon mood (Watson and Clark, 1984; Williams, 1989), which ought to result in a conflation from opposing effects in the momentary moods of high N extraverts. Underwood and Froming (1980), in a study that is particularly relevant to the AIM, have obtained evidence compatible with this account but which indicates a further subtlety. Underwood and Froming devised trait measures of Mood Level (a happy-sad continuum) and Mood Reactivity, where reactivity incorporates both the concepts of intensity and of frequency of mood change. Unlike the AIM the items of the Mood Reactivity scale make explicit references to
1I00
D.G. WILLIAMS
mood variability. The Mood Level and Mood Reactivity scales were found to be negatively correlated so that those claiming poorer mood on average also claimed greater mood reactivity. Level and Reactivity, though related, were distinct concepts so that, for example, scores on the Beck Depression Inventory (Beck, 1967) correlated negatively with Mood Level when Mood Reactivity scores were partialled out, and positively with Mood Reactivity with Mood Level partialled out. As Fliigel (1925, p. 355) put it "those who tend to experience most the extreme degrees of feeling are on the whole less happy than those whose feelings are usually less intense". When personality is added to this account, it is the high N introverts who should show the greatest mood variation, but around a more negative average mood, when compared to low N extraverts: where, perhaps, the happiest moods of high N introverts do not exceed the best moods of the less variable low N extraverts. From this perspective, affect variation would seem a parameter of more interest than affect intensity, with particular difficulties for an intensity concept which is measured by reference to some notional point of neutral mood. Current debates concerning relationships between personality and a variety of mood parameters are complicated and confusing. Whatever their approach, researchers are advised to include the EPQ or the NEO Inventory (Costa and McCrae, 1985) in the battery of questionnaires administered to their Ss so that the separate impact of Extraversion or Neuroticism in mood or performance measures can be examined, with their joint effects assessed using multiple regression procedures. REFERENCES Beck A. T. (1967) Depression. Harper & Row, New York. Clark L. A. and Watson D. (1988) Mood and the mundane: relations between daily life events and self-reported mood. J. Person. soc. Psychol. 54, 296-308. Costa P. T. and McCrae R. R. (1980) Influence of Extraversion and Neuroticism on subjective well-being: happy and unhappy people. J. Person. soc. Psychol. 38, 668-678. Costa P. T. and McCrae R. R. (1985) The NEO Personality Inventory: Manual. Psychological Assessment Resources, Odessa, Florida. Diener E. and Emmons R. A. (1985) The independence of positive and negative affect. J. Person. soc. Psychol. 47, 1105-1117. Diener E., Larscn R. J., Levine S. and Emmons R. A. (1985) Intensity and frequency: dimensions underlying positive and negative affect. J. Person. soc. Psychol. 48, 1253-1265. Diener E., Sandvik E. and Larsen R. J. (1985) Age and sex effects for emotional intensity. Dev. Psychol. 21, 542-546. Eysenck H. J. (1967) The Biological Basis of Personality. Thomas, Springfield, Ill. Eysenck H. J. and Eysenck S. B. G. (1975) Manual of the Eysenck Personality Questionnaire (Junior and Adult). Hodder & Stoughton, Sevenoaks, Kent. Flfigel J. C. (1925) A quantitative study of feeling and emotion in everyday life. Br. J. Psychol. 15, 318-335. Kline P. (1986) A Handbook of Test Construction. Methuen, London. Larsen R. J. and Diener E. (1985) A multitrait-multimethod examination of affect structure: hedonic level and emotional intensity. Person. individ. D/ft. 6, 631-636. Larsen R. J. and Diener E. (1987) Affect intensity as an individual difference characteristic: a review. J. Res. Person. 21, 1-39. Larsen R. J., Diener E. and Emmons R. A. (1986) Affect intensity and reactions to daily life events. J. Person. soc. Psychol. 51, 803-814. Lorr M., Shi A. Q. and Youniss R. P. (1989) A bipolar multifactor conception of mood states. Person. individ. Diff. 10, 155-159. Russell J. A. (1980) A circumplex model of affect. J. Person. soc. Psychol. 39, 1161-1178. Snedecor G. W. and Cochran W. G. (1980) Statistical Methods (7th edn). Iowa State University Press, Ames, Iowa. Underwood B. and Froming W. J. (1980) The Mood Survey: a personality measure of happy and sad moods. J. Person. Assess. 44, 404--414. Wart P., Barter J. and Brownbridge G. (1983) On the independence of positive and negative affect. J. Person. soc. Psychol. 44, 6 ~ 551. Watson D. (1988) The vicissitudes of mood measurement: effects of varying descriptors, time frames, and response formats on measures of positive and negative affect. J. Person. soc. Pychoi. 55, 128-141. Watson D. and Clark L. A. (1984) Negative affectivity: the disposition to experience aversive emotional states. Psychol. Bull. 96, 465-490. Watson D., Clark L. A. and Carey G. (1988) Positive and Negative Affectivity and their relation to anxiety and depressive disorders. J. abnorm. Psychol. 97, 346-353. Williams D. G. (1989) Personality effects in current mood: pervasive or reactive? Person. individ. Diff. In .p~ss.