6. Egoism Scale (ES)
(Weigel, Hessing, & Ellfers, 1999 ).
Variable
The Egoism Scale emphasizes a direct preference for self-interest over the interests of others. It has roots in
egoism scale of the Dutch Personality Questionnaire (DPQ), and resonates with hostility and cynicism ( Barelds &
Luteijn, 2002; Luteijn, Starren, & Van Dijk, 1985 ).
Description
The instrument comprises 20 items to be rated for degree of agreement. Typically administered in 5-point
Likert-type format, it has also been administered in 3-point format (disagree /C0?/C0agree).
Sample
A Dutch sample ( N5887) was collected by the Netherlands Institute of Public Opinion Research. It was con-
sidered representative of the entire Dutch adult population. An American convenience sample comprised 258
adult participants (mean age 536 years; 57% female) ( Weigel et al., 1999 ).
Reliability
Internal Consistency
Cronbach alpha coefficients were very similar in the Dutch and American samples, ranging from .80 to .84
(Weigel et al., 2009). A similar value of .80 was reported by de Vries and van Kampen (2010) in another Dutch
sample.
Test/C0Retest
The test /C0retest reliability was found to be .73 over a 9-month interval ( Weigel et al., 1999 ).
Validity
Convergent/Concurrent
As expected, the ES correlated positively with all three of the Dark Triad subscales ( de Vries, de Vries, de
Hoogh, & Feij, 2009 ).
Divergent/Discriminant
A comparison of the ES against the Emmons (1987) version of the NPI yielded non-significant correlations in
both the American and Dutch samples (Weigel et al., 2009). Also, its correlation with Machiavellianism was small
(r5.14) (de Vries & van Kampen, 2010 ) and non-significant with the SPI Egotism scale ( de Vries et al., 2009 ).
Construct/Factor Analytic
The authors reported a confirmatory factor analysis supporting a one-factor solution ( Weigel et al., 1999 ). It is
not clear, however, whether or not that analysis was conducted on the same sample where the items were
selected.
Criterion/Predictive
ES scores predicted higher observed frequencies of running stoplights in Rotterdam ( r5.29) and cheating on a
laboratory business management task ( Weigel et al., 1999 ): The latter worked for adult managers ( r5.31) but not
for students ( r52 .05). Self-reported tax evaders scored higher on ES than did non-evaders ( Webley, Cole, &
Eidjar, 2001 ).
Location
Weigel, R.H., Hessing, D.J., & Elffers, H. (1999). Egoism: Concept, measurement and implications for deviance.
Psychology, Crime & Law, 5 , 349/C0378.581 DARK TRIAD MEASURES
V. VICES AND VIRTUES