Eysenck Personality Inventory (EPI) data for 3570 participants
The EPI is and has been a very frequently administered personality test with 57 measuring two broad dimensions, Extraversion-Introversion and Stability-Neuroticism, with an additional Lie scale. Developed by Eysenck and Eysenck, 1964. Eventually replaced with the EPQ which measures three broad dimensions. This data set represents 3570 observations collected in the early 1990s at the Personality, Motivation and Cognition lab at Northwestern. An additional data set (epiR) has test and retest information for 474 participants. The data are included here as demonstration of scale construction and test-retest reliability.
data(epi) data(epi.dictionary) data(epiR)
A data frame with 3570 observations on the following 57 variables.
idThe identification number within the study
timeFirst (group testing) or 2nd time (before a lab experiment) for the epiR data set.
studyFour lab based studies and their pretest data
V1a numeric vector
V2a numeric vector
V3a numeric vector
V4a numeric vector
V5a numeric vector
V6a numeric vector
V7a numeric vector
V8a numeric vector
V9a numeric vector
V10a numeric vector
V11a numeric vector
V12a numeric vector
V13a numeric vector
V14a numeric vector
V15a numeric vector
V16a numeric vector
V17a numeric vector
V18a numeric vector
V19a numeric vector
V20a numeric vector
V21a numeric vector
V22a numeric vector
V23a numeric vector
V24a numeric vector
V25a numeric vector
V26a numeric vector
V27a numeric vector
V28a numeric vector
V29a numeric vector
V30a numeric vector
V31a numeric vector
V32a numeric vector
V33a numeric vector
V34a numeric vector
V35a numeric vector
V36a numeric vector
V37a numeric vector
V38a numeric vector
V39a numeric vector
V40a numeric vector
V41a numeric vector
V42a numeric vector
V43a numeric vector
V44a numeric vector
V45a numeric vector
V46a numeric vector
V47a numeric vector
V48a numeric vector
V49a numeric vector
V50a numeric vector
V51a numeric vector
V52a numeric vector
V53a numeric vector
V54a numeric vector
V55a numeric vector
V56a numeric vector
V57a numeric vector
The original data were collected in a group testing framework for screening participants for subsequent studies. The participants were enrolled in an introductory psychology class between Fall, 1991 and Spring, 1995.
The actual items may be found in the epi.dictionary.
The structure of the E scale has been shown by Rocklin and Revelle (1981) to have two subcomponents, Impulsivity and Sociability. These were subsequently used by Revelle, Humphreys, Simon and Gilliland (1980) to examine the relationship between personality, caffeine induced arousal, and cognitive performance.
The epiR data include the original group testing data and matched data for 474 participants collected several weeks later. This is useful for showing that internal consistency estimates (e.g. alpha or omega) can be low even though the test is stable across time. For more demonstrations of the distinction between immediate internal consistency and delayed test-retest reliability see the msqR and sai data sets and testRetest.
Data from the PMC laboratory at Northwestern.
Eysenck, H.J. and Eysenck, S. B.G. (1968). Manual for the Eysenck Personality Inventory.Educational and Industrial Testing Service, San Diego, CA.
Revelle, W. and Humphreys, M. S. and Simon, L. and Gilliland, K. (1980) Interactive effect of personality, time of day, and caffeine: A test of the arousal model, Journal of Experimental Psychology General, 109, 1, 1-31,
data(epi)
epi.keys <- list(E = c("V1", "V3", "V8", "V10", "V13", "V17", "V22", "V25", "V27", "V39",
"V44", "V46", "V49", "V53", "V56", "-V5", "-V15", "-V20", "-V29", "-V32", "-V34","-V37",
"-V41", "-V51"),
N = c( "V2", "V4", "V7", "V9", "V11", "V14", "V16", "V19", "V21", "V23", "V26", "V28",
"V31", "V33", "V35", "V38", "V40","V43", "V45", "V47", "V50", "V52","V55", "V57"),
L = c("V6", "V24", "V36", "-V12", "-V18", "-V30", "-V42", "-V48", "-V54"),
Imp = c( "V1", "V3", "V8", "V10", "V13", "V22", "V39", "-V5", "-V41"),
Soc = c( "V17", "V25", "V27", "V44", "V46", "V53", "-V11", "-V15", "-V20",
"-V29", "-V32", "-V37", "-V51")
)
scores <- psych::scoreItems(epi.keys,epi)
psych::keys.lookup(epi.keys[1:3],epi.dictionary) #show the items and keying information
#a variety of demonstrations (not run) of test retest reliability versus alpha versus omega
E <- psych::selectFromKeys(epi.keys$E)
#look at the testRetest help file for more examplesPlease choose more modern alternatives, such as Google Chrome or Mozilla Firefox.