psych (version 2.0.9)

Tucker: 9 Cognitive variables discussed by Tucker and Lewis (1973)

Description

Tucker and Lewis (1973) introduced a reliability coefficient for ML factor analysis. Their example data set was previously reported by Tucker (1958) and taken from Thurstone and Thurstone (1941). The correlation matrix is a 9 x 9 for 710 subjects and has two correlated factors of ability: Word Fluency and Verbal.

Usage

data(Tucker)

Format

A data frame with 9 observations on the following 9 variables.

t42

Prefixes

t54

Suffixes

t45

Chicago Reading Test: Vocabulary

t46

Chicago Reading Test: Sentences

t23

First and last letters

t24

First letters

t27

Four letter words

t10

Completion

t51

Same or Opposite

Details

The correlation matrix from Tucker (1958) was used in Tucker and Lewis (1973) for the Tucker-Lewis Index of factoring reliability.

References

L.~Tucker and C.~Lewis. (1973) A reliability coefficient for maximum likelihood factor analysis. Psychometrika, 38(1):1--10.

F.~J. Floyd and K.~F. Widaman. (1995) Factor analysis in the development and refinement of clinical assessment instruments., Psychological Assessment, 7(3):286 -- 299.

Examples

# NOT RUN {
data(Tucker)
fa(Tucker,2,n.obs=710)
omega(Tucker,2)
# }