Ability and Intelligence Tests

Description

Six tests were given to 112 individuals. The covariance matrix is given in this object.

Usage

ability.cov

Details

The tests are described as

general:

a non-verbal measure of general intelligence using Cattell's culture-fair test.

picture:

a picture-completion test

blocks:

block design

maze:

mazes

reading:

reading comprehension

vocab:

vocabulary

Bartholomew gives both covariance and correlation matrices, but these are inconsistent. Neither are in the original paper.

Source

⁠Bartholomew D. J. (1987). Latent Variable Models and Factor Analysis. Griffin. ISBN 9780195206159.

⁠Bartholomew D. J., Knott M. (1999). Latent Variable Analysis and Factor Analysis, Second edition. Arnold, London. ISBN 034069243X.

References

⁠Smith G. A., Stanley G. (1983). “Clocking g: Relating Intelligence and Measures of Timed Performance.” Intelligence, 7(4), 353–368. doi:10.1016/0160-2896(83)90010-7.

Examples

require(stats)
(ability.FA <- factanal(factors = 1, covmat = ability.cov))
update(ability.FA, factors = 2)
## The signs of factors and hence the signs of correlations are
## arbitrary with promax rotation.
update(ability.FA, factors = 2, rotation = "promax")