datasets (version 3.4.3)

ability.cov: 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.

References

Smith, G. A. and Stanley G. (1983) Clocking \(g\): relating intelligence and measures of timed performance. Intelligence, 7, 353--368.

Examples

# NOT RUN {
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")
# }