# The G Factor: The Science of Mental Ability

By Arthur R. Jensen | Go to book overview

Appendix C
Multivariate Analyses of a Nexus
The following multivariate analyses of a small nexus of five interrelated variables are intended only as a didactic example of different ways of looking at a nexus. They merely illustrate what the results of these analyses look like when applied to a real (but small) nexus. The example is not intended to make any particular argument. Detailed computational algorithms for the various types of analysis can be found in textbooks on multivariate statistical methods. The correlation matrix and computational procedure for the path analysis were taken from Li ( 1975, pp. 324-328).The five variables in the nexus, listed in temporal order, are: father's education (FED), father's occupation (FOC), his child's IQ in childhood (CIQ), the child's education as total years of schooling (CED), and the child's adult IQ (CAIQ).
 A. The correlations among these five variables, based on a large sample of white males, aged twenty-five to sixty-four, are shown in Table C.1. B. A principal components PC analysis yields two meaningful components, labeled I and II (see Table C.2). The remaining three PCs have been dropped based on the criterion that their eigenvalues (or latent roots) are less than one. C. Also shown are the multiple correlations (Rs) of each variable with every other variable in the matrix. They indicate the degree to which any given variable in the nexus can be predicted by all of the other variables in the nexus. The proportion of variance that any given variable has in common with all of the other variables is indicated by R2. The fact that all of the loadings on PC I (i.e., the general factor in this matrix) are all fairly large indicates that this is a quite close-knit nexus; the main division among the variables is clear from the opposite signs for the father and child variables in PC II. The multiple R and the R2 for Father's Education are the smallest in the whole set, showing that it is the least well predicted by all of the other variables. The Child's Education

-593-

If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Project items
Notes

#### Cited page

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

#### Cited page

The G Factor: The Science of Mental Ability

Settings

Typeface
Text size
Search within

Look up

#### Look up a word

• Dictionary
• Thesaurus
Please submit a word or phrase above.

Why can't I print more than one page at a time?

While we understand printed pages are helpful to our users, this limitation is necessary to help protect our publishers' copyrighted material and prevent its unlawful distribution. We are sorry for any inconvenience.
Full screen
/ 652

## Cited passage

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

## Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

## Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.