Scientific Validity Of the Leadership Matrix   About the Measure of Practical Judgment

Two University of Pennsylvania psychologists have completed the first of a series of studies of the Leadership Matrix. The initial results indicate that its internal consistency is excellent.

In an initial reliability test, Robert J. DeRubeis, Ph.D. and Michael Feeley, Ph.D. used Cronbach's Coefficient Alpha and Spearman-Brown's split-hall method to determine the instrument's internal consistency.

Reliability measures the consistency with which each factor is measuring the same thing, content validity. Does the instrument measure what it purports to measure? (For example, are the "S" adjectives actually measuring the personality construct Sociability as we define it?)

To measure content validity, a rating method is now used every time the Matrix is administered. Those profiled were asked to assign a percentage of accuracy from 0 to 100% to the description of their profile. The accuracy ratings collected to date average 92%.

The following are excerpts from DeRubeis' and Feeley's report:

Correlation Coefficient - Measures the degree to which two separate variables are related on a scale from -1.00 (perfect negative correlation) to +1.00 (perfect positive correlation.) Between the two extremes is a zero (0) correlation, which is the equivalent of the flip of a coin. For personality profiles like the MRA Leadership Matrix, positive correlations of +.80 or higher is considered excellent.

1. Internal Consistency of the Entire Instrument
Coefficient Alpha for all items of the Matrix was found to be +.96. The split-half reliability for all items also was +.96.

2. Internal consistency of the four factors (personality traits).

Ascendancy (A) - Coefficient Alpha = +.90
Split-half = +.80, rising to +.91 when corrected for the number of items of the scale.
Sociability (S) - Coefficient Alpha = +.91
Split-half = +.85, rising to +.91 when corrected for all items.
Emotional Adjustment (E) - Coefficient Alpha = +.85
Split-half = +.84 rising to +.91 when corrected for all items.
Readjustment (R) Coefficient Alpha = +.90
Split- half = +.84, rising to +.91 when corrected for all items.