TERM
|
SIGNIFICANCE
|
|---|---|
| Cronbach's
Alpha
|
A
measure of internal consistency. Generally used for measures where participants
respond to questions on a scale (1 to 3, 1 to 4, 1 to 5, etc.). Alpha can range
between 0 and 1. If a scale has an alpha above .60, it is usually considered
to be internally consistent.
|
| Kuder-Richardson Reliability
|
Like
Cronbach's alpha, except that it is used for measures in which items only can
be responded to in one of two ways (true/false or
yes/no). Like alpha, can range from 0 to 1. An internally consistent measure
would have a Kuder-Richardson reliability of at least .60
|
| Split-Half Reliability (often based on correlating the "Odds" with the "Evens")
|
An
internally consistent measure should have a split half reliability of at least
.75
|
| Median
Inter-Item Correlation
|
An index of the degree to which individual items correlate with each other. A
median inter-item correlation of .30 usually indicates a high degree of
internal consistency.
|
| Factor Loadings
|
The
degree to which an item appears to be correlated with a factor. Ideally, if
test is supposed to measure two independent factors, half the items should load heavily
(+.40-.80) on the first factor, but have near zero negative loadings on the
second factor. The other should not load on the first factor, but load highly
on second factor. Generally, you expect items measuring certain factor to have
a loading of at least +.30 with factor.
|