A Step by Step Guide for SPSS and Exercise Studies

136 Statistical tests
Table 49
Table 50
group means on relaxation and confidence are significantly different. Also, the
Box’s M test (not shown here) is not significant (M ˆ 6.41; F ˆ 1.06; ˆ p .384).
This indicates that the assumption of equal group covariance matrices cannot be
rejected. In support of this conclusion, an inspection of the separate covariance
matrices in Table 50 shows that the covariances between the pairs of variables
are not very different in the two groups.
One significant function emerged which could maximise the differences
between the two qualification groups in the predictors’ scores. Depending on the
data, multiple functions may emerge which are not always significant. In this
example (Table 51) the function is significant, and therefore, you can proceed to
look at the discriminant function coefficients.
Standardised canonical discriminant function coefficients (Table 52) range
from 1 to ‡1. Coefficients above .30 (in absolute terms) are usually
considered to be good predictors. In this case, relaxation and confidence are the
only good predictors of the qualification status. The positive sign indicates that
those who qualified had higher confidence and relaxation than those who failed
to qualify. A significant discriminant function can also be interpreted by looking
at the Structure Matrix (not reported here) which shows the correlations between
the discriminant functions and the predictors. High correlations also indicate
good predictive ability.