xoEPC - Jan Mendling

Appendix D
Logistic Regression Results
This appendix gathers details of the logistic regression analysis. In particular, Section D.1
gives a tabular overview of the collinearity analysis of the variables. This analysis led to
a reduction of the variable set in such a way that SN is the only remaining count metric
for size. Section C.2 presents the results of univariate logistic regression models of all
variables of the reduced set. These univariate models show that there is no constant
in a multivariate model required since the constant is not significantly different from
zero in two models (see Wald statistic). Furthermore, the control flow complexity is not
significantly different from zero in both models with and without constant. Therefore, it
is dropped from the variables list. Section D.3 shows results from the multivariate logistic
regression analysis.
D.1 Collinearity Analysis
This section gives the results of the collinearity analysis. The absence of collinearity is
not a hard criterion for the applicability of logistic regression, but it is desirable. In a