ABSTRACT
In this paper Performance Shaping Factors (PSFs) that occurred most frequently in the analysis of Signals Passed at Danger (SPADs) with the second generation method CAHR are discussed. In order to assess the validity of the identified PSFs, we compare our results with the results obtained from an adapted Why-Because-Analysis of a subset of the same incidents. The relationship and dependencies between the factors are discussed in detail. We put the identified PSFs for SPADs in the context of an existing PSF taxonomy, in the context of a simple model of the railway system and perform a clustering on them. In the last part of the paper we explain how future simulation studies can help to advance in the understanding of the identified PSFs and their relationships.
