ABSTRACT

Montgomery), and it is a realistic introduction to probability theory, as also shown by the study of VDW (German Machine Tool Builder Builders Association) on operational dependability (Günnel et al., 2014). At the German Social Accident Insurance Scheme (BAuA 2010), the accident figures are recorded as frequencies, too, (with histograms), and they show two important results:

− a continuous improvement in safety due to decreased relative frequencies,

− an almost constant mutual relative percentage content of frequencies for individual degrees of seriousness (accident pyramids).