Time-dependent equation theoretical background

In chapter three, the theoretical background to all the potential macro-factors that could contribute to road accidents was presented. The relationship between each factor and the probability that road accidents may occur on the national level was conducted. One special criterion to select suitable indicators was used. This has enabled me to determine the key macro-performance indicators in road safety. It has become clear that the chosen indicators must be easy, available, measurable, and comparable worldwide. Moreover, these indicators must be able to indicate/monitor the country s progress over time in road safety and allow international comparisons. The obtained set of indicators was listed and summarised in Table 3.2. The next step was to understand and explain the main published macroscopic studies and models that are used in describing and comparing the road safety development internationally. I have divided the reviewed models into cross-sectional models (time-independent models) and (time-dependent models). A starting point in this direction was to investigate Smeed s equation, particularly in the relation between motorisation and fatality rates. Several models for... 

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