Abstract
This paper provides empirical evidence on the methodological and practical issues when modelling signalised
intersections under of informal public transport driver behavioural characteristics. Whilst the minibuses’ (known as
kombis in Zimbabwe) physical and dynamical properties is the same with private cars and therefore can be
classified as homogenous, their driver behavioural characteristics make it a unique transportation mode with
different operational performances as compared to normal private cars. Aggressive driver behaviour and lateral
discipline of driving typify such behaviour. Yet there is scarce literature on how this behaviour violates the
homogeneity assumption and the methodological issues there from.