demand models for supermarket demand forecasting

Model-based approaches remain an important option for modelling customer demand. while this approach allows to analyse demand using a model based on theoretical arguments, each choice of model is associated with specific  assumptions under which this model is valid. customer demand in retail is typically modelled as a poison-type process, in particular using a negative binomial distribution. poisson-type processes are associated with an exponential inter-arrival time that describes the probability distribution between subsequent events. using a public dataset from a large  supermarket, the analysis of the data shows that while the general assumption of a poisson process is reasonable, the purchasing behaviour strongly depends on the type of product. additionally, customers in this supermarket show astrong preference for a weekly shopping trip.