Vehicle Ownership and Fleet models

Sammanfattning: Vehicle ownership model is an important tool in finding tax strategies as well as reducing the pollution effects based on the forecast results from the model. However, the limitations and shortcomings of the existing vehicle ownership models lead to the low quality forecast in some aspects. Therefore, the thesis surveys the vehicle ownership models as well as vehicle fleet models. The research is mainly about the car ownership and fleet model. The currently used car ownership models in Europe are listed and four models are introduced briefly, including their advantages and disadvantages. The relationship between vehicle ownership and fleet models are also described. One specific car ownership model is used for numerical test. The tested car ownership model is the sub-model in Sampers’ in Sweden. This model consists of individual entry and exit probability of car ownership. The estimation data is the same as the data used in Matstoms (2002), which includes the information of the number of cars for different age, gender, income level, and the petrol price, GDP, from 1980 to 1995 in Stockholm, Solna and Sundbyberg. The software used for model estimation is SPSS. The following part is to validate the estimation results and find out the sensitivity of each variable by doing forecasting in Stockholm from 1996 to 2010. The sensitivity analysis shows that the car ownership in Stockholm is most sensitive to petrol price and least sensitive to GDP. We recommend removing the GDP variable and test it by using chi-square test. The chi-square test shows that the GDP variable can be removed from the model. Keyword Vehicle ownership, Vehicle fleet, Car ownership, SPSS, Sampers, Nonlinear regression analysis.