2007 Volume 7 Pages 556-569
The travel behavior is a result of complex decision making process affected by individual’s socioeconomic, mode and trip characteristic as well as unobserved variables. The focus of this research was to identify the unobserved factors influencing travel behavior. Six latent variables named as travel factors were identified through factor analysis. Structural equation modeling (SEM) was used to identify casual relationship between observed variables and travel factors. It was noted that SEM cannot predict the travel demand but it has ability to express relationships between unobserved and observed variables. Then, travel factors were employed in discrete choice model to consider individual preferences on unobserved variables. It was found that the model with travel factors perform superior than model without travel factors. Conclusively, the further application of these factors in its different forms can effectively measure their effect in the travel demand model.