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Are Travel Demand Forecasting Models Biased because of Uncorrected Spatial Autocorrelation?

This paper discusses spatial autocorrelation in mode choice models, including what kind of bias it introduces and how to remedy the problem. The research shows that a spatially autocorrelated mode choice model, not uncommon because of, in terms of transit characteristics homogeneous neighborhoods, systematically overestimates transit trips from suburban transit-unfriendly areas and underestimates transit trips in the transit-friendly city center. Adding a spatial lag term into the model specification avoids the bias, however, it also changes sampling approaches, requires higher quality household forecast data and complicates forecasting.