FREEWAY OPERATIONS AND THE CUSP CATASTROPHE: AN EMPIRICAL ANALYSIS.

Previous empirical work has shown that freeway operations sometimes result in discontinuous data and sometimes do not. Catastrophe theory has recently been proposed as one way of understanding the operations of freeways, which can account for the discontinuities in data. Data from the Queen Elizabeth Way in Ontario are used to test statistically how well the cusp catastrophe can replicate freeway operations. The results are extremely promising, with R**2-values generally above 0. 7, and with results that make physical sense in terms of behavior of traffic on the roadway.