The stratified sample furnished by WisDOT and the participants recruited by the WSRL provided a sample adequate for purposes of fulfilling the objectives of Phase III. The sample as furnished by the DOT was skewed towards better pavement quality based on PDI. However, the sample based on IRI was skewed toward poorer quality pavements. The team believes this shows a balanced sample, and the differences in pavement quality between the two indices are the result of the IRI boundaries for the categories. The categories in the two indices should be in closer agreement, although they measure different characteristics.
Overall, the goals of Phase III were met and numerous relationships explored to help WisDOT answer questions about satisfaction with given pavement improvement thresholds and policies. Trust in the DOT and many other variables, again, as in Phase II, help explain just how complicated satisfaction with pavements can be, and what other beliefs and demographics affect trust and satisfaction
