MDSS Assessment of Recommendations Study

Since 2012 DOT winter maintenance supervisors using the FHWA pooled fund study maintenance decision support system (PFS MDSS) have participated in an evaluation of the maintenance recommendations generated by the PFS MDSS. A module integrated into the user interface software allowed maintainers to provide simple feedback indicating whether the decision maker accepted or declined an MDSS recommendation and whether the MDSS-derived road weather conditions matched the actual conditions on the user’s route(s). The first three years of the study indicated that MDSS users accepted 80% of the recommendations; however, the results did not provide the PFS MDSS technical panel with an understanding of what factors caused maintenance personnel to decline the remaining 20% of the recommendations.

Over the last two winters the study involved the active participation of a meteorologist who initiated an evaluation of the road weather conditions each time a DOT participant submitted an Assessment of Recommendation report. The objective was to determine what factors were creating a disparity between what MDSS recommended and what users felt was a more appropriate maintenance action plan. The Assessment of Recommendation study made it clear that each situation has its own unique determing factors; however, the factors tend to cluster into four dominant classes: incorrect MDSS analysis and forecast of precipitation (especially snowfall), variances between actual and modeled blowing snow conditions, differences in the observed versus MDSS-derived pavement temperature, and disparities between actual maintenance practices and the configuration settings MDSS uses to simulate maintenance activities on the user’s route(s). This paper discusses the evolution of the Assessment of Recommendation study and looks at the predominant causes for differences between what the MDSS simulation generates and what MDSS users actually observe in the field. It will summarize potential modifications needed to improve the MDSS simulation process but also discuss ways DOT users can use the MDSS tool to achieve more effective decision support guidance.