This document was produced under the auspices of the Canadian Strategic Highway Research Program (C-SHRP). C-SHRP was initiated in 1987 as a cooperative effort of the Federal, Provincial and Territorial governments of Canada to improve the performance, durability and safety of highways. Financial support for C-SHRP and for this project was provided by the C-SHRP sponsors.

C-SHRP's involvement with Bayesian regression modelling originated with the development of a data analysis plan for the Canadian Long Term Pavement Performance (C-LTPP) project in 1990. A Bayesian regression approach was adopted in C-LTPP to overcome a small sample size problem and to produce early modelling results (after only 5 years of performance data) for the benefit of the program sponsors. By way of the C-LTPP analysis project, C-SHRP developed Bayesian regression software, a specific modelling methodology and pavement performance prediction models. C-SHRP has promoted the use of the Bayesian software and modelling techniques through numerous briefing sessions and training seminars across Canada as well as through joint modelling applications with eight of the provincial transportation agencies.

Based on feedback received from recent users, C-SHRP recognized that the Bayesian software and methodology would only achieve wide-spread usage within the agencies with the availability of an appropriate user's guide. To this end, the goal of this document is to provide a comprehensive user's guide for building and interpreting Bayesian regression models using the BSTAT and XLBAYES software. This guide and its companion CD-ROM tie together and interpret concepts and examples taken from previous C-SHRP Bayesian activities. The principle audience for the guide are the staff from the provincial transportation agencies but it will be of use to all analysts interested in applying Bayesian regression to a linear modelling problem. The Guide provides a brief overview of Bayesian regression theory and a step by step methodology for carrying out a Bayesian regression application.

This guide documents the Bayesian regression modelling software and model-building procedure developed by C-SHRP from 1990 to 1994. This project was managed by Greg Williams of TAC and undertaken by Dr. Gordon Sparks of Vemax Management Inc. and Dr. Dale Nesbitt of Decision Focus Incorporated.

The following people were directly involved in the preparation of the Bayesian Modelling Guide:

C-SHRP/LTPP Steering Committee

Mike Jackart (Chair)
New Brunswick Department of Transportation

Luc Fréchette (C-SHRP Project Manager)
Transportation Association of Canada

Guy Doré
Ministère des Transports du Québec

Dr. Jerry Hajek
Ministry of Transportation, Ontario

Ray Van Cauwenberghe
Manitoba Highways and Transportation

Al Widger
Saskatchewan Highways and Transportation

Greg Williams
Transportation Association of Canada

This guide was written and its companion CD-ROM produced under contract by Doug Kaweski and Mark Nickeson of SilverRidge Communications Inc.