Regional motorcycle age and emissions inspection performance: A Cox regression analysis

This work combines a motorcycle usage survey from the year 2000 with corresponding records from Taiwan’s Vehicle Registration System to study the relationship between motorcycle disposal age and the implementation of motorcycle inspection and maintenance programs at the regional level. Two models are used to represent the quality of inspection and maintenance program implementation, and analyzed separately. After controlling for other independent predictors, analysis of the first model shows that districts with good inspection performance had a 15% higher hazard rate of motorcycle disposal. Under the second model, a 1% increase in the inspection rate and 1% decrease in the ineligibility rate were also found to raise the hazard rate by 2% and 4% respectively.