We saw in this chapter that in Tompkins County, New York, older bridges were in worse condition than newer ones. Tompkins is a rural area. Is this relationship true in New York City as well? Here are data on the Condition (as measured by the state Department of Transportation Condition Index) and Age at Inspection for bridges in Manhattan–New York County.

a) New York State defines any bridge with a condition score less than 5 as deficient. What does this model predict for the condition scores of New York City bridges?
b) Our earlier model found that the condition of bridges in Tompkins County was decreasing at about 0.0196 per year. What does this model say about New York City bridges?
c) How much faith would you place in this model?

Condition 7 6 5 4 3 2+ 40 80 Age at Inspection Dependent variable is Condition R-squared = 3.9% s = 0.6912 Variable Intercept Age@Inspection 120 Coefficient 5.0112 -0.00513