Bridges We saw in this chapter that in a certain town, older bridges were in worse condition than newer ones. The given town is a rural area. Is this relationship true in cities 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 a particular city.

a) This city defines any bridge with a condition score less than 5 as deficient. What does this model predict for the condition scores of bridges in the city?

b) Our earlier model found that the condition of bridges in Tompkins County was decreasing at about 0.025 per year.

What does this model say about bridges in this city?

c) How much faith would you place in this model? Explain.

6 Condition 4 3+ 30 60 90 120 Age@Inspection Dependent variable is Condition R-squared = 2.6% s = 0.6708 Variable Coefficient Intercept 4.95147 Age@Inspection -0.00481