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Table 7 Sensitivity analyses including best predictor in each category, all summary measures.

From: Land use regression modeling of intra-urban residential variability in multiple traffic-related air pollutants

Indicator Type Traffic Indicator Estimate(s), p-value(s) from multivariate model Model R2
Null model    R2 = .39
Cumulative density scores: Unweighted traffic density in 100 m
* Obs nearest Major Road (n = 50)
β1 = 0.055 (.004)
β2 = -0.051 (.004)
R2 = .55
  Kernel-weighted density in 50 m
* Obstructed (n = 50)
β1 = 0.034 (.02)
β2 = -0.056 (.002)
R2 = .55
  Density of urban roads (>8500 cars/day) in 200 m
* Obstructed (n = 50)
β1 = 589.4 (.049)
β2 = -760.9 (.0095)
R2 = .52
Summary measures: Total roadway length within:   
  50 meters
* Obstructed (n = 50)
β1 = 0.0144 (<.0001)
β2 = -0.0094 (.005)
R 2 = .56
  100 meters
* Obstructed (n = 50)
β1 = 0.0022 (.34)
β2 = -0.0042 (.005)
R2 = .54
  200 meters
* Obstructed (n = 50)
β1 = 9.28*10-4 (.22)
β2 = -1.25*10-3 (.008)
R2 = .52
  300 meters
* Obstructed (n = 50)
β1 = 2.31*10-4 (.55)
β2 = -6.65*10-4 (.0095)
R2 = .50
  Vehicle Miles Traveled in 200 m
* Obstructed (n = 50)
β1 = 1*10-7 (.21)
β2 = -1*10-7 (.10)
R2 = .47
Distance-based measures: To nearest highway (>19,000/day)
* Obstructed (n = 50)
β1= 0.0176 (.12)
β2 = -0.0195 (.07)
R2 = .50
Characteristics of nearest major road: Trucks per day on nearest major road * Obstructed (n = 34) β1 = .0061 (.01)
β2 = .00596 (.01)
R 2 = .59
  1. Final model bolded; models with diesel-based terms italicized. Traffic indicators for NO 2 .