Table 2 Pollutant concentration changes are associated with total bus traffic and proportional clean shifts.

From: Clean fleets, different streets: evaluating the effect of New York City’s clean bus program on changes to estimated ambient air pollution

 

Δ NO

Δ NO2

Δ BC

 

Model 2

Model 3

Model 2

Model 3

Model 2

Model 3

Δ prop clean buses

−0.04947a (−0.0911, -0.00787)

−0.0176 (-0.0617, 0.02660)

-0.01084a (−0.01587, -0.00580)

−0.00758a (−0.01293, −2.2e−03)

7.1e−05a (2.4e−05, 1.2e−04)

4.7e−05 (−3.1e−06, 9.8e−05)

Total traffic 2010b

−0.00069 (−0.0016, 0.00025)

−0.0003 (−0.0013, 0.00066)

−0.00014a (−0.00026, −0.00003)

−0.00010 (−0.00022, 1.2e−05)

−1.8e−07 (−1.3e−06, 9.0e−07)

−4.8e−07 (−1.6e−06, 6.2e−07)

Truck route

−0.03518a (−0.0530, −0.01734)

−0.0203a (−0.0394, −0.00114)

0.00163 (−0.00053, 0.00379)

0.00315a (0.00083, 5.5e−03)

3.3e−05a (1.3e−05, 5.4e−05)

2.2e−05a (2.1e−07, 4.4e−05)

Bus VMT 2009b

 

−0.0020a (−0.0030, −0.00109)

 

−0.00021a (−0.00032, −9.3e−05)

 

1.5e−06a (4.4e−07, 2.6e−06)

  1. Beta coefficients and 95% confidence intervals presented. Negative coefficients indicate that pollutant concentrations declined more quickly with increasing levels of the independent variable, while positive coefficients indicate that increasing levels of the independent variable were associated with slower declines in pollutant concentrations.
  2. aAssociation significant at p < 0.05.
  3. bLog-transformed variable.
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