Table 2.

Coefficient of determination (R²) and p-value between various parameters in Table 1 and ozone mortality coefficients based on the 1-hr, 8-hr, or 24-hr ozone metric.

1-hr [O3]			8-hr [O3]			24-hr [O3]
Parameter	R2	p	R2	p	R2	p
18 cities
Overall air change rate		0.51		< 0.001		0.41		0.004		0.34		0.01
Ozone exposure coefficient		0.58		< 0.001		0.56		< 0.001		0.48		0.001
Fraction with central AC		0.28		0.023		0.09		0.24		0.09		0.22
90 cities
Overall air change rate		0.43		< 0.001		0.50		< 0.001		0.45		< 0.001
Ozone exposure coefficient		0.47		< 0.001		0.63		< 0.001		0.54		< 0.001
Fraction with central AC		0.33		< 0.001		0.17		< 0.001		0.17		< 0.001