. Author manuscript; available in PMC: 2012 Jan 9.

Published in final edited form as: Aerosol Sci Technol. 2011 Sep;45(9):1090–1108. doi: 10.1080/02786826.2011.581256

TABLE 7.

Site-specific instrumental regression estimates for PM₁₀

Covariates	14	17	60	All sites
Ln(AOD_MODIS) = f (Factors 1, 2, and 3)	0.908^*** (0.630–1.186)	1.051^*** (0.802–1.300)	1.188^*** (0.896–1.480)	0.972^*** (0.798–1.146)
Sin(month since January 2000/2006)	–0.209*** (–0.338–−0.080)	–0.272*** (–0.427– −0.117)	0.0939 (–0.042–0.230)	–0.127*** (–0.213–−0.041)
Cos(month since January 2000/2006)	0.350^** (0.062–0.638)	0.229^* (–0.020–0.478)	0.643^*** (0.386–0.900)	0.368^*** (0.201–0.535)
Season dummy (1 for June, July, and August, 0 for the rest)	0.122 (–0.211–0.455)	–0.271 (–0.592–0.050)	–0.061 (–0.294–0.172)	–0.0963 (–0.281–0.088)
Constant	4.354^*** (3.903–.805)	4.857^*** (4.406–5.308)	4.925^*** (4.511–5.339)	4.591^*** (4.313–4.869)
Observations	244	276	378	898

^***

p < 0.01.

^**

p < 0.05.

p < 0.1.

Note: Factor 1 = positively correlated surface temperature, dew point, relative humidity, and negative visibility; Factor 2 = relative humidity inversely associated with surface temperature; and Factor 3 = atmospheric pressure inversely associated with wind speed (see Table 5 for details). 95% confidence limits (CIs) in parentheses.