Index Variables (Pollutants)

API-11 Weights

API-6 Weights

(Factor score coeff. × factor variance)

H₂O

0.047

CO₂

0.053

0.025

CO

0.102

0.111

CH₄

0.070

−0.468

N₂O

0.122

NO₂

0.092

NH₃

0.114

2.016

SO₂

0.122

CH₃OH

0.104

0.203

PM Fine (PM_2.5)

0.138

0.689

PM Respirables (PM₁₀)

0.140