The unquantified benefits for ozone and PM fall into two  (1) those for which the scientific literature does not provide an established Concentration-Response (C-R) function capable of estimating health effects with reasonable certainty and (2) those effects that may double-count benefits (e.g.
Some of the unquantified benefits fall into multiple categories. 
mnli hypothesis: Some of the unquantified benefits fall into multiple categories.  premise: The unquantified benefits for ozone and PM fall into two  (1) those for which the scientific literature does not provide an established Concentration-Response (C-R) function capable of estimating health effects with reasonable certainty and (2) those effects that may double-count benefits (e.g.