In each final school nonresponse adjustment cell c, the school nonresponse adjustment factor SCH_NRAFc was computed as follows:
where
Sc is the set of all eligible sampled schools (participating original and substitute schools, and refusing original schools with nonparticipating or no assigned substitute) in cell c;
Rc is the set of all participating schools within Sc;
SCH_BWTs is the inverse of the school probability of selection;
SCH_TRIMs is the school-level weight trimming factor;
SCHSESWTs is the school-level session assignment weight; and
Xs is the estimated grade enrollment corresponding to the original sampled school.