The analysis of variance for the 2x2 factorial design with repeated measures in blocks of size 2 uses F ratios to test three hypotheses:
Group effect or RTECH x DOC interaction effect
H0: There is no difference between subjects in Group 1 and subjects in Group 2 with respect to their mean defect rate scores.
Ha: There is a difference between subjects in Group 1 and subjects in Group 2 with respect to their mean defect rate scores.
Main effect RTECH
H0: There is no difference between subjects using PBR and subjects using their usual technique with respect to their mean defect rate scores.
Ha: There is a difference between subjects using PBR and subjects using their usual technique with respect to their mean defect rate scores.
Main effect DOC
H0: There is no difference between subjects reading the ATM document (or NASA_A document) and subjects reading the PG document (or NASA_B document) with respect to their mean defect rate scores.
Ha: There is a difference between subjects reading the ATM document (or NASA_A document) and subjects reading the PG document (or NASA_B document) with respect to their mean defect rate scores.