In connection with Model II, the mediational impact of AT and EI on an association between exogenous variables and AU was investigated. Results from the bootstrapping analysis, as illus- trated in Table 8, showed that these mediating factors significantly mediated the relationship between PU and AU (b 1⁄4 0.064, p , .05; 95% bootstrap CI of 0.013–0.147, respectively; therefore, H12b was supported. In contrast, this result did not prove the indirect effect between PEoU and SN and AU so hypotheses H13b and H14b were not supported.