A Method of Improving Oral English Teaching Based on PLS-SEM

Table 2

Evaluation indicators.

First-level indicator	Secondary indicators	Details
Reliability	Cronbach’s	Cronbach’s >0.7
	Composite reliability (CR)	CR > 0.7
Validity	Convergent validity [27]	Convergent validity is characterized by average variance extracted (AVE) and factor loadings. It is required that AVE >0.5, factor loading>0.7.
	Discriminant validity [27]	Discriminant validity is indicated by the correlation coefficient between the square root of AVE and latent variables. The model has excellent discriminant validity when the AVE square root value exceeds the latent variable minus the correlation coefficient between latent variables.
Effect	Fit [28]	Reflected by goodness of fit (GOF), when GOF >0.36, the overall fit of the model is considered to be better.
	Explanatory [28]	Characterized by R^2, it is generally required that all latent variables have an R^2 value greater than 0.2.
	Predictive [29]	Redundancy is used to quantify the predictive potential of variables’ internal and external linkages. In general, the redundancy value must be more than 0.33, and the inspection level must be greater than 0.052.