Table 5. Discriminant coefficient, standardized discriminant coefficient, partial F-value, and P-value for each of the 2 variables selected in the stepwise analysis for the discriminant function to separate faces during smiling and resting in the older group.

Facial characteristics to discriminate rest vs. smile postures in the older group	Discriminant coefficient	Standardized discriminant coefficient	Partial F-value	P-value	Structure matrix
Decrease in lower face height during smiling (|Sn-Gn|/|N-Gn|)	-0.39	-0.81	35.13	2E-7	-0.81
Cheek protrusive movement in the buccal and oral regions during smiling (Ex-Ch//z_L1-L2|/L1^L2, left)	-19.34	-0.58	18.26	7E-5	-0.59
Constant	47.27