Table 5.
ANOVA and descriptive statistics of AFAR-identified facial expressions over the entire FFSF
| Measures | Effect | M | SD | F | df1 | df2 | p | ηp2 | Power (1- β error prob.) | |
|---|---|---|---|---|---|---|---|---|---|---|
|
| ||||||||||
| Infant smiling | Episode | FF | .12 | .13 | 22.46 | 2 | 78 | <.001 | .37 | 1.00 |
| SF | .06 | .09 | ||||||||
| RE | .10 | .12 | ||||||||
|
| ||||||||||
| Type | Duchenne | .15 | .14 | 44.43 | 1 | 39 | <.001 | .53 | 1.00 | |
| Non-Duchenne | .04 | .05 | ||||||||
|
| ||||||||||
| Episode x Type | FF Duchenne | .20 | .15 | 11.19 | 2 | 78 | <.001 | .22 | 1.00 | |
| FF Non-Duchenne | .05 | .06 | ||||||||
| SF Duchenne | .09 | .11 | ||||||||
| SF Non-Duchenne | .02 | .04 | ||||||||
| RE Duchenne | .17 | .14 | ||||||||
| RE Non-Duchenne | .03 | .04 | ||||||||
|
| ||||||||||
| Infant cry-faces | Episode | FF | .02 | .05 | 6.15 | 2 | 78 | .003 | .14 | 1.00 |
| SF | .05 | .13 | ||||||||
| RE | .06 | .13 | ||||||||
|
| ||||||||||
| Type | Duchenne | .06 | .14 | 1.56 | 1 | 39 | .219 | .04 | .80 | |
| Non-Duchenne | .03 | .07 | ||||||||
|
| ||||||||||
| Episode x Type | FF Duchenne | .01 | .03 | 5.00 | 2 | 78 | .009 | .11 | 1.00 | |
| FF Non-Duchenne | .03 | .06 | ||||||||
| SF Duchenne | .07 | .17 | ||||||||
| SF Non-Duchenne | .04 | .07 | ||||||||
| RE Duchenne | .10 | .17 | ||||||||
| RE Non-Duchenne | .03 | .06 | ||||||||
|
| ||||||||||
| Mother smiling | Episode a | FF | .42 | .26 | 167.10 | 1.44 | 56.28 | <.001 | .81 | 1.00 |
| SF | .10 | .15 | ||||||||
| RE | .36 | .22 | ||||||||
|
| ||||||||||
| Type | Duchenne | .36 | .30 | 12.20 | 1 | 39 | .001 | .24 | 1.00 | |
| Non-Duchenne | .22 | .18 | ||||||||
|
| ||||||||||
| Episode x Type | FF Duchenne | .58 | .23 | 31.36 | 2 | 78 | <.001 | .45 | 1.00 | |
| FF Non-Duchenne | .25 | .17 | ||||||||
| SF Duchenne | .06 | .09 | ||||||||
| SF Non-Duchenne | .14 | .18 | ||||||||
| RE Duchenne | .45 | .24 | ||||||||
| RE Non-Duchenne | .28 | .16 | ||||||||
Note: Statistics were computed using the proportions of infant smiling and cry-faces and mother smiling during the full 2-minute episodes of the FFSF. Raw means and standard deviations are reported. Episode: main effect of episode (FF vs. SF vs. RE); Type: main effect of type of expression (Duchenne vs. Non-Duchenne expressions); Episode x Type: interaction effect of episode by type of expression. Post-hoc power analysis was performed using G*Power 3.1. ηp2 = Partial eta squared.
As the assumption of sphericity was violated for the main effect of episode on mother smiling (Mauchly’s W = .61, p < .001), degrees of freedom were corrected using a Greenhouse-Geisser correction (ε = .72). Assumption of sphericity was met for the main effects and interaction effect on infant smiling and cry-faces, and for the interaction effect on mother smiling (Mauchly’s Ws > .90, ps > .05). Linear mixed-effects analyses yielded conclusions identical to those based on the current results.