# COMMunicationRESearch.NET

### Site Tools

effect_size_for_anova

# Effect size for ANOVA

 Source Type III Sum of Squares df Mean Square F Sig. Eta2 Etap2 Corrected Model 280 5 56 3.055 0.036 0.459 - Intercept 2400 1 2400 130.909 0 DRIVE 24 1 24 1.309 0.268 0.039 0.068 REWARD 112 2 56 3.055 0.072 0.184 0.253 DRIVE * REWARD 144 2 72 3.927 0.038 0.236 0.304 Error 330 18 18.333 Total 3010 24 Corrected Total 610 23

refer to effect_size.xlsx

## eta square

eta square (h2) value

$\eta^{2} = \displaystyle \frac {\text{SS}_{\text{treatment}}} {\text{SS}_{\text{total}}}$

Total = 3010 = 24 + 112 + 144 + 330 + 2400
Correct Total = 610 = 24 + 112 + 144 + 330
We use corrected total, 610:

DRIVE: 24/610 = 0.039344262 = 0.039
REWARD: 112/610 = 0.183606557 = 0.184
DRIVE*REWARD: 144/610 = 0.236065574 = 0.236
SUM: 0.46

46% of dependent variable is accounted for by the IVs.

## partial eta square

partial eta square (h2p) value

$\eta_{p}^{2} = \displaystyle \frac {\text{SS}_{\text{effect}}} {\text{SS}_{\text{effect}} + \text{SS}_{\text{error}} }$

SSerror = 330

 Effect SSeffect SSerror SSeffect+ SSerror Etap2 Drive 24 330 354 0.068 Reward 112 330 442 0.253 Reward * Drive 144 330 474 0.304