main effect


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main effect

[¦mān i′fekt]
(statistics)
The effect of the change in level of one factor in a factorial experiment measured independently of other variables.
References in periodicals archive ?
For the accuracy, neither the main effect of modality ( F [sub](1, 53)= 0.44, P = 0.511, ?2 = 0.01), nor the main effect of experiment ( F [sub](1,53)= 1.23, P = 0.272, ?2 = 0.02), nor the two-way interaction ( F [sub](1, 53)= 0.00, P = 0.993, ?2 = 0), was significant [Figure 2]b.
A repeated measures ANOVA of the P1 latencies revealed a significant main effect of emotion, F(1, 30) = 8.19, p = .008, [[eta].sup.2.sub.p] = .21, with shorter latencies for happy versus angry faces.
Kabuli type Arerti matures significantly latter than Mariye, despite the fact that no statistical difference was observed by the main effect of row spacing.
Significant main effects of both treatment and time in RF (Figure 5), and a significant main effect of time in SM (Figure 6) were observed (p < 0.05).
Table 3: Regions with functional activation that were correlated with performing the task in the scanner (main effect): positive associations are listed first and negative associations are listed next.
For BMD, after only 2 wks there was a main effect of jump training, but the diet did not (P=0.934), and there was no interaction between jump training and high-phosphorus diet (P=0.476).
For seeding rates, main effect 20 kg ha-1 (S3) produced significantly higher CP (0.42%) higher than 15 kg ha-1 (S2) and 0.83% than 10 kg ha-1 (S1) (Table 2) during first year, whereas during second year S3 produced significantly higher CP (0.15%) than S2 and 0.47% higher than S1 (Table 2).
With regard to total FA on new pairs (table 1), a mixed ANOVA of 2 groups x 2 materials only showed a significant main effect of the variable groups ([F.sub.1,58] = 19.94, p<.0001, [[eta].sup.2.sub.p] = 26), indicating that older people committed more FA on new pairs than young people (means of 0.08 and 0.01, respectively).
The term main effect is the average of all of the responses produced by changing the level of a factor.
He said the main effect of Europe's quantitative easing has been lowering long-term interest rates.
The main effect of congruency was significant F(1,13) = 55.22, p < 0.001, MSE = 40766.11, [eta]p2 = .80 such that RTs were faster on congruent (M= 1036 ms) than incongruent (M=1236 ms) stimuli.
(a) Main effect plot of content of the rice husk; (b) Main effect plot of particle size of the rice husk on compressive strength.