I am performing a onmibus anova to test for interaction on a dataset with one variable and three factors.
data$fac1
data$fac2
data$fac3
levels(data$fac1)
[1] "1" "2" "3" "4" "5" "6" "7" "8"
[9] "9" "10" "11" "12" "13" "14" "15" "16"
[17] "17""18" "19" "20" "21" "22" "23" "24"
[25] "25""26" "27" "28" "29" "30" "31" "32"
[33] "33" "34" "35" "36" "37" "38" "39" "40"
[41] "41" "42" "43" "44" "45" "46" "47" "48"
[49]
levels(data$fac2)
[1] "1" "2" "3" "4" "5" "6" "7" "8"
levels(data$fac3)
[1] "1" "2" "3"
The second factor is ignored.
The code is below:
anova(lm(var ~ fac1 * fac2 * fac3, data= data))
It returns:
Response: var
Df Sum Sq Mean Sq F value Pr(>F)
fac1 48 31708 660.59 67.043 < 2e-16 ***
fac3 2 279 139.44 14.152 1.4e-06 ***
fac1:fac3 95 10384 109.31 11.094 < 2e-16 ***
Residuals 279 2749 9.85
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
While I expecting something like:
Response: var
Df Sum Sq Mean Sq F value Pr(>F)
fac1 48 31708 660.59 67.043 < 2e-16 ***
fac2 7 --- ------ ----- --- ***
fac3 2 279 139.44 14.152 1.4e-06 ***
fac1:fac2 -- ---- ----- ------ ------- ---
fac1:fac3 95 10384 109.31 11.094 < 2e-16 ***
fac2:fac3 -- ----- ------ ------ ------- ---
Residuals 279 2749 9.85
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Anyone can help?