Consider dput:
structure(list(REAÇÃO = structure(c(0, 1, 0, 0, 1, 0, 1, 1,
0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1,
1, 0, 1, 1, 0, 1, 1), format.spss = "F11.0"), IDADE = structure(c(22,
38, 36, 58, 37, 31, 32, 54, 60, 34, 45, 27, 30, 20, 30, 30, 22,
26, 19, 18, 22, 23, 24, 50, 20, 47, 34, 31, 43, 35, 23, 34, 51,
63, 22, 29), format.spss = "F11.0"), ESCOLARIDADE = structure(c(6,
12, 12, 8, 12, 12, 10, 12, 8, 12, 12, 12, 8, 4, 8, 8, 12, 8,
9, 4, 12, 6, 12, 12, 12, 12, 12, 12, 12, 8, 8, 12, 16, 12, 12,
12), format.spss = "F11.0"), SEXO = structure(c(1, 1, 0, 0, 1,
0, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0,
0, 1, 0, 1, 0, 0, 0, 1, 1, 1), format.spss = "F11.0")), .Names = c("REAÇÃO",
"IDADE", "ESCOLARIDADE", "SEXO"), row.names = c(NA, -36L), class = "data.frame")
where: REAÇÃO is a dependent variable in the model.
Constant: -4.438.
How can I obtain this value using a simple function in R?
For obtain constant term in Discriminant Analysis on R (with library MASS):
groupmean<-(model$prior%*%model$means)
constant<-(groupmean%*%model$scaling)
constant
where model is the lda discriminant expression:
model<-lda(y~x1+x2+xn,data=mydata)
model