#ANOVA AS LINEAR MODELS
?contrasts
?contr.treatment
options(digits=12)

#++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#CELL MEANS MODEL
#READ STRUCTURED DATA TABLE WITH NUMERIC CODED FACTOR
K=read.table("c:/2008LinearModelsData/KentonFoodCMR.txt")
K
attach(K)

FM=lm(Y~X1+X2+X3+X4-1) #FM for original data K & codes
summary(FM)
model.matrix(FM)
anova(FM)
detach(K)

Kc=data.frame(scale(K,center=T,scale=F))
Kc

attach(Kc)
FM=lm(Y~X1+X2+X3+X4-1)  #FM for centered data Kc
anova(FM)
detach(Kc)
#-------------------------------------------------
#TREATMENTS MODEL IN R
#READ STRUCTURED DATA TABLE WITH NUMERIC CODED FACTOR
K=read.table("c:/2008LinearModelsData/KentonFoodR.txt")
K
attach(K)

Y=Sales
X=factor(Design) # factor() IN DEFAULT SETTING

NM=lm(Y~X)
summary(NM)
anova(NM)
model.matrix(NM)

#++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#UNWEIGHTED FACTOR EFFECTS MODEL
#READ STRUCTURED DATA TABLE WITH NUMERIC CODED FACTOR
Kf=read.table("c:/2008LinearModelsData/KentonFoodFER.txt")
Kf
attach(Kf)

TM=lm(Y~T1+T2+T3)
summary(TM)
anova(TM)
model.matrix(TM)
detach(Kf)
#-------------------------------------------------
#USE OF factor() AS SUM
#READ STRUCTURED DATA TABLE WITH NUMERIC CODED FACTOR
K=read.table("c:/2008LinearModelsData/KentonFoodR.txt")
K
attach(K)
Y=Sales
X=factor(Design)
contrasts(X)=contr.sum #CONVERTS FACTOR CODING TO SUM

SM=lm(Y~X)
summary(SM)
anova(SM)
model.matrix(SM)

#+++++++++++++++++++++++++++++++++++++++++++++++++