文档介绍：R语言回归分析和方差分析上机
M3=lm(sbp ~weight+age)
summary(M3)
Call:
lm(formula = sbp ~ weight + age)
Residuals:
Min pred=predict(M1,new1,
+interval="prediction",level=)
print()
fit lwr upr
new2=(age=60)
=predict(M2,new2,interval="predictio+n",level=)
print()
fit lwr upr
new3=(weight=160,age=60)
=predict(M2,new3,interval="prediction",level=)
print()
fit lwr upr
new1=(weight=160)
=predict(M1,new1,interval="conf",level=)
print()
fit lwr upr
new2=(age=60) =predict(M2,new2,interval="conf",level=)
print()
fit lwr upr
new3=(weight=160,age=60)
=predict(M3,new3,interval="conf",level=)
print()
fit lwr upr
-way ANOVA
(wghtcat)
[1] TRUE
> levels(wghtcat)
[1] "< 140" "> 200" "140-170" "170-200"
> (agec)
[1] TRUE
> levels(agec)
[1] "35-40" "41-45" "46-50" "51-55" "56-60"
Analysis of Variance
boxplot(sbp ~ wghtcat, ylab = "sbp",xlab="wghtcat")
stripchart(sbp ~ wghtcat,vertical=TRUE,ylab = "sbp",xlab="wghtcat")
boxplot(sbp ~ agec, ylab ="sbp",xlab="agec")
stripchart(sbp ~ agec,vertical=TRUE,ylab = "sbp",xlab="agec")
by(sbp, wghtcat, FUN=meansd)
wghtcat: < 140
mean sd
--------------------------------------
wghtcat: > 200
mean sd
--------------------------------------
wghtcat: 140-170
mean sd
--------------------------------------
wghtcat: 170-200
mean sd
by(sbp, agec, FUN=meansd)
agec: 35-40