temp=rep(c(300,500,750,800),c(5,5,5,5))
rst=c(90,92,88,89,92,95,92,88,89,92,96,96,97,94,92,91,90,93,89,88)
temp_factor=factor(temp)
df=data.frame(rst,temp_factor)
aov(rst~temp_factor,df)
Call:
   aov(formula = rst ~ temp_factor, data = df)
Terms:
                temp_factor Residuals
Sum of Squares        78.15     74.40
Deg. of Freedom           3        16

这是正确的。而以下是错误的，这是为什么
temp=rep(c(300,500,750,800),c(5,5,5,5))
rst=c(90,92,88,89,92,95,92,88,89,92,96,96,97,94,92,91,90,93,89,88)
temp_factor=factor(temp)
df=data.frame(cbind(rst,temp_factor))
aov(rst~temp_factor,df)
为什么加上了一句，cbind之后就变成了。。
Call:
   aov(formula = rst ~ temp_factor, data = df)
Terms:
                temp_factor Residuals
Sum of Squares         3.61    148.94
Deg. of Freedom           1        18
Residual standard error: 2.876533