220411

data(iris)
head(iris)

##   Sepal.Length Sepal.Width Petal.Length Petal.Width Species
## 1          5.1         3.5          1.4         0.2  setosa
## 2          4.9         3.0          1.4         0.2  setosa
## 3          4.7         3.2          1.3         0.2  setosa
## 4          4.6         3.1          1.5         0.2  setosa
## 5          5.0         3.6          1.4         0.2  setosa
## 6          5.4         3.9          1.7         0.4  setosa

names(iris)

## [1] "Sepal.Length" "Sepal.Width"  "Petal.Length" "Petal.Width"  "Species"

names(iris)<-tolower(names(iris))
names(iris)

## [1] "sepal.length" "sepal.width"  "petal.length" "petal.width"  "species"

names(iris)<-c('sl','sw','pl','pw','sp')
head(iris)

##    sl  sw  pl  pw     sp
## 1 5.1 3.5 1.4 0.2 setosa
## 2 4.9 3.0 1.4 0.2 setosa
## 3 4.7 3.2 1.3 0.2 setosa
## 4 4.6 3.1 1.5 0.2 setosa
## 5 5.0 3.6 1.4 0.2 setosa
## 6 5.4 3.9 1.7 0.4 setosa

m2<-lm(sl~.,data=iris)
summary(m2)

## 
## Call:
## lm(formula = sl ~ ., data = iris)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -0.79424 -0.21874  0.00899  0.20255  0.73103 
## 
## Coefficients:
##              Estimate Std. Error t value Pr(>|t|)    
## (Intercept)   2.17127    0.27979   7.760 1.43e-12 ***
## sw            0.49589    0.08607   5.761 4.87e-08 ***
## pl            0.82924    0.06853  12.101  < 2e-16 ***
## pw           -0.31516    0.15120  -2.084  0.03889 *  
## spversicolor -0.72356    0.24017  -3.013  0.00306 ** 
## spvirginica  -1.02350    0.33373  -3.067  0.00258 ** 
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 0.3068 on 144 degrees of freedom
## Multiple R-squared:  0.8673, Adjusted R-squared:  0.8627 
## F-statistic: 188.3 on 5 and 144 DF,  p-value: < 2.2e-16

options(scipen=999)