salary<-read.csv("E:\\Data science\\Salary_Data.csv")
View(salary)
dim(salary)
## [1] 30  2
attach(salary)
summary(salary)
##       exp              sal        
##  Min.   : 1.100   Min.   : 37731  
##  1st Qu.: 3.200   1st Qu.: 56721  
##  Median : 4.700   Median : 65237  
##  Mean   : 5.313   Mean   : 76003  
##  3rd Qu.: 7.700   3rd Qu.:100545  
##  Max.   :10.500   Max.   :122391
qqnorm(sal)

windows()
plot(exp,sal)

windows()
cor(sal,exp)
## [1] 0.9782416
m1<-lm("sal~exp",data=salary)
m1
## 
## Call:
## lm(formula = "sal~exp", data = salary)
## 
## Coefficients:
## (Intercept)          exp  
##       25792         9450
summary(m1)
## 
## Call:
## lm(formula = "sal~exp", data = salary)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -7958.0 -4088.5  -459.9  3372.6 11448.0 
## 
## Coefficients:
##             Estimate Std. Error t value Pr(>|t|)    
## (Intercept)  25792.2     2273.1   11.35 5.51e-12 ***
## exp           9450.0      378.8   24.95  < 2e-16 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 5788 on 28 degrees of freedom
## Multiple R-squared:  0.957,  Adjusted R-squared:  0.9554 
## F-statistic: 622.5 on 1 and 28 DF,  p-value: < 2.2e-16
pv<-predict(m1,salary)
pv
##         1         2         3         4         5         6         7 
##  36187.16  38077.15  39967.14  44692.12  46582.12  53197.09  54142.09 
##         8         9        10        11        12        13        14 
##  56032.08  56032.08  60757.06  62647.05  63592.05  63592.05  64537.05 
##        15        16        17        18        19        20        21 
##  68317.03  72097.02  73987.01  75877.00  81546.98  82491.97  90051.94 
##        22        23        24        25        26        27        28 
##  92886.93 100446.90 103281.89 108006.87 110841.86 115566.84 116511.84 
##        29        30 
## 123126.81 125016.80
pv1<-as.data.frame(pv)
pv1
##           pv
## 1   36187.16
## 2   38077.15
## 3   39967.14
## 4   44692.12
## 5   46582.12
## 6   53197.09
## 7   54142.09
## 8   56032.08
## 9   56032.08
## 10  60757.06
## 11  62647.05
## 12  63592.05
## 13  63592.05
## 14  64537.05
## 15  68317.03
## 16  72097.02
## 17  73987.01
## 18  75877.00
## 19  81546.98
## 20  82491.97
## 21  90051.94
## 22  92886.93
## 23 100446.90
## 24 103281.89
## 25 108006.87
## 26 110841.86
## 27 115566.84
## 28 116511.84
## 29 123126.81
## 30 125016.80
final<-cbind(salary,pv1)
final
##     exp    sal        pv
## 1   1.1  39343  36187.16
## 2   1.3  46205  38077.15
## 3   1.5  37731  39967.14
## 4   2.0  43525  44692.12
## 5   2.2  39891  46582.12
## 6   2.9  56642  53197.09
## 7   3.0  60150  54142.09
## 8   3.2  54445  56032.08
## 9   3.2  64445  56032.08
## 10  3.7  57189  60757.06
## 11  3.9  63218  62647.05
## 12  4.0  55794  63592.05
## 13  4.0  56957  63592.05
## 14  4.1  57081  64537.05
## 15  4.5  61111  68317.03
## 16  4.9  67938  72097.02
## 17  5.1  66029  73987.01
## 18  5.3  83088  75877.00
## 19  5.9  81363  81546.98
## 20  6.0  93940  82491.97
## 21  6.8  91738  90051.94
## 22  7.1  98273  92886.93
## 23  7.9 101302 100446.90
## 24  8.2 113812 103281.89
## 25  8.7 109431 108006.87
## 26  9.0 105582 110841.86
## 27  9.5 116969 115566.84
## 28  9.6 112635 116511.84
## 29 10.3 122391 123126.81
## 30 10.5 121872 125016.80