This is my first my R project. I am trying to upload the work i have done. iam using the inbuilt R dataset called “mt cars”
#1)importing the inbuilt dataset "mtcars"
data(mtcars)
#3)saving "mtcars" dataset as a .csv file in the working directory
write.csv(mtcars,"mtcarssaved.csv")
#2)creating a stucture for "mtcars"
str(mtcars)
## 'data.frame': 32 obs. of 11 variables:
## $ mpg : num 21 21 22.8 21.4 18.7 18.1 14.3 24.4 22.8 19.2 ...
## $ cyl : num 6 6 4 6 8 6 8 4 4 6 ...
## $ disp: num 160 160 108 258 360 ...
## $ hp : num 110 110 93 110 175 105 245 62 95 123 ...
## $ drat: num 3.9 3.9 3.85 3.08 3.15 2.76 3.21 3.69 3.92 3.92 ...
## $ wt : num 2.62 2.88 2.32 3.21 3.44 ...
## $ qsec: num 16.5 17 18.6 19.4 17 ...
## $ vs : num 0 0 1 1 0 1 0 1 1 1 ...
## $ am : num 1 1 1 0 0 0 0 0 0 0 ...
## $ gear: num 4 4 4 3 3 3 3 4 4 4 ...
## $ carb: num 4 4 1 1 2 1 4 2 2 4 ...
sink("descrptive statistics.txt")
#4) mean of the variable "mpg" in the mtcars dataset
mean(mtcars$mpg)
## [1] 20.09062
#5)median of the variable "qsec" in mtcras datacars
median(mtcars$qsec)
## [1] 17.71
#6) descriptive statictics for "disp" variable
summary(mtcars$disp)
## Min. 1st Qu. Median Mean 3rd Qu. Max.
## 71.1 120.8 196.3 230.7 326.0 472.0
sink()
#7) save the output as "descriptive data"
#8) correlation between "mpg" and "wt"
cor(mtcars$mpg, mtcars$wt)
## [1] -0.8676594
#9) scatter plot between "disp" and "wt"
scatter.smooth(x=mtcars$disp, y=mtcars$wt, main="dispalcement vs. weight")
#10)regression between "mpg" and "wt"
linearModel <- lm(mpg ~ wt, data=mtcars)
linearModel
##
## Call:
## lm(formula = mpg ~ wt, data = mtcars)
##
## Coefficients:
## (Intercept) wt
## 37.285 -5.344
#convert "cyl" into a factor(categorical variable)
mtcars<-factor(mtcars$cyl)
#checking whether converted or not
str(mtcars)
## Factor w/ 3 levels "4","6","8": 2 2 1 2 3 2 3 1 1 2 ...