ktra03

data(airquality)

airquality <- na.omit(airquality)

model <- lm(Ozone ~ ., data = airquality)
summary(model)

## 
## Call:
## lm(formula = Ozone ~ ., data = airquality)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -37.014 -12.284  -3.302   8.454  95.348 
## 
## Coefficients:
##              Estimate Std. Error t value Pr(>|t|)    
## (Intercept) -64.11632   23.48249  -2.730  0.00742 ** 
## Solar.R       0.05027    0.02342   2.147  0.03411 *  
## Wind         -3.31844    0.64451  -5.149 1.23e-06 ***
## Temp          1.89579    0.27389   6.922 3.66e-10 ***
## Month        -3.03996    1.51346  -2.009  0.04714 *  
## Day           0.27388    0.22967   1.192  0.23576    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 20.86 on 105 degrees of freedom
## Multiple R-squared:  0.6249, Adjusted R-squared:  0.6071 
## F-statistic: 34.99 on 5 and 105 DF,  p-value: < 2.2e-16

predictions <- predict(model, airquality)
mae <- mean(abs(predictions - airquality$Ozone))
print(mae)

## [1] 14.78897

options(repos = c(CRAN = "https://cloud.r-project.org/"))
install.packages("mlbench")

## Installing package into 'C:/Users/nguye/AppData/Local/R/win-library/4.4'
## (as 'lib' is unspecified)

## package 'mlbench' successfully unpacked and MD5 sums checked

## Warning: cannot remove prior installation of package 'mlbench'

## Warning in file.copy(savedcopy, lib, recursive = TRUE): problem copying
## C:\Users\nguye\AppData\Local\R\win-library\4.4\00LOCK\mlbench\libs\x64\mlbench.dll
## to C:\Users\nguye\AppData\Local\R\win-library\4.4\mlbench\libs\x64\mlbench.dll:
## Permission denied

## Warning: restored 'mlbench'

## 
## The downloaded binary packages are in
##  C:\Users\nguye\AppData\Local\Temp\RtmpU7QHr7\downloaded_packages

install.packages("caTools")

## Installing package into 'C:/Users/nguye/AppData/Local/R/win-library/4.4'
## (as 'lib' is unspecified)

## package 'caTools' successfully unpacked and MD5 sums checked

## Warning: cannot remove prior installation of package 'caTools'

## Warning in file.copy(savedcopy, lib, recursive = TRUE): problem copying
## C:\Users\nguye\AppData\Local\R\win-library\4.4\00LOCK\caTools\libs\x64\caTools.dll
## to C:\Users\nguye\AppData\Local\R\win-library\4.4\caTools\libs\x64\caTools.dll:
## Permission denied

## Warning: restored 'caTools'

## 
## The downloaded binary packages are in
##  C:\Users\nguye\AppData\Local\Temp\RtmpU7QHr7\downloaded_packages

install.packages("pROC")

## Installing package into 'C:/Users/nguye/AppData/Local/R/win-library/4.4'
## (as 'lib' is unspecified)

## package 'pROC' successfully unpacked and MD5 sums checked

## Warning: cannot remove prior installation of package 'pROC'

## Warning in file.copy(savedcopy, lib, recursive = TRUE): problem copying
## C:\Users\nguye\AppData\Local\R\win-library\4.4\00LOCK\pROC\libs\x64\pROC.dll to
## C:\Users\nguye\AppData\Local\R\win-library\4.4\pROC\libs\x64\pROC.dll:
## Permission denied

## Warning: restored 'pROC'

## 
## The downloaded binary packages are in
##  C:\Users\nguye\AppData\Local\Temp\RtmpU7QHr7\downloaded_packages

library(mlbench)

## Warning: package 'mlbench' was built under R version 4.4.3

library(caTools)

## Warning: package 'caTools' was built under R version 4.4.3

library(pROC)

## Warning: package 'pROC' was built under R version 4.4.3

## Type 'citation("pROC")' for a citation.

## 
## Attaching package: 'pROC'

## The following objects are masked from 'package:stats':
## 
##     cov, smooth, var

data("PimaIndiansDiabetes")

set.seed(123)
split <- sample.split(PimaIndiansDiabetes$diabetes, SplitRatio = 0.7)
train_data <- subset(PimaIndiansDiabetes, split == TRUE)
test_data <- subset(PimaIndiansDiabetes, split == FALSE)

model <- glm(diabetes ~ ., data = train_data, family = binomial)

predictions <- predict(model, test_data, type = "response")

roc_curve <- roc(test_data$diabetes, predictions)

## Setting levels: control = neg, case = pos

## Setting direction: controls < cases

auc_value <- auc(roc_curve)

print(paste("AUC:", auc_value))

## [1] "AUC: 0.783833333333333"

plot(roc_curve, col = "blue", main = "ROC Curve")