  The study aimed to evaluate the regression models' performance in predicting
the cost of medical insurance. The Three (3) Regression Models in Machine
Learning namely Linear Regression, Gradient Boosting, and Support Vector
Machine were used. The performance will be evaluated using the metrics RMSE
(Root Mean Square), r2 (R Square), and K-Fold Cross-validation. The study also
sought to pinpoint the feature that would be most important in predicting the
cost of medical insurance.The study is anchored on the knowledge discovery in
databases (KDD) process. (KDD) process refers to the overall process of
discovering useful knowledge from data. It show the performance evaluation
results reveal that among the three (3) Regression models, Gradient boosting
received the highest r2 (R Square) 0.892 and the lowest RMSE (Root Mean Square)
1336.594. Furthermore, the 10-Fold Cross-validation weighted mean findings are
not significantly different from the r2 (R Square) results of the three (3)
regression models. In addition, Exploratory Data Analysis (EDA) using a box
plot of descriptive statistics observed that in the charges and smoker features
the median of one group lies outside of the box of the other group, so there is
a difference between the two groups. It concludes that Gradient boosting
appears to perform better among the three (3) regression models. K-Fold
Cross-Validation concluded that the three (3) regression models are good.
Moreover, Exploratory Data Analysis (EDA) using a box plot of descriptive
statistics ceases that the highest charges are due to the smoker feature.
