목차 1. model evaluation in-sample evaluation tells us how well our model will fit the data used to train it. problem is that it's not sure how well the trained model can be worked to predict new data. Therefore we should make data splited, two ways in-sample data(training data) and out-of sample data(test set). training/testing sets train_test_split() x_train1, x_test1, y_train1, y_test1 = train_..
