How to compare expected and predicted values

Question

from sklearn.datasets import load_boston
boston_data = load_boston()
df = pd.DataFrame(boston_data.data , columns = boston_data.feature_names)
df
x = df
y = boston_data.target
x.columns
reg.fit(x,y)
from sklearn.model_selection import train_test_split
x_train, x_test, y_train, y_test = train_test_split(x, y)
reg.fit(x_train, y_train)
predicted = reg.predict(x_test)
expected = y_test

How to I compare the predicted and expected values to understand the model?

Comments

on basis of RMS value how would i know the accuracy of my model

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Hi@Muhammad,

In RMSE, the errors are squared before they are averaged. This basically implies that RMSE assigns a higher weight to larger errors. This indicates that RMSE is much more useful when large errors are present and they drastically affect the model's performance. It avoids taking the absolute value of the error and this trait is useful in many mathematical calculations. In this metric also, the lower the value, the better is the performance of the model.

Answer 1

The predict() function returns a plain numpy array you can just represent it in a tabular format with original value to see the difference.

To check the accuracy of your model you can check out the RMS value. You can calculate RMS using the below code. 

import numpy as np
print("RMS: %r " % np.sqrt(np.mean((predicted - expected) ** 2)))