Measure performance
Now that we've fit our neural net, let's check performance to see how well our model is predicting new values. There's not a built-in .score()
method like with sklearn
models, so we'll use the r2_score()
function from sklearn.metrics
. This calculates the R\(^2\) score given arguments (y_true, y_predicted)
. We'll also plot our predictions versus actual values again. This will yield some interesting results soon (once we implement our own custom loss function).
Cet exercice fait partie du cours
Machine Learning for Finance in Python
Instructions
- Obtain predictions from
model_1
on the scaled test set data (scaled_test_features
andtest_targets
). - Print the R\(^2\) score on the test set (
test_targets
andtest_preds
). - Plot the
test_preds
versustest_targets
in a scatter plot withplt.scatter()
.
Exercice interactif pratique
Essayez cet exercice en complétant cet exemple de code.
from sklearn.metrics import r2_score
# Calculate R^2 score
train_preds = model_1.predict(scaled_train_features)
test_preds = model_1.predict(____)
print(r2_score(train_targets, train_preds))
print(r2_score(____, ____))
# Plot predictions vs actual
plt.scatter(train_preds, train_targets, label='train')
plt.scatter(____)
plt.legend()
plt.show()