Free Practice Quiz Question List

8 Overfitting and Generalization Online Quiz Questions

Use this free practice quiz with 20 questions to review 8 Overfitting and Generalization, test your knowledge, and prepare for your next test or exam.

20 questions
01
Choose one
1 point

A model performs well on its training data but much worse on separate validation data. Which issue is this pattern most likely to indicate?

  1. A

    Underfitting

  2. B

    Overfitting

  3. C

    Reasonable generalization

  4. D

    Insufficient validation data

02
Written response
1 point

A model performs poorly on both its training data and validation data. What modeling problem does this pattern most likely indicate?

03
True or false
1 point

Generalization describes a model's ability to make accurate predictions on previously unseen data.

  1. A

    True

  2. B

    False

04
Choose one
1 point

A very high-degree polynomial passes through every training point, including unusual sales, but predicts prices poorly for other houses. What is the best explanation?

  1. A

    It is underfitting because it cannot match the training points.

  2. B

    It is guaranteed to generalize well because its training error is low.

  3. C

    It may be overfitting by capturing noise or accidental details in the training data.

  4. D

    It is experiencing data leakage because the polynomial has many terms.

05
Choose all
1 point

A model is overfitting. Which actions could help reduce its effective complexity or prevent it from continuing to fit training-data quirks? Select all that apply.

  1. A

    Limit a decision tree's depth.

  2. B

    Use regularization to discourage overly complex parameter values.

  3. C

    Increase the model's flexibility so it can fit every training example more closely.

  4. D

    Use early stopping when validation performance stops improving.

06
Fill in the blank
1 point

Use to compare models or tune settings, and keep the test set for final evaluation.

07
Written response
1 point

What problem can occur if you perform preprocessing or feature selection before splitting a dataset into training, validation, and test sets? Enter the established term.

08
Choose all
1 point

Which practices help prevent data leakage during preprocessing? Select all that apply.

  1. A

    Split the data before preprocessing or feature selection.

  2. B

    Fit scaling or imputation on training data, then apply the learned transformation to validation and test data.

  3. C

    Fit preprocessing steps on the full dataset before creating the training and validation splits.

  4. D

    Use pipelines to keep preprocessing steps within the correct data split.

09
True or false
1 point

In k-fold cross-validation, the model trains on all but one fold and validates on the remaining fold, repeating until every fold has served as validation data.

  1. A

    True

  2. B

    False

10
Choose one
1 point

A model appears to underfit because strong regularization is preventing it from learning useful patterns. Which change is most appropriate?

  1. A

    Increase regularization further.

  2. B

    Reduce excessive regularization.

  3. C

    Limit decision-tree depth even more.

  4. D

    Stop training earlier.

11
Fill in the blank
1 point

In k-fold cross-validation, each fold serves once as the while the model trains on all the other folds.

12
Choose one
1 point

Which tools can help reveal patterns in model performance as training or model settings vary?

  1. A

    A final test score alone, without comparing performance patterns.

  2. B

    A list of training examples in their original order.

  3. C

    Learning curves and validation curves.

  4. D

    The number of parameters, considered without any performance measurements.

13
True or false
1 point

When comparing model performance, lower mean squared error is better, while higher accuracy is better.

  1. A

    True

  2. B

    False

14
Open ended
1 point

Explain how validation and test data should be used during model development, and why repeatedly choosing settings based on test performance can undermine the final evaluation.

15
Written response
1 point

What machine-learning term describes the ability to make accurate predictions on previously unseen data?

16
Choose one
1 point

A deep decision tree performs well on training data but much worse on validation data. Which change most directly addresses the likely problem?

  1. A

    Increase the tree depth so it can fit the training data more closely.

  2. B

    Limit the tree depth to reduce the model's effective complexity.

  3. C

    Choose settings by repeatedly checking the test score.

  4. D

    Fit preprocessing steps using the validation data.

17
Choose one
1 point

A model's training and validation performance are both poor. The model is known to be too simple, and training has converged. Which change is most appropriate?

  1. A

    Use a simpler model and increase regularization.

  2. B

    Reduce the amount of training data.

  3. C

    Try a more suitable model or add useful features.

  4. D

    Choose model settings using only the test score.

18
Written response
1 point

Name one type of curve that can help reveal overfitting or underfitting patterns.

19
Choose one
1 point

A team discovers that its training examples do not resemble the situations in which its predictions will be used. What should it prioritize to support generalization?

  1. A

    Check that the training examples are representative of the situations where predictions will be used.

  2. B

    Use only examples that are easy for the current model to predict.

  3. C

    Select training examples based on the test score.

  4. D

    Make the model more complex regardless of the data.

20
Choose one
1 point

When dividing data for model development, which practice correctly distinguishes validation data from the test set?

  1. A

    Use the test set to tune settings, then use validation data for the final evaluation.

  2. B

    Use validation data to compare models or tune settings, and reserve the test set for final evaluation.

  3. C

    Use validation data to fit the model and training data only for the final evaluation.

  4. D

    Use training data for tuning and repeatedly check the test set after every change.