A model uses labeled examples to predict whether each new email is spam or not spam. Which type of prediction task is this?
8 Introduction to Machine Learning Online Quiz Questions
Use this free practice quiz with 20 questions to review 8 Introduction to Machine Learning, test your knowledge, and prepare for your next test or exam.
True or false: If an unsupervised clustering algorithm groups customers with similar purchasing patterns, those groups are automatically meaningful customer categories.
- A
True
- B
False
A dataset is organized with examples in rows and in columns. What term completes the statement?
A company wants to predict next month's demand using historical records. Which train-test split is most appropriate for estimating performance on future demand?
- A
Randomly mix all dates so each set has a similar number of records.
- B
Train on later dates and test on earlier dates.
- C
Train on earlier dates and test on later dates.
- D
Use the test set to select the model, then report its score as a final evaluation.
Select all correct statements about the roles of training, validation, and test data.
- A
Training data is used to fit the model.
- B
A test set should be repeatedly used to guide model choices during development.
- C
A validation set may be used to compare models or tune choices.
- D
A test set is used to fit the model parameters.
Complete the statement: A model that performs well on new examples ___.
True or false: Repeatedly checking test-set results to guide model-development decisions can make the test set less independent as a final evaluation.
- A
True
- B
False
A model is intended to predict whether a customer will renew a subscription next month. Which situation is an example of data leakage?
- A
Using a validation set to compare candidate models.
- B
Including in training a feature that reveals an outcome only recorded after the prediction must be made.
- C
Testing on records from a later time period.
- D
Using examples with known labels to train a supervised model.
In a screening task, missing a true case is especially costly. The team therefore pays particular attention to , which measures the fraction of actual positive cases detected.
Select all correct statements about regression evaluation measures.
- A
Mean squared error penalizes large errors more heavily because it averages squared errors.
- B
Mean absolute error is the square root of mean squared error.
- C
Root mean squared error is expressed in the target's units.
- D
A lower value of any regression error measure always proves the model is suitable for every practical purpose.
A classifier has 36 true positives and 4 false positives. Using precision=TP+FPTP, what is its precision as a percentage? Enter the percentage value without the percent sign.
A model fits its training examples very closely but performs poorly on a separate set of unseen examples. Which problem does this describe?
- A
Underfitting
- B
Generalization
- C
Overfitting
- D
Data leakage
How can a clustering result be evaluated when there are no known labels, and how can the evaluation change if labels are available? Explain why a numerical score alone may not be enough.
True or false: A good test-set score guarantees that a model will perform well in every real-world setting.
- A
True
- B
False
A company trains a model on emails labeled as spam or not spam and uses it to categorize new emails. Which kind of prediction task is this?
- A
Regression, because the model predicts a value from input data
- B
Classification, because the model predicts a category
- C
Clustering, because the model predicts a known label
- D
Unsupervised learning, because the model predicts a category
Which regression measure averages the absolute differences between predicted and actual values?
A clustering algorithm groups customers with similar purchasing patterns, but no target labels were provided. What can the company reasonably conclude from the result?
- A
The groups are known labels that the algorithm learned to predict
- B
The groups must correspond to meaningful customer categories
- C
The groups are patterns in the features that need interpretation
- D
The groups prove that the customers have different causes for their purchases
A screening system is used to flag people who may have a condition, and missing a true case is especially costly. Which classification measure should the team give particular attention?
- A
Precision, because it measures how many predicted positives are truly positive
- B
Recall, because it measures how many actual positive cases are detected
- C
Accuracy, because it measures the fraction of all predictions that are correct
- D
F1 score, because it measures only the cost of missed positive cases
A retailer wants to predict demand for future weeks using historical records. Which split is most appropriate for estimating performance in the intended use?
- A
Train on earlier dates and test on later dates to reflect the model’s intended use.
- B
Randomly mix all dates so the training and test sets have similar time ranges.
- C
Train on later dates and test on earlier dates.
- D
Use only the earliest dates for both training and testing.
A model predicting whether a loan will default uses a training feature that is only recorded after the default occurs. What is this problem called?