Free Practice Quiz Question List

5 Classification Online Quiz Questions

Use this free practice quiz with 20 questions to review 5 Classification, test your knowledge, and prepare for your next test or exam.

20 questions
01
Choose one
1 point

A model uses message features to predict whether an email is “spam” or “not spam.” Which type of machine-learning task is it?

  1. A

    Classification

  2. B

    Regression

02
Fill in the blank
1 point

In classification, a model learns from examples with known and uses features to predict labels for new examples.

03
True or false
1 point

True or false: Despite its name, logistic regression is commonly used for classification.

  1. A

    True

  2. B

    False

04
Choose all
1 point

Select all scenarios that illustrate multilabel classification.

  1. A

    An email receives exactly one label: spam or not spam.

  2. B

    A fruit is assigned exactly one label: apple, orange, or pear.

  3. C

    A photo is tagged with both “beach” and “sunset.”

  4. D

    A document is tagged with both “policy” and “finance.”

05
Choose one
1 point

Which classifier seeks a boundary that separates classes with a wide margin?

  1. A

    A K-nearest neighbors model

  2. B

    A support vector machine

  3. C

    A random forest

  4. D

    A Naive Bayes model

06
Written response
1 point

Which classifier predicts from the labels of nearby training examples, typically using a majority vote?

07
Choose all
1 point

Select all statements that accurately describe the named classifiers.

  1. A

    A decision tree makes a sequence of feature-based decisions.

  2. B

    A support vector machine seeks a wide-margin boundary.

  3. C

    A logistic regression model is used only for regression, not classification.

  4. D

    A K-nearest neighbors model predicts by following a sequence of feature tests.

08
True or false
1 point

True or false: If a multiclass model estimates probabilities for mutually exclusive classes, those estimates sum to 1.

  1. A

    True

  2. B

    False

09
Written response
1 point

Which theorem does Naive Bayes use to estimate class probabilities?

10
Fill in the blank
1 point

In binary classification, a can convert the estimated probability of the positive class into a label.

11
Choose one
1 point

Which statement correctly distinguishes a classifier’s class prediction from its probability estimates?

  1. A

    The class prediction is the estimated probability for each possible label, while probability estimates are the selected label.

  2. B

    The class prediction and probability estimates are two names for the same output.

  3. C

    The class prediction is the selected label, while probability estimates give estimated probabilities for possible labels.

  4. D

    The class prediction is always a numerical value, while probability estimates are categories.

12
Open ended
1 point

A binary classifier estimates a spam probability of 0.820.82 and a not-spam probability of 0.180.18. Explain what these estimates do and do not establish, and distinguish them from a class prediction.

13
Choose one
1 point

A team needs a classifier whose feature-based decision rules can be easy to inspect. Which method best fits that need?

  1. A

    A random forest, because it combines predictions from many decision trees

  2. B

    A decision tree, because its feature-based rules can be easy to inspect

  3. C

    A support vector machine, because kernels can represent complex boundaries

  4. D

    K-nearest neighbors, because it uses labels from nearby examples

14
Choose one
1 point

An email system uses message words and sender details to predict whether each message is spam or not spam. Which kind of task is this?

  1. A

    Classification

  2. B

    Regression

  3. C

    Clustering

  4. D

    Dimensionality reduction

15
True or false
1 point

True or false: A K-nearest neighbors classifier predicts a new example’s label using labels from nearby training examples, often by majority vote.

  1. A

    True

  2. B

    False

16
Choose one
1 point

A photo-tagging system may assign both “beach” and “sunset” to the same photo. Which classification setup does this illustrate?

  1. A

    Multiclass classification

  2. B

    Multilabel classification

  3. C

    Binary classification

  4. D

    Regression

17
Written response
1 point

A team wants to combine predictions from many decision trees to often improve accuracy and help control overfitting. Which classifier should they consider?

18
Choose one
1 point

A team needs a classifier whose sequence of feature-based rules can be inspected to understand decisions such as whether a message came from an unknown sender. Which classifier best fits this need?

  1. A

    Decision tree

  2. B

    Support vector machine

  3. C

    K-nearest neighbors

  4. D

    Naive Bayes

19
Written response
1 point

A text classifier estimates class probabilities using Bayes’ theorem and assumes that features are conditionally independent given the class. What classifier is it?

20
Choose one
1 point

A classification problem calls for a boundary with a wide margin, and the team may need a kernel to represent a more complex boundary. Which classifier is designed around this approach?

  1. A

    Logistic regression

  2. B

    Decision tree

  3. C

    Support vector machine

  4. D

    K-nearest neighbors