Free practice test

Data Scientist Practice Test

Check what you know about the data scientist job with 15 free questions and instant explanations.

Updated By the Career Education Institute Curriculum Team
About this practice test

15 multiple-choice questions on data scientist knowledge, safety and vocabulary. Submit to see your score and explanations, or open any question’s answer as you go. Nothing is saved or shared.

Question 1 of 15Overfitting means:
Show answer

Answer: The model learns noise. Overfit models perform poorly on new data.

Question 2 of 15SQL is used to:
Show answer

Answer: Query databases. SQL retrieves data.

Question 3 of 15Classification predicts:
Show answer

Answer: Categories. Classification predicts classes.

Question 4 of 15An A/B test compares:
Show answer

Answer: Two versions. It compares variants.

Question 5 of 15Why keep raw data unchanged?
Show answer

Answer: To restart cleaning if needed. Raw data preserves the original.

Question 6 of 15Which term matches this definition: “A collection of data.”
Show answer

Answer: Dataset. Dataset: A collection of data.

Question 7 of 15What does “Model” mean?
Show answer

Answer: A mathematical representation used to make predictions.. Model: A mathematical representation used to make predictions.

Question 8 of 15Which term matches this definition: “Fixing errors and gaps in data.”
Show answer

Answer: Data cleaning. Data cleaning: Fixing errors and gaps in data.

Question 9 of 15What does “Bias” mean?
Show answer

Answer: Systematic error in data or models.. Bias: Systematic error in data or models.

Question 10 of 15Which term matches this definition: “Testing model performance on different data splits.”
Show answer

Answer: Cross-validation. Cross-validation: Testing model performance on different data splits.

Question 11 of 15What does “Overfitting” mean?
Show answer

Answer: When a model learns noise instead of patterns.. Overfitting: When a model learns noise instead of patterns.

Question 12 of 15Which term matches this definition: “An input variable used in a model.”
Show answer

Answer: Feature. Feature: An input variable used in a model.

Question 13 of 15What does “Dashboard” mean?
Show answer

Answer: A visual display of key metrics.. Dashboard: A visual display of key metrics.

Question 14 of 15Which term matches this definition: “An experiment comparing two versions.”
Show answer

Answer: A/B test. A/B test: An experiment comparing two versions.

Question 15 of 15What does “SQL” mean?
Show answer

Answer: A language for querying databases.. SQL: A language for querying databases.

How to study

View training