FREE Data Science MCQ Question and Answers Flashcards
6 cards from real Data Science practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 FREE Data Science MCQ Question and Answers flashcards as text
What does the bias-variance tradeoff describe in machine learning?
Answer: The balance between model simplicity and model complexity
The bias-variance tradeoff describes how increasing model complexity reduces bias but increases variance, and finding the right balance minimizes total error.
Which sampling method ensures that each subgroup of a population is proportionally represented in the sample?
Answer: Stratified Sampling
Stratified sampling divides the population into homogeneous subgroups and samples proportionally from each to ensure representative coverage.
What is the main advantage of using ensemble methods like bagging and boosting?
Answer: They reduce prediction error by combining multiple models
Ensemble methods aggregate predictions from multiple models to reduce variance or bias, generally producing more accurate and robust results.
In natural language processing, what does TF-IDF stand for?
Answer: Term Frequency-Inverse Document Frequency
TF-IDF weights words by how frequently they appear in a document relative to how common they are across all documents in the corpus.
Which type of data visualization is best suited for showing the distribution of a single continuous variable?
Answer: Histogram
Histograms display the frequency distribution of continuous data by grouping values into bins and showing their counts.
What does the R-squared value indicate in a regression model?
Answer: The proportion of variance in the dependent variable explained by the model
R-squared measures the percentage of variance in the target variable that is accounted for by the independent variables in the regression model.