21
Which statistical test is commonly used to determine if there is a significant difference between the means of two groups?
A)
Chi-squared test
B)
ANOVA
C)
t-test
D)
Regression analysis
Answer & Solution
Answer: Option
C
22
What does the term "imputation" refer to in data preprocessing?
A)
Creating new features
B)
Filling in missing values in a dataset
C)
Encoding categorical data
D)
None of the above
Answer & Solution
Answer: Option
B
23
In machine learning, what is the term for the process of selecting the most important features for a model?
A)
Data preprocessing
B)
Model evaluation
C)
Feature selection
D)
Hyperparameter tuning
Answer & Solution
Answer: Option
C
24
What is the primary purpose of the "Confusion Matrix" in the evaluation of classification models?
A)
To visualize data
B)
To build predictive models
C)
To summarize data
D)
To display the counts of true positive, true negative, false positive, and false negative predictions
Answer & Solution
Answer: Option
D
25
In data science, what is the primary goal of dimensionality reduction techniques like Principal Component Analysis (PCA)?
A)
To reduce the number of features while preserving important information
B)
To add more features to the dataset
C)
To normalize data
D)
To visualize data
Answer & Solution
Answer: Option
A
26
What does the acronym "ETL" stand for in the context of data warehousing?
A)
Encode, Tokenize, Leverage
B)
Estimate, Test, Label
C)
Explore, Train, Learn
D)
Extract, Transform, Load
Answer & Solution
Answer: Option
D
27
In the context of natural language processing (NLP), what is the term for assigning parts of speech (e.g., noun, verb) to words in a text?
A)
Text vectorization
B)
Feature scaling
C)
Part-of-speech tagging
D)
One-hot encoding
Answer & Solution
Answer: Option
C
28
What statistical technique is used to estimate a population parameter by repeatedly sampling from the population?
A)
Exploratory data analysis
B)
Bootstrap resampling
C)
Data preprocessing
D)
None of the above
Answer & Solution
Answer: Option
B
29
In machine learning, what is the primary purpose of cross-validation?
A)
To collect more data
B)
To build predictive models
C)
To assess a model's performance on unseen data by splitting the data into multiple subsets
D)
To create visualizations
Answer & Solution
Answer: Option
C
30
What is the main purpose of the K-nearest neighbors (K-NN) algorithm in machine learning?
A)
To perform regression analysis
B)
To cluster data into groups
C)
To reduce dimensionality
D)
To classify data points based on the majority class among their K nearest neighbors
Answer & Solution
Answer: Option
D
