DMC Statistical Methods & Data Mining Concepts Flashcards

What does 'standard deviation' represent in a dataset?

Answer: The measure of spread or dispersion around the mean

Standard deviation measures how spread out values are around the mean, with a higher value indicating greater variability in the dataset.

In data mining, what is 'clustering'?

Answer: Grouping similar data points together without predefined labels

Clustering is an unsupervised learning technique that discovers natural groupings of similar data points without using predefined class labels.

A confusion matrix is used to:

Answer: Evaluate the performance of a classification model

A confusion matrix displays true positives, false positives, true negatives, and false negatives to comprehensively evaluate classification model performance.

What does 'precision' measure in a classification model?

Answer: The ratio of correctly predicted positives to all predicted positives

Precision measures the proportion of predicted positive cases that are truly positive, indicating how reliable the model's positive predictions are.

Which technique is commonly used to handle imbalanced datasets in classification?

Answer: SMOTE (Synthetic Minority Over-sampling Technique)

SMOTE generates synthetic examples of the minority class to balance the dataset, improving classifier performance on underrepresented classes.

What does 'recall' (sensitivity) measure in a classification model?

Answer: The proportion of actual positives correctly identified by the model

Recall measures the proportion of actual positive cases that the model correctly identifies, also known as the true positive rate or sensitivity.