Crack ML Interviews with Confidence: K-Nearest Neighbors (KNN 20 Q&A)
Last Updated on April 29, 2026 by Editorial Team
Author(s): Shahidullah Kawsar
Originally published on Towards AI.
Data Scientist & Machine Learning Interview Preparation
How to train a ML model using KNN in 5 steps:

The article provides a comprehensive overview of K-Nearest Neighbors (KNN), a popular machine learning algorithm, detailing its fundamental concepts such as similarity-based learning, distance calculations, prediction rules, and the importance of selecting an appropriate value for K. It explores key considerations like feature scaling, the implications of the lazy learning approach, and practical applications, reinforced by a series of interview questions and answers that assess knowledge of KNN, its advantages, and its challenges in high-dimensional spaces.
Read the full blog for free on Medium.
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