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K-Nearest Neighbours

K-Nearest Neighbours

Data Science Concept

K-Nearest Neighbors

K-Nearest Neighbors (KNN) is a non-parametric algorithm used for both regression and classification tasks in supervised learning. In KNN, data is 'trained' with data points corresponding to their classifications. Based on these classifications, when new data points come in, they can be classified based on which group of data points they are nearest to. The 'K' in KNN refers to the number of neighbors considered to make the classification.

Key Highlights

  • KNN is a non-parametric algorithm, meaning it makes no assumptions about the underlying distribution of data.
  • It is a lazy learning algorithm, meaning it doesn't learn from the training data until a query is made.
  • KNN is simple and easy to implement, but can be computationally expensive for large datasets.


  1. Wikipedia
  2. Scikit-learn documentation
  3. Towards Data Science article

Applying KNN to Business

KNN can be utilized in business for a variety of applications, such as customer segmentation, fraud detection, and recommendation systems. For example, in customer segmentation, KNN can be used to group together customers with similar characteristics based on their purchase history or demographic information. This allows businesses to tailor their marketing strategies and offerings to specific customer groups, ultimately increasing customer satisfaction and revenue.

Another example is using KNN for fraud detection. By training the algorithm on past fraudulent transactions, it can be used to flag potential fraudulent transactions in real-time based on the similarities to past fraudulent behavior. This can help businesses prevent financial losses and protect their customers from fraudulent activity.

Overall, KNN is a versatile algorithm with various applications in business. By leveraging its ability to group together similar data points, businesses can make more informed decisions and improve their overall performance.