What parameter in KNN determines the distance metric used to find the nearest neighbors?Answer arean_neighborsmetricweightsalgorithm

Breakdown of the Problem

To determine which parameter in the K-Nearest Neighbors (KNN) algorithm is responsible for defining the distance metric used to find nearest neighbors, we need to examine the provided options: n_neighbors, metric, weights, and algorithm.

Relevant Concepts

1. n_neighbors: This parameter determines how many neighbors to consider when making a prediction. It does not affect the distance metric.
2. metric: This parameter specifies the distance metric to use, such as Euclidean, Manhattan, etc. It directly defines how the distance is calculated between data points.
3. weights: This determines how to weight the contribution of each neighbor (uniform weight for all or distance-based).
4. algorithm: This parameter defines the algorithm used to compute the nearest neighbors, like brute-force or KD tree.

Analysis and Detail

Looking into the parameters:

• The metric parameter is specifically responsible for choosing the distance metric, e.g., metric='euclidean' indicates that the Euclidean distance will be used to find neighbors.
• The other parameters influence how neighbors are selected or how many are selected, but do not define the distance metric directly.

Verify and Summarize

After reviewing each option in the context of KNN, we conclude that the metric parameter is the one that determines the distance metric used.

Final Answer

The parameter in KNN that determines the distance metric used to find the nearest neighbors is metric.