• K-nearest neighbour is based on the idea that nearby data points influence classification.

  • Case based reasoning.

  • Based on the idea that items that are located “nearby” in the data space will influence how unknown data is classified.

  • Been around since 1910.

  • Requires:

    • Distance Metric.
      • Euclidian.
      • Correlation.
      • Mahalanobis.
    • parameter (no. of neighbours).
    • Weighting Function.
    • How to combine info from neighbours.
  • Example:

    • Metric: Euclidian.
    • No weighting function.
    • Maximum vote of neighbours.

Demo can be found here