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classificationanalysisprojectionmathematical-optimizationnearest-neighbor

Neighbour Component Analysis implementation in Octave/Matlab


I've been trying to implement the Neighbourhood Component Analysis (NCA) algorithm in Octave, but apparently there's something wrong with my code and I cannot figure out what it is.

Note: I am using Carl Edward Rasmussen's minimize function for maximization of the negative f.

Note 2: The test data I am using is the Wine dataset available at the UCI Machine Learning repository.


Solution

  • With some external help, I've got the answer to the question. The problem was that I was assuming wrongly that vector product of the difference of datapoints i and j should be a row vector by column vector instead of the opposite: gradient