Hi guys, I am new to ML and was experimenting with kNN search algorithms.

I have very high dimensional data 1000+ dimensions. What data structure is best suited for such high dimensional data.

I can bring down the dimensions to apprix 150 using using PCA without being too lossy.

Even then I am having hard time finding techniques that work with such high dimensional data. I am not looking for Approximate NN search using LSH.

What is the best technique that can be used here, kd tree doesn’t work well with high dimensional data, would Rtree or ball tree be a better choice or something different?

  • xero786@alien.topOPB
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    10 months ago

    My dataset is about 8000 points, and the reason I am not using ANN is that I am trying to study and experiment how exact kNNs work, what can I do with them, what’s best amongst them in high dimensional space…

    • PM_ME_YOUR_BAYES@alien.topB
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      10 months ago

      SOMs are not like neural network predictors you would see around here, in the sense that they do not learn new feature spaces. It would have been the same if I suggested you to use kmeans to reduce the search space and then doing knn