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May 25, 2023 at 8:19 comment added emonigma @seanv507 Yes, it was an XY problem, and running a regularised regression solved it. I added it as a comment to the accepted answer. Thanks!
May 25, 2023 at 8:15 vote accept emonigma
May 22, 2023 at 17:42 comment added seanv507 I think it still sounds like an XY problem. If your goal is to perform a regression with a rank deficient matrix you are better off using a regularised regression algorithm such as ridge regression (L2) or lasso (L1) coefficient regularisation. L2 is what I would naturally do for correlated - eg if NY city and NYC are 100% correlated then you will have 1/2 weight on each.
May 22, 2023 at 13:04 answer added Sycorax timeline score: 6
May 22, 2023 at 12:59 history reopened Adrian Keister
utobi
Sycorax
May 22, 2023 at 12:48 history left closed in review User1865345
whuber
Original close reason(s) were not resolved
May 22, 2023 at 8:02 history edited emonigma CC BY-SA 4.0
added 148 characters in body
May 22, 2023 at 7:07 comment added emonigma @Sycorax Fair point. I've edited the question to remove mention of dropping columns, and I believe addresses the XY problem. What I want is to invert the matrix keeping the highest possible number of dimensions.
S May 22, 2023 at 7:06 review Reopen votes
May 22, 2023 at 12:48
S May 22, 2023 at 7:06 history edited emonigma CC BY-SA 4.0
removed mention of dropping columns Added to review
May 21, 2023 at 16:43 comment added Sycorax Let me be more clear. Removing features with high correlation is, at best, only a coincidental solution to producing a full-rank matrix. At worst, it arbitrarily removes features without regard to anything you might want to learn from the model, with the kicker that it also hasn’t solved the problem of producing a full-rank matrix! In other words, this is an XY Problem. Rank-revealing factorizations like SVD or QR are examples of the tools for finding a full-rank matrix.
May 20, 2023 at 22:34 history left closed in review whuber Original close reason(s) were not resolved
S May 20, 2023 at 19:00 review Reopen votes
May 20, 2023 at 22:34
S May 20, 2023 at 19:00 history edited emonigma CC BY-SA 4.0
added explanation Added to review
May 20, 2023 at 18:54 comment added emonigma Thank you @Sycorax, I have updated the question with an explanation.
May 20, 2023 at 18:53 history edited emonigma CC BY-SA 4.0
added explanation
May 19, 2023 at 18:53 history closed Sycorax Needs details or clarity
May 19, 2023 at 18:53 history notice removed Sycorax
May 19, 2023 at 18:53 comment added Sycorax Removing pairwise correlated columns is not the same as finding a full-rank matrix, because three or more columns can have low correlation but together be collinear. (Consider the dummy variable trap.) Which goal are you trying to achieve, retaining columns with low correlation or dropping columns until your matrix is a full-rank matrix? Or something else?
May 19, 2023 at 18:21 answer added tkunk timeline score: -3
May 16, 2023 at 8:43 history notice added emonigma Draw attention
May 16, 2023 at 8:43 history edited emonigma CC BY-SA 4.0
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May 4, 2023 at 19:34 history asked emonigma CC BY-SA 4.0