Talk:Binomial inverse theorem

Woodbury
This seems to be the same as the Woodbury matrix identity. I guess these pages should be merged? -- Jitse Niesen (talk) 14:19, 28 December 2006 (UTC)


 * Absolutely. Also, this page has no citations as to where the title is from. Jmath666 06:54, 30 September 2007 (UTC)


 * Actually, it is slightly more general. But it should be merged just the same. Jmath666 07:04, 30 September 2007 (UTC)


 * How is it "slightly more general"? Just giving more details?  DavidMCEddy (talk) 17:26, 16 January 2016 (UTC)
 * I think this should be merged into the Woodbury matrix identity page, not the other way around: The Woodbury article received 12,435 views in the last 90 days, while this only received 2,493 over the same period.  Of course, we need a redirect, because I know the name "binomial inverse theorem" and not "Woodbury", and I suspect that's true for others.  (On the other hand, I can't volunteer to do the merge.)  DavidMCEddy (talk) 17:33, 16 January 2016 (UTC)
 * ✅ Klbrain (talk) 12:23, 27 January 2018 (UTC)

Incorrect passage?
I feel that this phrase must be incorrect: "If B = Iq is the identity matrix and q = 1". Should B not be an p×p matrix in order to be added to A? 128.100.76.56 (talk) 13:38, 7 December 2010 (UTC)
 * This is the same person (forgot to log in last time). Nevermind I figured it out.  That special case paragraph is not an extension of the previous special case (I had thought that we had already set and V to Ip).Kiyo.masui (talk) 13:42, 7 December 2010 (UTC)

Invertibility of B
The first formula also requires B to be invertible. See Henderson and Searle (1981) SIAM Review 23:53-60. They provide a more general formula when B is singular. 128.148.160.246 (talk) 13:50, 8 March 2012 (UTC)


 * Right--the first formula requires invertibility of [B+BVA—1UB], which equals [B(I+VA—1UB)].  The rank of the latter cannot exceed the rank of B, so it is not invertible unless B has full rank.


 * I'll put this in along with the citation given in the original post here. Loraof (talk) 17:14, 10 May 2015 (UTC)