bio | website | tx.technion.ac.il/~felixg/… |
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location | ||
age | 31 | |
visits | member for | 3 years |
seen | Mar 23 at 17:56 | |
stats | profile views | 3,241 |
Mar 16 |
asked | power laws emerging from the sandpile model |
Mar 10 |
awarded | Yearling |
Feb 25 |
comment |
When does a d.r.v. take a value very close to the mean?
@Suvrit Yes, sort of. These are the volumes of all $n \times k$ submatrices of a fixed $n \times m$ matrix. |
Feb 25 |
asked | When does a d.r.v. take a value very close to the mean? |
Feb 4 |
awarded | Notable Question |
Feb 3 |
comment |
Rank changes with matrix edits
@Turbo Yes, I think it does. |
Feb 3 |
comment |
Rank changes with matrix edits
@Turbo In that case, things are open again.... :( If you want to discuss the specific case, feel free to email me. |
Feb 3 |
comment |
Rank changes with matrix edits
@Turbo Yes, all you need is Hermitianness of $M$ and $W$. But as I said, having $\{0,1\}$ helps to perhaps pinpoint precisely which of the three cases occurs. |
Feb 3 |
comment |
Rank changes with matrix edits
@Turbo The magic works because it's a rank 1 update. It's possible to use interlacing for rank $k$ updates, but the bounds get progressively weaker, of course. The proof for rank $k$ is just an inductive application of Corollary 4.3.9 $k$ times (decompose $W$ as the sum of $k$ matrices of rank $1$). |
Feb 3 |
comment |
Rank changes with matrix edits
@Turbo It's proved in the reference I gave (the standard one on the subject). |
Feb 3 |
comment |
Rank changes with matrix edits
Btw, why the extremal-combinatorics tag? Is there an interesting application you have in mind? |
Feb 3 |
answered | Rank changes with matrix edits |
Feb 2 |
revised |
An exact fraction of a matrix
edited body |
Feb 2 |
comment |
An exact fraction of a matrix
@AllenKnutson $M$ is $A$. Fixing now, Thanks. |
Feb 2 |
asked | An exact fraction of a matrix |
Jan 21 |
asked | Column Subset Selection implementations |
Jan 9 |
comment |
Sets of spreads in graphs
@Anurag I don't have an example - I am hoping to construct one for an argument I am working on. Haemers and Tonchev say in the paper that they found five different spreads but don't say whether those spreads were pairwise disjoint. If you are interested (I thought you might be :) I'll be happy to disucss this further. |
Jan 8 |
comment |
Sets of spreads in graphs
@domotorp I think that I need Baranyai's conclusion but for other hypergraphs than the complete ones. |
Jan 7 |
revised |
Sets of spreads in graphs
added 1 character in body |
Jan 7 |
asked | Sets of spreads in graphs |