Talk:Kronecker product

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Mathematics rating:	Start Class	Mid Priority	Field: Algebra
Please update this rating as the article progresses, or if the rating is inaccurate. Click to show/hide comments. Please add to or update the comments to suggest improvements to the article. --Cronholm144 03:31, 16 June 2007 (UTC)

[edit] Request

Requesting addition/articles for Khatri-Rao and Tracy-Singh products. [1] Shyamal 04:39, 25 July 2006 (UTC)

Y Done - actually a few months ago. -- StevenDH (talk) 20:23, 16 April 2008 (UTC)

[edit] add bases to comparison to abstract tensor product

The paragraph should note that a choice of bases is involved: If A and B represent homomorphisms given certain bases of the involved vector spaces, the Kronecker product of A and B represents the tensor product of these homomorphisms with respect to certain bases of the tensor products of the domain and codomain vector spaces of the form a_1 x b_1, a_1 x b_2, ..., a_1 x b_n, a_2 x b_1, ... 84.190.181.201

[edit] Column-wise Khatri-Rao product

An anonymous user edited (concerning the final related matrix operation):

<!-- comment: the following definition is the same as the above except that it uses implicit partitions instead of explicit partitions... is there really need for this second example? -->

The reason I got me a Wikipedia-account in the first place was that I needed the definition of the colunm-wise KR product for my master's thesis, and I was tired of always looking in the paper by Liu. Later I examined this paper in which I saw (on p.3 in the pdf) what I had by then found out namely that the Khatri-Rao product is implied to operate on matrices with as partitions their columns. I wasn't sure whether this would be a mistake or a different (and confusing) convention or something, therefore, and also for my own reference, I added it to the article as a seperate case. But maybe it needs some clarification. -- StevenDH (talk) 20:23, 16 April 2008 (UTC)

I was the anonymous user who added that. That's interesting to hear why you initially added it. As you can see, I changed the wording in the article to say that both may be called the KR product. I've used the KR product in a couple papers recently in which I just define it as implicitly partitioning columns to avoid any confusion. As it stands, I left the example you added because it probably is better to include both examples (it appears both definitions are used).24.91.117.221 (talk) 17:03, 26 May 2008 (UTC)