Talk:Projection matrix

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Mathematics B‑class Mid‑priority

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This opening sentence seems weird:

The hat matrix, H, is used in statistics to relate errors in residuals to experimental errors.

I'm going to think about how to rephrase it. Michael Hardy (talk) 22:50, 12 January 2008 (UTC)[reply]

I've just done that and rewritten the article to leave the use of H in formulae to do with errors to later, and changed to more standard notation for linear models as used in other Wikipedia entries. Qwfp (talk) 15:26, 10 September 2008 (UTC)[reply]