Talk:Hilbert transform/GA1

GA Review

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Reviewer: Sławomir Biały (talk · contribs) 13:21, 22 November 2011 (UTC)

Comments by User:Sławomir Biały

After a quick scan, I have the following comments, in no particular order. I will add more as I read the article more carefully. Sławomir Biały (talk) 13:21, 22 November 2011 (UTC)

• In the History section, I am concerned about the following sentence: "The early 2000s saw the development of Hilbert spectroscopy which uses Hilbert transforms to detect signatures of chemical mixtures by analyzing broad spectrum signals from gigahertz to terahertz frequency radio." This sentence seems to lack appropriate perspective and focus in the context of discussing the history Hilbert transform. It is supported by a list of primary sources, and should instead have secondary sources. If none can be found, I would delete the sentence per WP:OR/WP:WEIGHT. More classically (since the 1970's), the Hilbert transform has been used to model crack formations in thin shells. I can try to find secondary sources for this.
• The Hilbert transform in signal processing section lacks credible references (either inline or otherwise). There is a single footnote (which should be converted to a Harvard citation) that links to a PDF of a very short Rand corporation technical report written by Eric Bedrosian. This is a primary source for Bedrosian's theorem, and should be supplemented with a secondary source (like this).
• I would suggest softening the Introduction section somewhat. The limit definition should be first in my opinion, and the Cauchy principal value later. I would also suggest at least one example in this section.

Comments by User:Sodin

A few remarks (after looking through the first half):

1. "function u(t)" - perhaps indicate that it is a complex-valued function of a real variable? (or, more generally, a function on a curve)
2. "David Hilbert, who first introduced the operator in order to solve a special case of the Riemann–Hilbert problem" - this sentence is anachronistic; I would at least add "what is now called" (or better a short sentence to explain what is it about)
3. The connection to the Paley–Wiener theorem is mentioned in the lead, but does not appear anywhere else (and neither in the article on PW). (Honestly, I do not even know myself what is the connection). Either expand or erase.
4. Perhaps convert inline TEX to HTML (both appear right now)? (e.g. use û(t) in the "notation" section)
5. What was Hilbert's motivation to study the discrete H.t.?
6. The section "Relationship to F.T." (btw, should not it be "relation"?) is not very clear (except perhaps for experts in signal processing). For example, "Therefore H(u)(t) has the effect of shifting the phase of the negative frequency components of u(t) by +90° (π/2 radians)" is mathematically a tautology; if this remark is important in signal processing, please explain.— Preceding unsigned comment added by Sodin (talk • contribs) 20:31, 22 November 2011‎

What's the status of this review? Comments appear to have been addressed weeks ago. Wizardman _{Operation Big Bear} 04:21, 18 December 2011 (UTC)

It appears nothing happened as a result of this review and Hilbert transform was re-listed at WP:GAN or perhaps it was never de-listed. As a result of the re-listing I volunteered to have a look at it, and I have done so. My decision was to ask for a second opinion, specifically on the matter of citation of sources. See Talk:Hilbert transform/GA2. Dolphin (t) 04:41, 29 December 2011 (UTC)