The following discussion is an archived debate of the proposed deletion of the article below. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review). No further edits should be made to this page.

The result was Keep -- consensus has determined that Prof. Harizanov meets Wikipedia's notability standards. Pastor Theo (talk) 11:36, 20 July 2009 (UTC)[reply]

Valentina Harizanov (edit | talk | history | protect | delete | links | watch | logs | views) (delete) – (View log)

I sent this here from prod because I am not sure whether or not her scholarly record is enough for notability. A considerable number of papers in good journals, full professor at a research university, but the work is not highly cited; h index = 5. DGG (talk) 22:25, 13 July 2009 (UTC)[reply]

• Comment. In Google Scholar, by VS-Harizanov, I see an h-index of 8. Other workers in the fields she works in, such as Bakhadyr Khoussainov, D. Hirschfeldt and Rod Downey have much higher h-indices. Although none of these guys have articles, Hirschfeldt and Downey are already mentioned in Wikipedia in various places as discoverers or as sources. Abductive (talk) 23:09, 13 July 2009 (UTC)[reply]
  • Using VS-Harizanov instead of V-Harizanov misses a few of her best-cited papers: "Enumerations in computable structure theory" with 38 citations and "Frequency computations and the cardinality theorem" with 25. That said, it doesn't change the overall numbers that much. —David Eppstein (talk) 15:59, 14 July 2009 (UTC)[reply]
• Note: This debate has been included in the list of Academics and educators-related deletion discussions. —John Z (talk) 02:59, 14 July 2009 (UTC)[reply]
• Comment. Her name comes up #1, #3, #5, and #8 in a search for computable structure theory (and similarly for computable model theory), so that's a good sign. Is it a sufficiently important area that one of its top researchers can inherit notability from it? I don't know. The same searches, by the way, show Julia F. Knight to be even more well cited in the same area, but our lack of an article on Knight should not be used against Harizanov: Knight clearly passes WP:PROF by virtue of her named chair at Notre Dame. —David Eppstein (talk) 03:39, 14 July 2009 (UTC)[reply]
  • Not the first author on the computable structure theory ones. Abductive (talk) 04:36, 14 July 2009 (UTC)[reply]
    • In math, the authors are alphabetical, so you can't infer anything from the ordering. I meant that the papers with those positions in the search were co-authored by her. —David Eppstein (talk) 04:43, 14 July 2009 (UTC)[reply]
      • Comment. To reinforce the above comment: Deducing information from the order of authors on a research paper is fraught with difficulty as conventions vary so widely (alphabetical order, reverse alphabetical order, seniority, contribution to paper, include the whole research group on any of its papers, being the boss, honorary publication, student-goes-first (even though the student may have done no more than plod through the steps of a recipe written by the supervisor and guided every step of the way, etc. etc. etc.). Reliable sources are needed for assumptions about author order but I doubt if they exist. Xxanthippe (talk) 03:03, 18 June 2009 (UTC).[reply]
        • A reliable source: "in mathematical disciplines, by convention, co-authors are listed alphabetically", DOI:10.1007/s11948-006-0054-3. —David Eppstein (talk) 06:58, 15 July 2009 (UTC)[reply]
          • An amusing source, but scarcely a reliable one! The author needs to prove that he speaks for the whole community. Unfortunately I have access to only the first page. Xxanthippe (talk) 09:55, 15 July 2009 (UTC).[reply]
      • Interesting. Does any review paper exist saying that Harizanov "pioneered", "advanced", "discovered" or similar language anything? Abductive (talk) 09:01, 14 July 2009 (UTC)[reply]
        • Hirschfeldt, " Degree Spectra of Relations on Computable Structures", Bull. Symb. Logic 6:197-212, 2000 says the degree spectrum approach "began with the work of Harizanov". There's a similar remark in a paper of Hirschfeldt and White, "Realizing Levels of the Hyperarithmetic Hierarchy as Degree Spectra of Relations on Computable Structures", J. Formal Logic 43:51-64, 2002. Downey reviews the Handbook of Computability Theory in Studio Logica 71:133-139, 2002; he writes that he prefers a survey of Harizanov to one that was included, one of the reasons being that the one in the book had the degree spectrum as a "notable omission". Is that the sort of thing you mean? —David Eppstein (talk) 15:44, 14 July 2009 (UTC)[reply]
          • Yes, that would be secondary sources attesting to her notability. Abductive (talk) 15:48, 14 July 2009 (UTC)[reply]
• Weak keep on the basis of the above discussion and her selection as plenary speaker for the 2009 European ASL meeting. I think there's some evidence that she passes WP:PROF #1. —David Eppstein (talk) 18:18, 14 July 2009 (UTC)[reply]
• Delete. The subject’s citation impact seems to be low by WP:PROF standards; so is the h-number found by Abductive. The subject’s most widely held book in libraries, Induction, algorithmic learning theory, and philosophy, is currently in less than 100 libraries worldwide according to WorldCat. The subject has a strong record, and is not a Full Professor by accident, but at this point I think the article was created too early. Looking at the subject’s wide range of activities, I would say that she has a good chance of becoming WP notable in the future (through criteria 1, 2 or 3, for example), but not yet there.--Eric Yurken (talk) 01:04, 15 July 2009 (UTC)[reply]
• Question: what kind of impact are people looking for? Her field, recursion theory, is one where number of citations tends to be low, cf. Google scholar |"turing degree"|. It seems to me that we should be evaluating the claim "In computable structure theory, she introduced the notion of degree spectra of relations on computable structures and obtained first significant results concerning uncountable, countable and finite Turing degree spectra" from the article. — Charles Stewart (talk) 10:06, 15 July 2009 (UTC)[reply]
• Keep: She's made a notable contribution to a substantial field, and so passed WP:PROF#1; the discussion in the introduction of Hirschfeldt (1999, Degree Spectra of Relations on Computable Structures) convinced me. Note that Hirschfeldt's supervisor was Richard Shore, one of the most respected recursion theorists. — Charles Stewart (talk) 10:49, 15 July 2009 (UTC)[reply]
• Neutral. I agree the field is a bit insular. As this is closely related to one of my fields of research, I feel I should know her. But I haven't kept up in the field. Just in case someone was expecting me to weigh in as an expert. If the statement "she … obtained first significant results concerning uncountable, countable and finite Turing degree spectra" can be sourced, I would agree she's notable. I'm not sure the Hirschfeldt's thesis should be given much weight; she is given credit in the abstract, which the Committee would have read and reviewed, and Shore probably qualifies as an expert per se, but it's a bit indirect. — Arthur Rubin (talk) 14:59, 15 July 2009 (UTC)[reply]

The general field in which most of her work happens, to do with computable presentations of algebras, is of obvious importance in light of the importance of algebraic structures in semantics of programming languages, and particularly in view of the criticism of the algebraic approach, that its notion of sameness for algebraic structures, isomosphism, isn't interesting because isomorphic strucrures might have no computable isomorphisms. Looking over a few papers in the literature tells me that

• The field, i.e., investigating the fine structure of computable presentations of algebras, isn't old (one source has J. B. Remmel, 1981, Recursive isomorphism types of recursive Boolean algebras, J. Symbolic Logic 46:572–594, as the first substantial investigation),
• Her contribution has been major: in her PhD she introduced the concept of "degree spectra" that seems to have been central to the field since.
• Every currently active recursion theorist I can think of has authored papers that talk about degree spectra.
• Compare |"degree spectra" algebra| (127 GS hists) to |"infinite injury"| (477 GS hits): computable algebra seems like a decent-sized part of recursion theory.

I haven't found sources that validate the claim that "she … obtained first significant results concerning uncountable, countable and finite Turing degree spectra", but that seems as much due to the fact that few works in the area seem to describe the merits of their sources or validate their work with respect to what other works say is important, Hirschfeldt being an exception. I seem to recall Stephen Simpson attacking recursion theorists for not justifying the interest of the problems— Charles Stewart (talk) 10:20, 16 July 2009 (UTC)[reply]

• Comment. Every discipline will have fields or subfields that are very specialized. If a subfield has only 10 active researchers in it, then the world authority in the field will have a very small citation impact, even though s/he will be “the” world authority. The result, in my view, is that the world authority will not meet WP:PROF criterion #1, because that criterion refers to significant impact in a “scholarly discipline”. I think “scholarly discipline” was meant, in the context of WP:PROF criterion #1, to refer to a broader area than a very specialized subfield. An analogy can be made to news topics related to science. A news topic becomes notable when it attracts broad interest, and this can come from very specialized science topics; e.g., discovery that may appear obscure at first glance, but that upon further inspection is found to have broad implications for society.--Eric Yurken (talk) 17:51, 15 July 2009 (UTC)[reply]
  • The scholarly discipline is recursion theory, which is one of the four so-called pillars of mathematical logic. You could call modern research in recursion theory very specialised, but you could say the same about set theory. Do you think that W. Hugh Woodin passes PROF#1? What measure of broad interest do you apply in making your assessment? — Charles Stewart (talk) 08:13, 17 July 2009 (UTC)[reply]
    • I think that W. Hugh Woodin has had a broader impact, and meets WP:PROF criterion #1. His citation impact is definitely higher than the subject of this AfD; it indicates notability, IMHO. While assessment notability based on Google Scholar citations is not always easy, and is contingent on the area and topic, my subjective thresholds for notability based on Google Scholar citations are 150 for the top two most widely cited publications, or 300 for the top ten. If one of these criteria is met, I generally believe the person then meets WP:PROF criterion #1, which is significant impact in a scholarly discipline.--Eric Yurken (talk) 15:56, 18 July 2009 (UTC)[reply]
      • Hah, I meet that criterion, if you count coauthored papers. I think that examination of citation metrics is a useful starting point, but talk of thresholds is very dangerous. James Munkres is very worthy of inclusion, but the 856 cites Google Scholar gives his "Topology: a first course" should not give you the idea that the text introduces new, influential ideas into mathematics. Likewise, there are many otherwise uninfluential academics who have written widely referenced survey articles. And again, key works sometimes don't get cited much, because the ideas they bring get referenced in other works: this happens particularly often with PhD thesis, which used to be hard to get: case in point, Harizanov's PhD thesis has 11 Google cites, but is the source of what appears to be her most influential idea. In short: citation analysis is a lousy substitute for understanding the impact of a scholar's ideas. Charles Stewart (talk) 20:00, 18 July 2009 (UTC)[reply]
• Keep Per Charles Stewart. If she introduced a concept "degree spectra", "central to the field" and used by "Every currently active recursion theorist .." then WP:PROF, note 2 "pioneered or developed a significant new concept" applies.John Z (talk) 22:14, 16 July 2009 (UTC)[reply]
• Weak Keep after reading the opinions of those who know the field. Xxanthippe (talk) 05:58, 17 July 2009 (UTC).[reply]
• Keep Per Charles. Paul August ☎ 16:30, 17 July 2009 (UTC)[reply]
• Keep. If one introduces a concept that becomes "central" to the field of recursion theory, one is notable. Recursion theory is the theory of computability. It explores the boundary between what computers can do and what they can't. Some might say that that is not as important as things in the interior, as opposed to the boundaries, of what is computable, such as how efficiently one can compute—a question of practical importance. But someone cited above a paper published not that long ago addressing the question of the "effective" (i.e. computable) content of mathematics, and that may be in an early stage of being understood. The fact that most mathematicians don't know what recursion theory is—it's a "specialized subfield"—has not prevented it from being important. In the present day, the concept of computability doesn't seem to be a matter of small consequence. Michael Hardy (talk) 23:40, 17 July 2009 (UTC)[reply]

The above discussion is preserved as an archive of the debate. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review). No further edits should be made to this page.