{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T03:46:38Z","timestamp":1777693598281,"version":"3.51.4"},"reference-count":32,"publisher":"SAGE Publications","issue":"2-3","license":[{"start":{"date-parts":[[2020,10,13]],"date-time":"2020-10-13T00:00:00Z","timestamp":1602547200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["ICGA Journal: The Journal of the Computer Games Community"],"published-print":{"date-parts":[[2020,11,10]]},"abstract":"<jats:p>\n                    The idea to let machines play games like Chess is quite old, with the\n                    <jats:sc>Turk<\/jats:sc>\n                    <jats:xref ref-type=\"fn\">1<\/jats:xref>\n                    <jats:fn>\n                      <jats:label>\n                        <jats:sup>1<\/jats:sup>\n                      <\/jats:label>\n                      <jats:p>\n                        <jats:uri>https:\/\/en.wikipedia.org\/w\/index.php?title=The_Turk&amp;oldid=968314029<\/jats:uri>\n                      <\/jats:p>\n                    <\/jats:fn>\n                    being one of the first hints. With the invention of computers, this idea got a new boost, and soon the first chess programs were presented. It took about 50 years until it was clear that the machines are superior chess players, far beyond the playing strengths of any human players. In the 1970s, the era of efficient search engines started and in 2004, the chess program\n                    <jats:sc>Hydra<\/jats:sc>\n                    clearly crossed the 3000 Elo mark, ahead of all other machines and human players. In this paper, we present a review on the chess program\n                    <jats:sc>Hydra<\/jats:sc>\n                    , on a technical level as well as from a social perspective.\n                  <\/jats:p>","DOI":"10.3233\/icg-200165","type":"journal-article","created":{"date-parts":[[2020,10,13]],"date-time":"2020-10-13T12:45:30Z","timestamp":1602593130000},"page":"132-151","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":0,"title":["Hydra: Report and technical overview"],"prefix":"10.1177","volume":"42","author":[{"given":"Ulf","family":"Lorenz","sequence":"first","affiliation":[{"name":"University Siegen","place":["Germany"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christian","family":"Donninger","sequence":"additional","affiliation":[{"name":"University Siegen","place":["Germany"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Muhammad N.","family":"Ali","sequence":"additional","affiliation":[{"name":"University Siegen","place":["Germany"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Erdogan","family":"G\u00fcnes","sequence":"additional","affiliation":[{"name":"University Siegen","place":["Germany"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christopher","family":"Lutz","sequence":"additional","affiliation":[{"name":"University Siegen","place":["Germany"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"179","published-online":{"date-parts":[[2020,10,13]]},"reference":[{"key":"e_1_3_1_2_1","unstructured":"Ali M.N. & Friedel F. (2003). All about the Hydra chess project. Chess News. https:\/\/en.chessbase.com\/post\/all-about-the-hydra-che-project."},{"issue":"3","key":"e_1_3_1_3_1","first-page":"55","article-title":"Root evaluation errors: How they arise and propagate","volume":"11","author":"Alth\u00f6fer I.","year":"1988","unstructured":"Alth\u00f6fer, I. (1988). Root evaluation errors: How they arise and propagate. ICCA Journal, 11(3), 55\u201363.","journal-title":"ICCA Journal"},{"key":"e_1_3_1_4_1","doi-asserted-by":"crossref","unstructured":"Berliner H.J. (1985). HiTech wins North American Computer-Chess Championship. ICCA Journal 8(4).","DOI":"10.3233\/ICG-1985-8412"},{"key":"e_1_3_1_5_1","doi-asserted-by":"crossref","unstructured":"Bernstein A. Arbuckle T. De Roberts M.V. & Belsky M. (1958). A chess playing program for the IBM 704. 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