The first step ofthe Top-k Selectionalgorithm in searchM3 tecktalk#164hiromu-nakamura @po3rin
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υΩϡϝϯτશͯͷείΞϦϯά͕ऴ͔ྃͯ͠ΒͦΕΒΛฒͼସ͑ΔͷϥϯΩϯά্ҐL൪·Ͱͷ݁Ռʹڵຯ͕͋Δ߹ඇޮɻͦ͜Ͱݕࡧʹ͓͚ΔLݸͷ࠷େཁૉʢ·ͨ࠷খཁૉʣΛબ͢ΔΛߟ͑Δɻ5PQLTFMFDUJPO
5PQLTFMFDUJPOೋώʔϓʹυΩϡϝϯτͱείΞΛอ͍࣋ͯ͘͜͠ͱͰ࠷ऴతͳιʔτͷίετΛεϧʔͰ͖Δɻώʔϓʹ֨ೲ͢Δ͔ࠜͷείΞ͚ͩݟΕྑ͍ɻೋώʔϓ
5PQLTFMFDUJPOࠓ·Ͱݕࡧʹώοτͨ͠શͯͷυΩϡϝϯτͷείΞΛܭࢉ͍͕ͯͨ͠ɺ࣮είΞΛܭࢉ͠ͳͯ͘ɺ͋ΔυΩϡϝϯτ͕UPQLʹೖΒͳ͍͜ͱΛ֬ఆͰ͖Δํ๏͕͋ΔɻͦΕ͕NBYTDPSFͱݺΕΔख๏Ͱ͢ɻ.BYTDPSF
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4DPSJOHλʔϜ .BY4DPSFUIF TFBSDI FOHJOF ͜ͷ࣌ͰzUIFzؚ͔͠·ͳ͍ϙεςΟϯάϦετͷείΞܭࢉແࢹͰ͖ΔɻͳͥͳΒ࠷େείΞݱࡏͷώʔϓͷࠜͷείΞΛ͑ͳ͍͔Βɻ5PQLTFMFDUJPO
4DPSJOHλʔϜ .BY4DPSFUIF TFBSDI FOHJOF ͜ͷ࣌ͰzUIFzͱzTFBSDIzؚ͔͠·ͳ͍υΩϡϝϯτͷείΞܭࢉແࢹͰ͖ΔɻͳͥͳΒ࠷େείΞݱࡏͷώʔϓͷࠜͷείΞΛ͑ͳ͍͔Βɻ5PQLTFMFDUJPO
*OUFSWBMCBTFEQSVOJOHTFBSDIFOHJOF%PDVNFOU ◾◾◾◾◾◾◾◾◾◾◾NBYNBYTDPSF ͜ͷ࣌ͰzFOHJOFz͚͔ͩ͠ग़ݱ͍ͯ͠ͳ͍υΩϡϝϯτແࢹͰ͖Δ͜ͷ࣌ͰzTFBSDIz͚͔ͩ͠ग़ݱ͍ͯ͠ͳ͍υΩϡϝϯτແࢹͰ͖ΔXBMLEPDT
*OUFSWBMCBTFEQSVOJOH࣮ફͰϙεςΟϯάϦετѹॖ͞Ε͍ͯΔͷͰϒϩοΫαΠζ͝ͱʹNBYTDPSFΛอ࣋͠ ֤ϒϩοΫͷ۠ΓͷΠϯλʔόϧʹ6QQFS#PVOE4DPSF 6#4Λܭࢉ͓ͯ͘͠ɻ͜ΕʹΑΓϒϩοΫղౚΛεΩοϓͰ͖ΔɻTFBSDIFOHJOF%PDVNFOU ◾◾◾◾◾◾◾◾◾◾NBYNBY NBY NBYNBY6#4
$PODMVTJPO5PQLTFMFDUJPOͰೋώʔϓͳͲͷσʔλߏ͕ར༻Ͱ͖ΔɻݕࡧείΞʹ͓͚Δ֤λʔϜ͕ߩݙ͢ΔNBYTDPSFࣄલʹܭࢉͰ͖ΔͷͰείΞܭࢉΛεΩοϓͰ͖Δɻ*OUFSWBMCBTFEQSVOJOHΛར༻͢Δ͜ͱͰѹॖΠϯσοΫεείΞܭࢉΛޮతʹߦ͑Δɻ-VDFOFͰߋʹൃలܥͷ8"/%ͱ͍͏ΞϧΰϦζϜ͕ಋೖ͞Ε͍ͯΔɻ
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The first step ofthe Top-k algorithmin searchM3 tecktalk#164hiromu-nakamura @po3rin