[DL輪読会]Imputing Missing Events in Continuous-Time Event Streams (ICML 2019)
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Imputing Missing Events in Continuous-Time Event
Streams (ICML 2019)
Akitoshi Kimura, Taniguchi Lab, Waseda University
2. 書誌情報
• 著者:
– Hongyuan Mei
• Department of Computer Science, Johns Hopkins University, USA
– Guanghui Qin
• Department of Physics, Peking University, China
– Jason Eisner
• Department of Computer Science, Johns Hopkins University, USA
• 学会:
– ICML 2019 Oral, Poster
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3. 概要
• イベント系列を Neural Hawkes process でモデリング
• イベント系列の観測されなかった部分の補完
– Medical records, Competitive games, User interface interactions
• 提案分布に bidirectional continuous-time LSTM を適用
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9. モデル
• 𝑝𝑝𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚: neural Hawkes process
– Intensity function:
– History:
– Hidden state vector at time t:
• 𝑝𝑝𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚: missing at random: 𝑧𝑧 に依存しない
– missing not at random: 𝑧𝑧 に依存する
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13. 損失関数
• Minimum Bayes Risk decoding, consensus decoding
– Optimal transport distance:
– The set of all alignments between 𝑧𝑧 and 𝑧𝑧∗
:
– The total cost given the alignment 𝑎𝑎:
• decomposed as
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14. 実験
• Missing data mechanisms
• Datasets
– Synthetic datasets
– Elevator system dataset
– New York city taxi dataset
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19. 参考文献
• Mei, H. and Eisner, J. The neural Hawkes process: A
neurally self-modulating multivariate point process. In
Advances in Neural Information Processing Systems
(NIPS), 2017.
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