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1. Can Large Language Models Assess Serendipity in Recommender Systems?

Author

Tokutake, Yu and Okamoto, Kazushi

Subjects
Computer Science - Information Retrieval
Abstract

Serendipity-oriented recommender systems aim to counteract over-specialization in user preferences. However, evaluating a user's serendipitous response towards a recommended item can be challenging because of its emotional nature. In this study, we address this issue by leveraging the rich knowledge of large language models (LLMs), which can perform a variety of tasks. First, this study explored the alignment between serendipitous evaluations made by LLMs and those made by humans. In this investigation, a binary classification task was given to the LLMs to predict whether a user would find the recommended item serendipitously. The predictive performances of three LLMs on a benchmark dataset in which humans assigned the ground truth of serendipitous items were measured. The experimental findings reveal that LLM-based assessment methods did not have a very high agreement rate with human assessments. However, they performed as well as or better than the baseline methods. Further validation results indicate that the number of user rating histories provided to LLM prompts should be carefully chosen to avoid both insufficient and excessive inputs and that the output of LLMs that show high classification performance is difficult to interpret.

Published
2024

2. Hierarchical Matrix Factorization for Interpretable Collaborative Filtering

Author

Sugahara, Kai and Okamoto, Kazushi

Subjects
Computer Science - Information Retrieval
Abstract

Matrix factorization (MF) is a simple collaborative filtering technique that achieves superior recommendation accuracy by decomposing the user-item interaction matrix into user and item latent matrices. Because the model typically learns each interaction independently, it may overlook the underlying shared dependencies between users and items, resulting in less stable and interpretable recommendations. Based on these insights, we propose "Hierarchical Matrix Factorization" (HMF), which incorporates clustering concepts to capture the hierarchy, where leaf nodes and other nodes correspond to users/items and clusters, respectively. Central to our approach, called hierarchical embeddings, is the additional decomposition of the latent matrices (embeddings) into probabilistic connection matrices, which link the hierarchy, and a root cluster latent matrix. The embeddings are differentiable, allowing simultaneous learning of interactions and clustering using a single gradient descent method. Furthermore, the obtained cluster-specific interactions naturally summarize user-item interactions and provide interpretability. Experimental results on ratings and ranking predictions show that HMF outperforms existing MF methods, in particular achieving a 1.37 point improvement in RMSE for sparse interactions. Additionally, it was confirmed that the clustering integration of HMF has the potential for faster learning convergence and mitigation of overfitting compared to MF, and also provides interpretability through a cluster-centered case study.

Published
2023
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6. Worker Organization System for Collaborative Crowdsourcing

Author

Yamamoto, Ryota, Okamoto, Kazushi, Behrens, Bernd-Arno, Series Editor, Grzesik, Wit, Series Editor, Ihlenfeldt, Steffen, Series Editor, Kara, Sami, Series Editor, Ong, Soh-Khim, Series Editor, Tomiyama, Tetsuo, Series Editor, Williams, David, Series Editor, Huang, Chin-Yin, editor, Dekkers, Rob, editor, Chiu, Shun Fung, editor, Popescu, Daniela, editor, and Quezada, Luis, editor

Published
2023
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20. Smoking, drinking, sleeping habits, and other lifestyle factors and the risk of systemic lupus erythematosus in Japanese females: findings from the KYSS study

Author

Washio, Masakazu, Horiuchi, Takahiko, Kiyohara, Chikako, Kodama, Hiroko, Tada, Yoshifumi, Asami, Toyoko, Takahashi, Hiroki, Kobashi, Gen, Abe, Takashi, Tanaka, Hisato, Nogami, Norihiko, Harada, Mine, Tsukamoto, Hiroshi, Ide, Saburo, Nagasawa, Kohei, Ushiyama, Osamu, Hotokebuchi, Takao, Okamoto, Kazushi, Sakamoto, Naomasa, Sasaki, Satoshi, Miyake, Yoshihiro, Yokoyama, Tetsuji, Mori, Mitsuru, Oura, Asae, Sinomura, Yasuhisa, Suzuki, Hiromu, Yamamoto, Motohisa, Inaba, Yutaka, and Nagai, Masaki

Published
2006
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21. Contributors

Author

Abbas, Sami, primary, AbouLaila, Mahmoud, additional, Acquas, Elio, additional, Adhikary, Biplab, additional, Afzal, M., additional, Agrogiannis, George, additional, Ahmed, Selena, additional, Alao, John P., additional, Almeida, Cristina M.M., additional, Amin, A.R.M. Ruhul, additional, Andrade, J.P., additional, Aruoma, Okezie I., additional, Asaumi, Hiroshi, additional, Assunção, Marco, additional, Augustyniak, Agnieszka, additional, Babcock, George F., additional, Babich, Harvey, additional, Bahorun, Theeshan, additional, Bajerska, Joanna, additional, Baldermann, Susanne, additional, Bandyopadhyay, Sandip Kumar, additional, Banerjee, Shuvojit, additional, Basu, Arpita, additional, Bettuzzi, Saverio, additional, Bhattacharya, Udayan, additional, Bhattacharyya, Anjan, additional, Bhattacharyya, Jharna, additional, Pathy, Nirmala Bhoo, additional, Bigelow, Rebecca L., additional, Bouglé, Dominique, additional, Brighenti, Furio, additional, Bun, Sok-Siya, additional, Byun, Eui-Hong, additional, Calani, Luca, additional, Cardelli, James A., additional, Chalo, R., additional, Chan, Laura, additional, Chan B.sc., Ruth, additional, Chan, Tak Hang, additional, Chang, Hsin-Huei, additional, Chang, Kuang-Hua, additional, Chuen-Chung Chang, Raymond, additional, Charalampos, Proestos, additional, Chatterjee, Indu Bhushan, additional, Chattopadhyay, Subrata, additional, Chen, Chung-Yu, additional, Chen, Di, additional, Chen, Haixia, additional, Hong-Duo, Chen, additional, Chen, Junping, additional, Chen, Po-Chung, additional, Chen, Richie L.C., additional, Chen, Xiaoqiang, additional, Cheng, Tzong-Jih, additional, Chu, Kai On, additional, Chyu, Ming-Chien, additional, Cimpoiu, Claudia, additional, Cuzzocrea, Salvatore, additional, Das, Asankur Sekhar, additional, Das, Dolan, additional, Das, Kaushik, additional, Bruin, Eveline A. de, additional, De Mejia, Elvira, additional, Dejaegher, Bieke, additional, Delaney, Sarah, additional, Dou, Jianpeng, additional, Dou, Q. Ping, additional, Dworakowska, Dorota, additional, Eckhoff, Rachel, additional, Egawa, Tatsuro, additional, Einother, Suzanne, additional, Elango, Ramesh, additional, Elias, Riad, additional, El-Sayed, Nesrine Salah EL-Dine, additional, Feng, Lei, additional, Feng, Wan Yong, additional, Fenu, Sandro, additional, Ferreres, Federico, additional, Figueira, Maria E., additional, Fix, Lindsey N., additional, Frazier, Richard A., additional, Frezza, Michael, additional, Gao, Xing-Hua, additional, García-Viguera, Cristina, additional, Gehrke, Sarah A., additional, Geraldine, Pitchairaj, additional, Ghosh, Arunava, additional, Giesbrecht, Timo, additional, Giunta, Brian, additional, Gil, José Ignacio, additional, Gil-Izquierdo, Angel, additional, Giri, Ashok K., additional, Gleichenhagen, Maike, additional, Grant, Paul S., additional, Gyamfi, Daniel, additional, Hamada, Taku, additional, Haque, Md Abdul, additional, Hara, Yukihiro, additional, Hashimoto, Michio, additional, Hayashi, Nobuyuki, additional, Hayashi, Tstauya, additional, He, Rong-Rong, additional, Heber, David, additional, Henning, Susanne M., additional, Hirata, Yasunobu, additional, Yuen-Shan Ho, Ku, additional, Hosu, Anamaria, additional, Houghton, Jean Marie, additional, Hsiao, Hsien-Yi, additional, Hsieh, Bo-Chuan, additional, Huang, Chun-Hsiung, additional, Huang, Dejian, additional, Hiu-Ling Hung, Clara, additional, Hung, Yueh-Tzu, additional, Hwang, Daniel H., additional, Hyun-Gyun, Yuk, additional, Igarashi, Ikuo, additional, Isobe, Mitsuaki, additional, Jasienska, Grazyna, additional, Jeszka, Jan, additional, Ji, Seon Kim, additional, Jianrong, Li, additional, Jin, Heiying, additional, Jing, Yali, additional, Jinz, Heiying, additional, Jordan, Susan, additional, Jundoria, Arvin, additional, Kalinovsky, Tatiana, additional, Kamunya, S., additional, Kanno, Yoshihiko, additional, Kanrar, Bappaditya, additional, Kao, Yung-Hsi, additional, Kapetanovic, Izet M., additional, Kapiszewska, Maria, additional, Kapsokefalou, Maria, additional, Kavantzas, Nikolaos, additional, Keller, Bradley B., additional, Kerio, Lilian C., additional, Khan, Sara Anees, additional, Kim, Jong-Min, additional, Kojima-Yuasa, Akiko, additional, Kokotkiewicz, Adam, additional, Komaitis, Michael, additional, Kottur, Govindasamy, additional, Koutelidakis, Antonios E., additional, Ku, Hui-Chen, additional, Kua, Ee-Heok, additional, Kuhnert, Nikolai, additional, Kuo, Yow-Chii, additional, Kurihara, Hiroshi, additional, Kuriyama, Shinichi, additional, Lanzett, Manuella, additional, Le, Anh D., additional, Lee, Andy H., additional, Lee, Joo Young, additional, Lee, Maw-Rong, additional, Lee, Ren-Jye, additional, Lee, Seung-Cheol, additional, Lee, Viola S.Y., additional, Li, Na-Na, additional, Li, Wei, additional, Li, Yuan-Hong, additional, Liang, Yue-Rong, additional, Lin, Chih-Ming, additional, Lin, Ching-Ling, additional, Liu, Chi-Wei, additional, Liu, Hang-Seng, additional, Liu, Pengxin, additional, Longoni, Rosanna, additional, Lorenz, Mario, additional, Lu, Jian-Liang, additional, Lu, Ya-Ning, additional, Lucas, Edralin A., additional, Łuczaj, Wojciech, additional, Luczkiewicz, Maria, additional, Luximon-Ramma, Amitabye, additional, Lynch, Paul, additional, Lyons, Timothy J., additional, Ma, Xiao, additional, Maeda-Yamamoto, Mari, additional, Mahungu, Symon M., additional, Makabe, Hidefumi, additional, Mao, Jenny T., additional, Mariga, Irvine K., additional, Maritim, T., additional, Martin, Colin R., additional, Masuda, Shuichi, additional, Matsui-Yuasa, Isao, additional, Mbuthia, Stephen Karori, additional, Medina, Sonia, additional, Mehra, Aradhana, additional, Melzig, Matthias F., additional, Merklinger-Gruchala, Anna, additional, Meydani, Mohsen, additional, Miclaus, Vasile, additional, Mitra, Chandan, additional, Miyamoto, Yohei, additional, Momoi, Nobuo, additional, Mousa, S.A., additional, Mudau, Fhatuwani Nixwell, additional, Mujtaba, Taskeen, additional, Mumy, Karen L., additional, Murakami, Akira, additional, Murase, Takatoshi, additional, Murugan, Ramalingam Senthil, additional, Murugesan, Subramanian, additional, Nagai, Ryozo, additional, Nagini, Siddavaram, additional, Nagle, Christina, additional, Nakajima, Kei, additional, Neergheen-Bhujun, Vidushi, additional, Ng, Tze-Pin, additional, Ngure, Francis Muigai, additional, Niedzwiecki, Aleksandra, additional, Niu, Kaijun, additional, Nomani, M., additional, O'Brien, Peter, additional, Ogawa, Masahito, additional, Oh, Eung Seok, additional, Okamoto, Kazushi, additional, Ollivier, Evelyne, additional, Osterburg, Andrew R., additional, Otsuki, Makoto, additional, Pang, Chi Pui, additional, Pasalich, Maria, additional, Paterniti, Irene, additional, Patsouris, Efstratios, additional, Persson, Ingrid A.-L., additional, Piljac, Ante, additional, Piljac-Zegarac, Jasenka, additional, Porto, Luís Cristóvão, additional, Prendergast, Mark A., additional, Pripdeevech, Patcharee, additional, Priyamvada, Shubha, additional, Puangpraphant, Sirima, additional, Senthil Kumar, Ramasamy Shanmugasundaram, additional, M., Gregory Raner, additional, Rath, Matthias, additional, Del Rio, Daniele, additional, Rizk, Sherine M., additional, Rizzi, Federica, additional, Robinson, Randy J., additional, Rodrigues, Jorge, additional, Roomi, M. Waheed, additional, Ross, Colleen Margaret, additional, Safer, Abdel-Majeed A., additional, Saikat, Sohel, additional, Sama, Andrew E., additional, Šamec, Dunja, additional, Sameshima, Yoichi, additional, Schuck, Alyssa G., additional, Seong, Baik-Lin, additional, Sharma, Anubha, additional, Shen, Chwan-Li, additional, Sheu, Joen-Rong, additional, Shih, Li-Jane, additional, Shimamura, Yuko, additional, Shin, Dong Moon, additional, Shitandi, Anakalo A., additional, Skrzydlewska, Elżbieta, additional, Smith, Thomas J., additional, Somanah, Jhoti, additional, Song, Jae-Min, additional, Spina, Liliana, additional, Stepp, John Richard, additional, Stoicov, Calin, additional, Sun, Guang-Huan, additional, Suzuki, Jun-ichi, additional, Tachibana, Hirofumi, additional, Tan, Jun, additional, Tang, Nelson L.S., additional, Tang, Xudong, additional, Theodore, Joseph, additional, Thomas, Philip A., additional, Tobita, Kimimasa, additional, Toolsee, Naushad A., additional, Tzen, Jason T.C., additional, Uiterwaal, Cuno S.P.M., additional, Valenca, Samuel Santos, additional, van Buren, Leo, additional, Butler, Tracy R., additional, van der Pijl, Pieter C., additional, Heyden, Yvan Vander, additional, Vignes, Michel, additional, Vinci, Stefania, additional, Wachira, Francis, additional, Walden, Charlotte M., additional, Wan, Luke, additional, Wang, Chi Chiu, additional, Wang, Haichao, additional, Wang, Piwen, additional, Wanyoko, J.K., additional, Watanabe, Naoharu, additional, Weisburg, Jeffrey H., additional, Weiss, David J., additional, Weng, Jueng-Tsueng, additional, Wink, Michael, additional, Chian Wong, Adeline Ik, additional, Wongpornchai, Sugunya, additional, Woo, Jean, additional, Wozniewicz, Malgorzata, additional, Wu, Bo-Tsung, additional, Wu, Yan, additional, Xiaoqiang, Chen, additional, Yadav, Sudhir Kumar, additional, Yamada, Hiroshi, additional, Yang, Ya Ping, additional, Yang, Ziyin, additional, Chien-Chih, Yeh, additional, Yu, Hyun-Gyun, additional, Yusufi, Ahad N.K., additional, Zahreldin, Ahmad A., additional, Zhang, Hongzheng, additional, Zhang, Liang, additional, Zhang, Baohong, additional, Zhang, Bei, additional, Zhang, Chunxia, additional, Zhang, Jing-Song, additional, Zhang, Lan, additional, Zhang, Li, additional, Zhang, Qunzhou, additional, Zhang, Zheng-Zhu, additional, Zhao, Ling, additional, Zhou, Keyuan, additional, Zhou, Limin, additional, Zhu, Dalong, additional, Zhu, Shu, additional, Zimmermann, Benno F., additional, Zingg, Jean-Marc, additional, Zuckerbraun, Harriet L., additional, and Zuo, Zhong, additional

Published
2013
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24. Dietary habits and risk of ossification of the posterior longitudinal ligaments of the spine (OPLL); findings from a case-control study in Japan*

Author

Okamoto, Kazushi, Kobashi, Gen, Washio, Masakazu, Sasaki, Satoshi, Yokoyama, Tetsuji, Miyake, Yoshihiro, Sakamoto, Naomasa, Ohta, Kaori, Inaba, Yutaka, Tanaka, Heizo, and the Japan Collaborative Epidemiological Study Group for Evaluation of Ossification of the Posterior Longitudinal Ligament of the Spine (OPLL) Risk

Published
2004
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27. Subjective usefulness and 6-year mortality risks among elderly persons in Japan

Author

Okamoto, Kazushi and Tanaka, Yuko

Subjects
Aged -- Case studies, Mortality -- Case studies, Mortality -- Japan, Health, Psychology and mental health, Seniors
Abstract

Several studies have demonstrated that the loss of a sense of one's own self-worth has an influence on the health status, psychological functioning, and quality of life in the aged. We used longitudinal data from 784 elderly residents (mean age = 73 years) to examine the relationship between subjective usefulness and 6-year mortality. We hypothesized that subjective usefulness is an important indicator of quality of life among the elderly population, and subsequently of mortality. We elicited information on subjective usefulness at baseline by using a self-administered questionnaire. Results of longitudinal analyses showed that subjective usefulness may be significantly associated with self-rated health and subsequent mortality. This indicates that subjective usefulness plays an important role in enhancing survival in the elderly population.

Published
2004

29. Association between Passive Smoking from the Mother and Pediatric Crohn’s Disease: A Japanese Multicenter Study

Author

Uchiyama, Koji, primary, Haruyama, Yasuo, additional, Shiraishi, Hiromi, additional, Katahira, Kiyohiko, additional, Abukawa, Daiki, additional, Ishige, Takashi, additional, Tajiri, Hitoshi, additional, Uchida, Keiichi, additional, Uchiyama, Kan, additional, Washio, Masakazu, additional, Kobashi, Erika, additional, Maekawa, Atsuko, additional, Okamoto, Kazushi, additional, Sairenchi, Toshimi, additional, Imamura, Yuka, additional, Ohhira, Shuji, additional, Hata, Akira, additional, and Kobashi, Gen, additional

Published
2020
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43. Agreement in the responses to self-reported and proxy-reported versions of QOL-HC: a new quality-of-life scale for patients receiving home-based medical care

Author

Kamitani, Hiroko, primary, Umegaki, Hiroyuki, additional, Okamoto, Kazushi, additional, Kanda, Shigeru, additional, Asai, Atsushi, additional, Shimojima, Takuya, additional, Nomura, Hideki, additional, Hattori, Ayako, additional, Kimata, Takaya, additional, Suzuki, Yusuke, additional, Ohshima, Hiroko, additional, and Kuzuya, Masafumi, additional

Published
2018
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44. Lifestyle factors and risk of amyotrophic lateral sclerosis: a case-control study in Japan

Author

Okamoto, Kazushi, Kobashi, Gen, Washio, Masakazu, Sasaki, Satoshi, Yokoyama, Tetsuji, Miyake, Yoshihiro, Sakamoto, Naomasa, Inaba, Yutaka, Nagai, Masaki, and et.al

Abstract

PURPOSE: We examined the associations between lifestyle factors and the risk of amyotrophic lateral sclerosis (ALS) using a case-control study in Aichi Prefecture, Japan. \nMETHODS: The study comprised 183 ALS patients diagnosed by the El Escorial World Federation of Neurology criteria as well as 366 gender- and age-matched controls randomly selected from the general population with the use of the basic register of residents. Detailed information on lifestyle factors was obtained through a mailed self-administered questionnaire. The strength of association between ALS and a potential risk factor was assessed by calculating odds ratios (ORs) and 95% confidence intervals (CIs). \nRESULTS: Vigorous physical activity, self reported stress, a type A behavior pattern, and less frequent intakes of green-yellow vegetables were significantly associated with increased risk of ALS, whereas smoking and drinking habits were not. The greatest effect on risk for ALS was posed by the combination of a type A behavior pattern and less frequent intakes of green-yellow vegetables (adjusted OR, 11.2; 95% CI, 3.8 to 33.0). \nCONCLUSION: These data suggested that imbalances between excessive productions of oxidants as patient-specific factors and a diminished or missing antioxidant defense system in motor neurons may increase the risk of ALS.

Published
2009

45. FokI variant of vitamin D receptor gene and factors related to atherosclerosis associated with ossification of the posterior longitudinal ligament of the spine: a multi-hospital case-control study

Author

Kobashi, Gen, Ohta, Kaori, Washio, Masakazu, Okamoto, Kazushi, Yokoyama, Tetsuji, Miyake, Yoshihiro, Sakamoto, Naomasa, Hata, Akira, Tamashiro, Hidehiko, Inaba, Yutaka, and et.al

Abstract

STUDY DESIGN: A sex- and age-matched case-control study with genotyping of the FokI variant of the vitamin D receptor gene (VDR) was carried out. \nOBJECTIVES: To facilitate the early prediction, prevention, and treatment of ossification of the posterior longitudinal ligament (OPLL) of the spine, we analyzed the FokI variant of VDR and past body mass indexes, histories of past illness, family history, and body pliability along with lifestyle factors. \nSUMMARY OF BACKGROUND DATA: Many possible genetic and environmental risk factors for OPLL have been suggested, including male sex, high body mass index, diabetes mellitus, trauma, hormonal imbalance, and dietary and sleeping habits and genetic variants. \nMETHODS: Both a self-administered questionnaire and whole blood samples were obtained from 63 patients with OPLL and 126 sex-, age-, and hospital-matched controls free of backbone diseases were randomly selected from hospital patients. VDR genotyping was carried out using PCR-RFLP methods. After univariate analysis, multivariate and subgroup analyses according to the VDR genotype was applied to clarify the confounding relationship between VDR genotype and other possible risk factors. \nRESULTS: A multivariate analysis revealed that the VDR FF genotype, family history of myocardial infarction, high body mass index at age 40, long working hours, and working with night shift to be independent potent risk factors for OPLL. \nCONCLUSION: The risk of developing OPLL may possibly be reduced gradually and effectively by removing or minimizing the effect of such lifestyle factors one at a time through targeted preventive intervention.

Published
2008

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