1. Miwa, M., Gozun, B., Oyama, T.: Statistical data analyses to elucidate the causes and improve the countermeasures for preventing train accidents in Japan. Int. Trans. Oper. Res. IFORS 13(3), 229–251 (2006)
2. Oyama, T., Miwa, M.: Investigating serious train accidents and natural disaster data in Japan. Commun. Oper. Res. Oper. Res. Soc. Jpn. 53(10), 11–17 (2008) (in Japanese)
3. Anwar, S., Oyama, T.: Statistical data analysis for investigating government subsidy policy for private universities. J. High. Educ. (Springer) 55(4), 407–423 (2007). On line ISSN 1573-174X
4. Srivastava, D.C., Oyama, T.: Evaluating the emission reduction targets in UNFCCC Kyoto protocol by applying primary energy data analyses. J. Asian Public Policy 2(1), 36–56 (2009)
5. Yoshii, K., Oyama, T.: A quantitative factorial component analysis to investigate the recent changes of Japan’s weight-based food self-sufficiency ratio. Am. J. Oper. Res. 6(1), 44–60 (2016)