@techreport{oai:grips.repo.nii.ac.jp:00001121,
 author = {TONE, Kaoru and TSUTSUI, Miki},
 note = {https://www.grips.ac.jp/list/facultyinfo/tone_kaoru/, In DEA we are often puzzled by the big difference in CRS and VRS scores, and by the convex production possibility set syndrome in spite of the S-shaped curve often observed in many real data. In this paper we perform a challenge to these subjects., 経済学 / Economics},
 title = {How to deal with S-shaped curve in DEA}
}