Affiliations
Department of Mathematical Informatics, The University of Tokyo, Tokyo, Japan,
PRESTO, Japan Science and Technology Agency, Kawaguchi, Japan
Please follow our
guidelines for comments
and review our
competing interests policy.
Comments that do not conform to our guidelines will be promptly removed and the user account disabled.
The following must be avoided:
Remarks that could be interpreted as allegations of misconduct
The first line of the third paragraph contains an incorrect figure reference. It should read 'The three social norms are schematically shown in Fig. 4 (A),'.