Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
•We study the impact of peer effect on the WTP more for ecolabeled seafood products.•We estimate the determinants of willingness to pay using a Probit model.•The bid amount, the income and the peer effect positively impact willingness to pay.•We highlight on peer effect using a propensity score matching estimation.•Peer effect impacts the probability to have a positive WTP for ecolabeled products.