Who made the decisions: Human or robot umpires? The effects of anthropomorphism on perceptions toward robot umpires

•In general, people negatively evaluated the adoption of robot umpires.•Male and younger individuals positively evaluated robot umpires.•Female and older individuals negatively evaluated robot umpires.•People created positive perceptions toward humanized robot umpires. This study examined how the adoption of robot umpires in baseball alters people’s evaluation of ball/strike decisions, the trust in umpires, game enjoyment, and their behavioral consequences. The results indicated that people perceived umpire calls as fairer and more credible, and demonstrated greater trust in human umpires than in robot umpires; however, these negative effects were attenuated when robot umpires were humanized by giving them human-like characteristics. Furthermore, the effects of robot umpires were moderated by age and gender. Younger adults and males generally had more positive perceptions toward robot umpires, while older adults and females had more positive perceptions toward humanized robot umpires.