Final answer:
Cheng is exhibiting institutional bias, specifically alma mater bias, by showing preferential treatment to teams from his former university and being overly critical of teams from other schools.
Step-by-step explanation:
Cheng is displaying a type of bias known as alma mater bias or institutional bias, which is a form of favoritism toward something based on one's personal experiences or relationships. This bias occurs when an individual, like Cheng, shows preferential treatment towards a group or an entity because it is associated with a place the individual feels a strong connection to, in this case, his former university. By being harsher on teams that are not from Tech University, Cheng's judgments are influenced by his partiality towards his alma mater rather than evaluating all teams based on a set standard of merit.