Cognitive bias in animals is a pattern of deviation in judgment, whereby inferences about other animals and situations may be affected by irrelevant information or emotional states. It is sometimes said that animals create their own "subjective social reality" from their perception of the input. In humans, for example, an optimistic or pessimistic bias might affect ones answer to the question "Is the glass half empty or half full?" Cognitive biases have been shown in a wide range of species including rats, dogs, rhesus macaques, sheep, chicks, starlings and honeybees.