Correspondence Bias

We have a tendency to draw inferences between people’s actions and their personalities. This is what’s known as a “correspondence bias, or attribution error.” These biases, or errors, occur when we automatically link what we view as “bad or inappropriate behaviors, with internal personality flaws, rather than taking into consideration possible external factors, such as environmental causes, that may account for the behavior in question. For example: when the clerk at Wal-Mart doesn’t smile while she’s handing me back my change, I assume that she is not smiling because she is unfriendly and rude. When in reality, she’s not smiling because she has a headache and feels ill e.g. outside influences that are beyond her control. Overlooking
However, they also show that people do not extend that same courtesy to others, and cite a 1967 study by Jones and Harris as an example. In their study, Jones and Harris discovered that students determined if their classmates, who’d written pro- or anti-Castro speeches, were actually pro- or anti-Castro. The speakers weren’t given a choice as to which Castro opinion they would defend, and their classmates were informed of this. However knowledge that their fellow students didn’t have a choice in their speech topic did not influence their
Lack of awareness. If you do not understand the external forces at work, then you are more than likely to attach personal meaning to the behaviors in question. Example: If I do not know that a store clerk is working her first day on the job, I might assume that her obvious uneasiness is attributed to a nervous disposition, rather than to first day jitters.
2. Unrealistic expectations. We expect people to be perfect, regardless of the circumstances. Example: If I view my instructor as an expert in his or her field, then I might be prone to expect their first lecture on a subject to be as informative as the last. This unrealistic expectation of consistency may set me up for disappointment, especially if (when) the instructor has an off day. This level of disappointment may remain relatively unchanged, even after I learn about the factors that caused the instructor to deliver the bad lecture.
3. Inflated categorization. My expectations of my instructor are going to be even more flawed if I unrealistically expect all instructors to be equally knowledgeable. Also, if I believe that asking questions is proof of ignorance, I might view any question he poses to the students, as outward proof that he (instructor) does not know the answer to his own