The processes through which people form impressions of others and interpret information about them.
Researchers have confirmed the conventional wisdom that first impressions are important. Studies show that first impressions are easily formed, difficult to change, and have a long-lasting influence. Rather than absorbing each piece of new information about an individual in a vacuum, it is common for people to invoke a preexisting prototype or schema based on some aspect of the person (for example, "grandmother" or "graduate student"), modifying it with specific information about the particular individual to arrive at an overall first impression. One term for this process is schema-plus-correction. It can be dangerous because it allows people to infer many things from a very limited amount of information, which partially explains why first impressions are often wrong.
If there is no special reason to think negatively about a person, one's first impression of that person will normally be positive, as people tend to give others the benefit of the doubt. However, people are especially attentive to negative factors, and if these are present, they will outweigh the positive ones in generating impressions. One reason first impressions are so indelible is that people have a tendency to interpret new information about a person in a light that will reinforce their first impression. They also tend to remember the first impression, or overall schema, better than any subsequent corrections. Thus if a person whom one thinks of as competent makes a mistake, it will tend to be overlooked and eventually forgotten, and the original impression is the one that will prevail. Conversely, one will tend to forget or undervalue good work performed by someone initially judged to be incompetent. In addition, people often treat each other in ways that tend to elicit behavior that conforms to their impressions of each other.
Besides impression formation, the other key area focused on in the study of social perception is attribution, the thought processes we employ in explaining the behavior of other people and our own as well. The most fundamental observation we make about a person's behavior is whether it is due to internal or external causes (Is the behavior determined by the person's own characteristics or by the situation in which it occurs?). We tend to base this decision on a combination of three factors. Consensus refers to whether other people exhibit similar behavior; consistency refers to whether the behavior occurs repeatedly; and distinctiveness is concerned with whether the behavior occurs in other, similar situations.
Certain cognitive biases tend to influence whether people attribute behavior to internal or external causes. When we observe the behavior of others, our knowledge of the external factors influencing that behavior is limited, which often leads us to attribute it to internal factors (a tendency known as the fundamental attribution error). However, we are aware of numerous external factors that play a role in our own behavior. This fact, combined with a natural desire to think well of ourselves, produces actor-observer bias, a tendency to attribute our own behavior (especially when inappropriate or unsuccessful) to external factors.
Zebrowitz, Leslie. Social Perception. Pacific Grove, CA: Brooks/Cole Publishing Co., 1990.