Social psychology is the intermediate field between sociology (the study of society) and psychology (the study of mind and behavior). Social psychology thus explores behavior in a social setting, the interaction between the self and the group. It uses experiment and observation to explain how social and cognitive processes affect individual perception and relate people to each other. The discipline covers diverse topics including interpersonal relationships, group behavior, social cognition and social influence.
The first published study in the field was the 1898 experiment of Norm Triplet on the effect of social facilitation. The experiment showed that people would do better in the presence of others on small and routine tasks but would perform worse on new and more difficult assignments. Further study was limited until World War II, when the Nazi phenomenon fuelled extensive research on persuasion and propaganda, prejudice and aggression, conformity and obedience. The field flourished in the next decades when landmark studies were produced and ethical standards were adopted. Solomon Asch made a famous experiment on conformity, showing that people would agree with the majority stance even when it was obviously wrong. His work inspired Stanley Milgram's study on obedience to authority and Leon Festinger developed his cognitive dissonance theory. Further research has focused on motivation, processing of social information and cultural influences.
Social psychology is closely linked and overlapping with personality psychology but each gives a different perspective to issues related to the self. Psychologists focus on personality traits, the steady patterns of emotions, behavior and thoughts, which differ across individuals. Social psychologists, in turn, pay much attention to cognitions, the processes of knowing, understanding and remembering. Social psychologists study attitudes, the general evaluations of objects and activities. They are interested in how attitudes, or our likes and dislikes, shape and function and how they predict a behavior. Attitudes help us structure our experience, express out beliefs and values and assert our identity.
Social cognition is a key area of interest for social psychologists seeking answers on how we perceive and remember information about the others. We try to explain events and behavior through attribution (Fritz Heider's attribution theory), ascribing causes to internal or external, stable or unstable, and controllable or uncontrollable factors. However, distortions are identified in the attribution process such as the self-serving bias - we tend to explain our own successes with internal or personality factors but blame our mistakes on external factors such as luck and weather. Another issue of social cognition is the creation of schemas - the idealized and simplified models of the world we build as we try to capture knowledge. These mental structures are evoked automatically and can lead to false perception and memory. Stereotypes are general beliefs about a specific social group and are often linked to negative attitudes (prejudice) and negative behavior (discrimination).
Social influence is another central topic in social psychology related to attitudes and group dynamics. Social influence has three forms: conformity, compliance and obedience. Conformity is to act like the others in the group in order to be accepted or to get information that might be useful. Compliance refers to change of behavior at the request of another person and obedience is to act on command.
Social psychologists do a lot of research on how social groups function and how people associate with, perceive and think within the group. Henri Tajfel's social identity theory is an influential study suggesting that people have the inner tendency to belong to and indentify with a small group, impose distinctions with outer groups and have strong ingroup preferences. Two or more people connected by social relations share same group values but sometimes members of the group would do things they would never do alone. This is because members tend to become "deindividuated" in the group, they lose their personal identity. Another distortive effect of group behavior is group polarization, which is provoked by group discussions and results in extreme, polarized views, while groupthink usually occurs in the presence of a highly authoritative leader and can result in wrong decisions.
Social psychology has no generally-accepted theory to build upon. However, it does a lot of concrete experimental research that is applicable to everyday life and helps us understand and improve our perception and behavior. It is applicable in politics in persuading people toward certain attitudes and ideas; it is applied in law in eyewitness identification, its theories are used by human resource specialists to measure satisfaction at the workplace and its studies have contributed to understanding of health and environmental behavior.