person-situation interaction

n. Person-situation (P × S) interaction refers to the process whereby enduring personal qualities are expressed in some situations but not in others in a systematic and predictable manner over time. Therefore, a person's characteristic behavior, thoughts, and emotions are reflected in the interaction between the person and the specific situation. Put slightly differently, what is stable about people's personality is the consistency with which they respond to particular situations in particular ways.

Historically, this notion has emerged in reaction to trait theories of personality. Trait theories assume that personality dispositions are stable across situations and across time. Therefore, the stability of personality is reflected in the consistency with which people behave similarly across situations. According to this view, for example, an aggressive person should, on average, behave more aggressively than a person who is not aggressive across a wide range of situations and settings. Trait psychologists examine similarity clusters in the personality trait descriptions people use in everyday language to identify the structure of personality – a method of investigation known as the psycholinguistic approach. Over the last four decades, this approach has revealed that trait terms cluster into five groups reflecting individual differences in people's tendencies toward neuroticism (e.g., emotional stability vs. instability), conscientiousness (e.g., selfcontrol vs. impulsivity), agreeableness (e.g., friendliness vs. unfriendliness), extroversion (e.g., high-energy, outgoing vs. low-energy, shy), and open-mindedness (e.g., conservative, rigid vs. cultured, open-minded). It is assumed that these traits express themselves in relatively stable behavior across situations. If person A is higher in extroversion (e.g., outgoing behavior) than person B at parties, he/she is expected to be higher than person B also in the office, when dealing with the boss, for example.

In the 1960s, however, research that examined people's behaviors across different situations found cross-situational consistency to be of relatively low magnitude. Although people did show some cross-situational consistency in their behavior, the consistency was much lower than what would be expected by laypeople's intuitions as well as by the trait models. Out of this research emerged the personality paradox: on the one hand, our intuitions say that there are stability and coherence to personality; on the other hand, the consistency of behavior across situations is not very high. The paradoxical question then is, Where is the locus of stability, consistency, and coherence in personality if not in cross-situational consistency?

It had been assumed until the late 1960s that the variability observed in people's behavior across situations reflected measurement error – random noise generated in the data by the unreliability of the methods used to measure behavior and personality. Thus, the situation was aggregated out by taking the average of people's behavior across situations to minimize this noise. Researchers who adopted the P × S perspective, however, raised the question of whether this variability could be systematic rather than random. They argued that the variability in a person's behavior across situations could be an expression of a stable underlying personality system, and there might be order in what seems to be chaos. P × S researchers refer to the variability of behavior across situations within a person as if-then profiles or situation-behavior signatures of personality: If Adam is with his elders, then he is outgoing, but with his peers then he is not. In contrast, if John is with his peers, then he is outgoing but not if he is with his elders.

Before this variability could be taken seriously as a viable expression of personality, however, it was necessary to demonstrate empirically that the profiles are stable across time. In other words, it needed to be demonstrated that Adam is more outgoing with his parents and teachers than with his friends and classmates every time he interacts with them. This issue was examined in a study of 6- to 11-year-old boys who resided in a summer camp. Their behavior was closely observed by counselors over many hours and many situations over the course of 6 weeks. The researchers identified five different kinds of “psychological” situations that happened frequently and in which boys' behavior (e.g., aggression, whining) was recorded: situations in which the child was positively approached by a peer (e.g., invitation to play), situations in which the child was negatively approached by a peer (e.g., teasing), situations in which an adult praised the child, situations in which an adult gave a warning to child, and situations in which an adult actually punished the child. Thus, these situations varied along two dimensions: whether the interaction was positive or negative in nature and whether the interaction was with a same-status peer or a higher-status adult.

The counselors' observations indicated that each child showed a distinctive if-then profile. For example, whereas one child was verbally aggressive above the average when warned by adults but lower than average when approached prosocially by peers, another one was highest in comparison to others when approached positively by a peer, but not when warned by an adult. More importantly, when boys' if-then profiles for odd-numbered days of the camp were compared to their profiles on even-numbered days, the profiles were highly correlated and similar. Thus, situationbehavior profiles were found to be stable, reflecting each child's distinctive situationbehavior signature.

Researchers also studied whether people are sensitive to information about their own if-then profiles. In one study, they observed college students' conscientious behavior over time and across situations, asking questions such as “Is their room tidy at home?” and “Do they arrive for class on time?” The students were also asked whether they perceived themselves as a person who is consistent in his or her conscientious behavior. The question of interest was, Do students who perceive themselves to be consistently conscientious do so because their conscientious behavior is consistent across situations and across time (for example, always tidy in their room and on time to class, thus, exhibiting cross-situational consistency) or because their conscientious behavior varies across situations in a consistent manner (for example, always tidy in their room but rarely arrives on time for class, thus, exhibiting if-then profile consistency)? The researchers found that it is the latter type of consistency that gave rise to people's perceptions of stability in their own personality, explaining how people may have strong intuitions about the consistency and coherence of their personality even though they do not necessarily behave very consistently across situations.

Research suggests that people are also sensitive to information about how behavior may systematically vary across situations in describing others' personality. For example, analyses of people's spontaneous descriptions of personality revealed that people use statements that identify the situations in which people exhibit a certain behavior and those in which they do not (e.g., “John is always outgoing and friendly when around his friends but never gives a smile to his teachers”). People also seem to underscore the stability of these relationships in their language by using certainty modifiers such as always, all the time, or never that communicate the consistency with which others behave in certain ways in specific situations.

Thus, in recent social-cognitive reconceptualizations of personality that draw from these findings, the building units for the structure of personality are considered to be individuals' expectancies, beliefs, emotions, goals, values, encodings, and competencies. These units are organized into a unique network of interconnections that function as an organized whole. Personality differences are thought to arise from differences in the content of the units people have (e.g., one person may expect to be rejected whereas another may expect to be accepted all the time) and in the organization or connections they have among themselves. For example for Person X, a situation that involves a potential dating partner may bring to mind the expectation that rejection is about to occur. This expectation, in turn, may activate the need and desire to leave the situation, leading to withdrawal and avoidance. In Person Y, in contrast, the same rejection expectation may activate anger and resentment, leading to hostile behavior even before rejection actually occurs. Thus, the content of available units and the organization among those units within the personality system explain differences in behavior between people.

How does such a model explain if-then profiles? Of all the beliefs, goals, values, encodings, and feelings that a person can potentially experience at any given time, only those which are activated (i.e., brought to mind) in a given situation can influence subsequent behavior. Thus, as the individual moves differently across situations, different goals, expectations, beliefs, emotions, competencies, and different relations are activated in relation to these differing psychological conditions. However, the organization of relations among these units remains relatively stable and invariant across situations. Let us take our previous example. For Person Y, situations that involve potential dating partners activate expectations of rejection, which lead to thoughts and emotions that result in aggressive behavior. For this same person, however, situations that involve same-sex friends may inhibit rejection expectations and instead elicit feelings of trust and safety. In these situations, Person Y may not be aggressive at all; in fact he/she may very well be even more friendly than other people. Thus, Person Y's personality may reflect a distinctive if-then profile: “if with opposite sex-partners, then aggressive, but if with same sex-partners, then friendly.” What remain stable, however, are the cognitive and affective mediating processes that generate these relationships: dating partner situations always activate rejection concerns, which are stably linked to aggressive behavioral scripts, whereas samesex peer situations always activate a sense of safety, which always leads to greater friendly behavior. In this sense, the person and the situation function in tandem in a dynamic system: we can draw conclusions about personality not by factoring the situation out, but precisely by factoring the situation in. – OA