Synergistic Person x Situation Interaction
Behavior has often been
conceived as a function of the individual’s personality and the situation in
which the person acts (Lewin, 1936). The principles by which traits and
situations jointly shape behavior are, however, less clear. Historically,
little consensus on the relative importance of both factors has been achieved.
Whereas some scholars argued that personality traits and attitudes are fairly
unimportant for the prediction of behavior (Mischel, 1968), others came to the
opposite conclusion (Epstein & O’Brien, 1985). In an attempt to resolve the
debate between these positions, proponents of a third paradigm presented
evidence that the interaction between personality and situation may be equally
or more important than the main effects associated with these factors (Bowers,
1973). Based on findings from this research, interactionism was proposed as a
new framework that would integrate the two disciplines of psychology (Cronbach,
1957) and advance the development of more comprehensive theories (Endler &
Magnusson, 1976). Researchers were encouraged to employ mixed designs instead
of looking only at situations and personality.
The enthusiasm with which
interactionism appeared on the stage of scientific psychology cooled off
quickly. In his review of aptitude x treatment interaction research, Cronbach
(1975) concluded that most interactions reported in the literature could not be
replicated even if the same treatments and the same trait measures were used.
Schmitt (1990) came to a similar conclusion in his review of moderator research
(trait x trait interaction effects). Moreover, his analysis suggested that the
likelihood of replicating a moderator effect depended on how well it was
grounded in theory. Many interactionist and moderator studies were exploratory
and concerned primarily with how much variance could be explained by
interactions. Less effort was invested in tracing systematic patterns of
interactions and in identifying general psychological principles that may
account for these patterns (Monson, Hesley, & Chernick, 1982).
Synergistic Interaction and
Functional Equivalence
We submit that at least one
such general principle is implied by a systematic pattern of interactions, a
pattern predicted by various substantive theories and confirmed in a large
number of empirical studies. The common assumption of these theories is that
functionally equivalent person and situation factors amplify each other’s effects
on behavior (or other outcome variables such as emotion and well-being). The
widely accepted additive model does not sufficiently account for such a pattern
-- unless a multiplicative component is added. We call this multiplicative
component a synergistic interaction.
The term synergy, which is
derived from systems theory, denotes a conceptual or mathematical product of
causes, and is used in many sciences as a general model to account for
non-linear change. In biology, for example, synergy means that an overall
effect (e.g., on growth) of a set of agents or factors (e.g., hormones or
nutrition) is larger than the sum of their unique effects. Factors are
functionally equivalent if they similarly affect a given outcome variable via
the same underlying mechanism.
Substantive Examples of Synergistic
Person x Situations Interactions
Various psychological
theories predict synergistic interactions between functionally equivalent
person and situation factors. The general diathesis-stress model may serve as a
first example. This model assumes that individuals differ in their
vulnerability to strain and that situations differ in their straining impact on
individuals. According to the model, the effects of both factors on well-being
are not additive. Rather, the impact of situational strain is expected to be
larger for vulnerable individuals than for hardy individuals, a pattern that
has been confirmed empirically (Marusic & Eysenck, 2001).
State-trait emotion
theories also predict synergistic person x situation interactions. Endler
(1975, 1997) and Spielberger (1972, 1988) assumed that state anxiety is a joint
function of trait anxiety and situational threat. Both factors determine state
anxiety synergistically, not additively, so that the difference in a person’s anxiety
state between two situations that vary in threat is larger for individuals high
in trait anxiety than for individuals low in trait anxiety. Endler and his
students confirmed this prediction in several studies (Endler, 1997). Based on
the same reasoning, Ruch (1993) and Stemmler (1997) found synergistic person x
situation effects for humor and anger.
Aggression is a third
theoretical domain in which synergistic interactions have been observed. For
example, several studies have found that the effect of viewing an aggressive
versus neutral film on subsequent aggressive behavior is amplified by trait
aggression (Bushman, 1995).
Synergistic interactions
are also predicted by motivation theories. One’s motivational state is a joint
function of trait motivation and the motivational power of the situation. In
achievement contexts, both factors have been found to amplify one another
(Heckhausen, 1989). Similar findings have been reported from studies of the
justice motive and justice sensitivity. For example, in a field study by
Schmitt and Dörfel (1999), dispositional justice
sensitivity amplified the effect of unfair treatment at the workplace on
well-being and absenteeism.
Synergistic Interactions in the
Domain of Justice Attitudes
In our own research we
explored synergistic interactions in the domain of justice attitudes. Attitudes
toward justice principles were chosen because situational factors of allocation
behavior are well known (Deutsch, 1985; Törnblom, 1992), and valid attitude
measures are available. Historical, experimental, and survey studies have
identified three major allocation principles: the equality principle, the
achievement principle, and the need principle (Mikula, 1980). Which principle
an individual prefers to use depends strongly on the type of resource to be
distributed (Törnblom & Foa, 1983) and the social context (Deutsch, 1985).
Additionally, attitudes determine which principle is preferred by allocators
and how recipients react to a given distribution (e.g., Bossong, 1983).
Virtually nothing is known, however, regarding the ways in which situation
factors and attitudes interact.
We propose that
situation factors and attitudes interact synergistically. Consider achievement
and attitude toward the achievement principle as functionally equivalent
factors of allocation behavior. It follows from equity theory that individuals
who contribute more to a common good deserve a larger share of rewards than do
individuals who contribute less. What then happens if attitudes are taken into
account? According to the additive model, the situation factor (achievement)
will have the same effect at all levels of attitude. The synergistic model
predicts that achievement will make a larger difference for individuals with a positive attitude
towards the achievement principle than for individuals with a negative
attitude. Similarly, individuals with a favorable attitude toward the need
principle should be more responsive to differences in the needs of recipients
than individuals with an unfavorable attitude. Furthermore, attitude towards
equality should have the opposite effects: situational achievement or need
differences should have smaller impacts on allocation behavior for individuals
with a positive attitude than for individuals with a negative attitude. Given
the bipolar nature of attitudes, the preceding effect can be reframed into a
synergistic principle: the effect of any situational information that justifies
unequal distribution will increase with increasing negativity of a
person’s attitude toward equality of allocation. Therefore, attitude toward
equality of allocation should be a more general moderator than attitudes toward
equity and need. For this reason, we chose attitude toward equality in our
research. Our hypotheses were tested in three studies.
Schmitt, Eid, and Maes
(2003) conducted a study in which six
insurance cases were described to 80 participants. Economic status of client
(high, low) and responsibility of client for damage of the insured (high, low)
were manipulated between subjects. Participants suggested a percentage of the
total costs that they considered a fair contribution by the client. In
accordance with the synergistic model, justice attitude (person factor) and
responsibility for damage (situation factor) interacted and explained five
percent of the variance of the dependent variable. With increasing negativity
of attitude toward equality, the effect of responsibility was larger. The following
figure depicts the interaction that was obtained.
Schmitt and Sabbagh (2004) conducted two experiments to
replicate the results from the Schmitt et al. (2003) study that was just
described. Whereas in the Schmitt et al. (2003) study, participants suggested a
fair distribution of losses (financial burdens) in hypothetical
situations, participants in the first experiment that Schmitt and Sabbagh
(2004) conducted distributed rewards in real situations and acted
simultaneously as allocators and recipients. Participants in the second
experiment also had to divide a reward, but acted in the role of judges who
distributed rewards between two other persons. These changes in roles,
resources, and social contexts were designed to test the synergistic
interaction hypothesis more comprehensively than would be possible in a single
study.
In the first experiment of
the Schmitt and Sabbagh (2004) study, participants were instructed to compete with another person to solve a
computerized jigsaw-puzzle as quickly as possible. Bogus feedback was used to
manipulate relative achievement. After having learned their achievement and
their opponent’s achievement, participants were asked to divide a common reward
(tokens). Attitude toward equality was measured separately. The number of
tokens participants kept for themselves served as the dependent variable.
Results corresponded to the synergistic model: the conditional main effect of
relative achievement was larger for participants with a negative attitude
toward equality than for participants with a positive attitude. The following
figure displays the effect.
In the second experiment of the
Schmitt and Sabbagh (2004) study, participants observed as two other individuals
performed the same task that was used in the first experiment: solving a
computerized jigsaw-puzzle. The two target individuals were portrayed as
opponents who competed against each other. The targets performed unequally well,
and the participant was asked to distribute their common reward fairly between
them. Participants were guaranteed anonymity. Relative achievement (2:1, 3:1)
was varied experimentally. Attitude toward equality was measured separately as
in the first experiment. The number of tokens participants awarded the winner
served as the dependent variable. A main effect of relative achievement was
expected. More importantly, a synergistic attitude x relative achievement
interaction was predicted such that the difference in number of tokens
participants awarded to winners in the 2:1 condition compared to winners in the
3:1 would be larger for participants with a negative equality attitude than for
participants with a favorable attitude toward this allocation principle. As the
following figure shows, results were in agreement with this prediction.
Synergistic Person x Situation
Interactions as Moderators
Our most recent
research goes a step beyond person x situation interaction effects on behavior.
We argue that synergistic person x situation interactions do not only occur at
the level of factors of behavior but also at the level of moderators. We apply
this reasoning to the recent discussion on the consistency of implicit and
explicit indicators of attitudes and personality traits. More specifically, we
predict that implicit-explicit-consistency depends on a possible large number
of boundary conditions. These boundary conditions may be both, attributes of
people and attributes of situations. For example, the consistency between
implicit and explicit indicators of prejudice has been assumed to vary
depending on the person’s motivation to avoid prejudiced judgments and behavior.
We argue that this motivation is not only an attribute of the person but also a
matter of the situation. In some situations, the motivation to avoid prejudice
judgments and behaviors is more pronounced than in other situations. More
importantly, from the perspective of synergistic person x situation
interactionism, both sources of the motivation to avoid prejudiced judgments of
behavior may not only affect the implicit-explicit-consistency of prejudice
indicators additively but synergistically. In other words, we assume that
people with a strong motivation to control their prejudice will be more
sensitive than people with a weak motivation to control prejudice in situations
that activate this motivation. By contrast, in situations that do not activate
the motivation to control prejudice, individuals high and low in this
motivation will differ less in their implicit-explicit consistency. A more
detailed description of this research program and its results is available elsewhere.
References
Bossong, B. (1983). Gerechtigkeitsnormen und
angemessenes Einkommen [Justice norms and fair income]. Zeitschrift für experimentelle
und angewandte Psychologie, 30, 32-44.
Bowers, K. S. (1973). Situationism in
psychology: An analysis and a critique. Psychological Review, 80,
307-336.
Bushman,
B. J. (1995). Moderating role of trait aggressiveness in the effects of violent
media on aggression. Journal of Personality and Social Psychology, 69, 950-960
Cronbach,
L.J. (1957). The two disciplines of scientific psychology. American
Psychologist, 12, 671-684.
Cronbach,
L.J. (1975). Beyond the two disciplines of scientific psychology. American Psychologist,
30, 116-127.
Deutsch, M. (1985).
Distributive justice: A social psychological perspective.
Endler,
N. S. (1975). A person - situation interaction model for anxiety. In C. D.
Spielberger &
Endler,
N. S. (1997). Stress, anxiety, and coping: The multidimensional interaction
model. Canadian Psychology, 38, 136-153.
Epstein, S., &
O’Brien, E. (1985). The person-situation debate in historical and current
perspective. Psychological
Bulletin, 98, 513-537.
Heckhausen, H. (1989). Motivation und Handeln [Motivation and action]. Berlin: Springer.
Lewin,
K. (1936). Principles of topological psychology.
Marusic, A., & Eysenck, H. J. (2001). Synergistic
interaction of smoking and neuroticism as a risk factor in schaemic heart
disease: a case-control study. Personality and Individual Differences, 30,
47-57.
Mischel,
W. (1968). Personality and assessment.
Monson, T. C., Hesley, J. W., & Chernick, L.
(1982). Specifying when personality traits can and cannot predict behavior. An
alternative to abandoning the attempt to predict single act criteria. Journal of Personality and Social Psychology, 43,
385-399.
Ruch, W. (1993). Exhilaration and humor. In M. Lewis,
& J. M. Haviland (Eds.), The handbook of emotions (pp. 605-616). New York: Guilford Publications.
Schmitt, M. (1990). Konsistenz als
Persönlichkeitseigenschaft [Consistency as a trait].
Berlin: Springer.
Schmitt, M., & Dörfel, M.
(1999). Procedural injustice
at work, justice sensitivity, job satisfaction, and psychosomatic well-being. European Journal of Social
Psychology, 29, 443-453.
Schmitt, M., Eid, M. & Maes, J.
(2003). Synergistic person x situation interaction in distributive justice
behavior. Personality and Social Psychology Bulletin, 29, 141-147.
Schmitt,
M. & Sabbagh, C. (2004). Synergistic person x situation interaction in
distributive justice judgment and allocation behavior. Personality and
Individual Differences, 37, 359-371.
Spielberger,
C. D. (1972). Anxiety as an emotional state. In C. D. Spielberger (Ed.),
Anxiety: Current trends in theory and research. (Vol. 1, pp. 23-49).
Spielberger,
C. D. (1988). State-trait anger expression inventory. Research edition.
Stemmler, G. (1997). Selective activation of traits:
Boundary conditions for the activation of anger. Personality and Individual
Differences, 22, 213-233.
Törnblom, K. Y.
(1992). The social psychology of distributive justice. In K. Scherer (Ed.),
Justice: Interdisciplinary perspectives (pp. 175-236).
Törnblom, K. Y., & Foa, U. G. (1983). Choice of a
distribution principle: cross-cultural evidence on the effects of resources. Acta Sociologica, 26, 161-173.