A focus theory of normative conduct: Recycling
A focus theory of normative conduct: Recycling the concept
of norms to reduce littering in public places.
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This article is personal Note only, please reference
to source
Abstrak
Past research has generated
mixed support among social scientists for the utility of social norms in
accounting for human behavior. We argue that norms do have a substantial impact
on human action; however, the impact can only be properly recognized when
researchers (a) separate 2 types of norms that at times act antagonistically in
a situation—injunctive norms (what most others approve or disapprove) and
descriptive norms (what most others do)—and (b) focus Ss' attention principally
on the type of norm being studied. In 5 natural settings, focusing Ss on either
the descriptive norms or the injunctive norms regarding littering caused the
Ss' littering decisions to change only in accord with the dictates of the then
more salient type of norm.
Although social norms have a
long history within social psychology, support for the concept as a useful
explanatory and predictive device is currently quite mixed. Some researchers
have used and championed the concept as important to a proper understanding of
human social behavior (e.g., Berkowitz, 1972; Fishbein
& Ajzen, 1975; McKirnan,
1980; Pepitone,
1976; Sherif, 1936; Staub, 1972; Triandis, 1977). Others have seen
little of value in it, arguing that the concept is vague and overly general,
often contradictory, and ill-suited to empirical testing (e.g., Darley &
Latané, 1970; Krebs, 1970; Krebs & Miller, 1985; Marini, 1984). In addition, a
parallel controversy has developed within academic sociology where
ethnomethodological and constructionist critics have faulted the dominant
normative paradigm of that discipline (Garfinkel, 1967; Mehan &
Wood, 1975).
The effect of these
criticisms has been positive in pointing out problems that must be solved
before one can have confidence in the utility of normative explanations. One
such problem is definitional. Both in common parlance and academic usage, norm has more than one meaning (Shaffer, 1983). When considering
normative influence on behavior, it is crucial to discriminate between the is (descriptive) and the ought (injunctive) meaning of social norms,
because each refers to a separate source of human motivation (Deutsch & Gerard, 1955). The descriptive norm
describes what is typical or normal.
It is what most people do, and it motivates by providing evidence as to what
will likely be effective and adaptive action: “If everyone is doing it, it must
be a sensible thing to do.” Cialdini (1988) has argued that such a presumption offers an
information-processing advantage and a decisional shortcut when one is choosing
how to behave in a given situation. By simply registering what most others are
doing there and by imitating their actions, one can usually choose efficiently
and well. Researchers have repeatedly found that the perception of what most
others are doing influences subjects to behave similarly, even when the
behaviors are as morally neutral as choosing a consumer product (Venkatesan, 1966) or looking up at the
sky (Milgram, Bickman, & Berkowitz, 1969). The injunctive meaning
of norms refers to rules or beliefs as to what constitutes morally approved and
disapproved conduct. In contrast to descriptive norms, which specify what is
done, injunctive norms specify what ought to be done. That is, rather than
simply informing one's actions, these norms enjoin it through the promise of
social sanctions. Because what is approved is often what is typically done, it
is easy to confuse these two meanings of norms. However, they are conceptually
and motivationally distinct, and it is important for a proper understanding of
normative influence to keep them separate, especially in situations where both
are acting simultaneously.
A second source of
confusion surrounding the concept of social norms is that, although they are
said to characterize and guide behavior within a society, they should not be
seen as uniformly in force at all times and in all situations. That is, norms
should motivate behavior primarily when they are activated (i.e., made salient
or otherwise focused on); thus, persons who are dispositionally or temporarily
focused on normative considerations are most likely to act in norm-consistent
ways (Berkowitz, 1972; Berkowitz
& Daniels, 1964;Gruder, Romer, & Korth, 1978; Miller & Grush, 1986; Rutkowski, Gruder, & Romer, 1983; Schwartz & Fleishman, 1978). Of course, salience procedures should be effective for both
descriptive and injunctive norms. In fact, in situations with clear-cut
descriptive and injunctive norms, focusing individuals on is versus ought information should lead to behavior
change that is consistent only with the now more salient type of norm.
One purpose of this research was to test this assertion as it
applies to individuals' decisions to litter in public places. The choice of
littering behavior for this study occurred for several reasons: (a) it provides
a clearly observable action that is governed by a widely held injunctive norm (Bickman,
1972; Heberlein, 1971; Keep
America Beautiful, Inc., 1968) and
(b) it constitutes a growing social problem of considerable aesthetic,
financial, and health-related costs to the culture. In California alone, for
example, litter has increased by 24% over a recent span of 15 years, requiring
$100 million annually in cleanup costs (California Waste Management Board, 1988) and posing health threats to humans and
wildlife through water pollution, fire hazards, rodent and insect infestations,
highway accidents, and thousands of injuries suffered from discarded cans and
broken bottles (Geller, Winett, & Everett, 1982). Thus, a better understanding of the normative factors
moderating deliberate littering would be of both conceptual and practical
value.
A common
finding in the literature on littering is that the act is significantly more
likely in a littered setting than in a clean setting (e.g., Finnie, 1973; Geller, Witmer, &
Tuso, 1977; Heberlein, 1971; Krauss, Freedman, &
Whitcup, 1978; Reiter & Samuel, 1980). Although this finding is congruent with the normative view
that, in most settings, individuals tend to act in accordance with the clear
behavioral norm there (Krauss et al., 1978), it is also consistent with other motivational accounts. For
example, it might be argued that the tendency to litter more in a littered
environment is due to simple imitation. Or, it might be argued that individuals
are more likely to litter into a littered environment because they perceive
that their litter will do less damage to the state of the environment than if
it were clean.
Study 1
In our first experiment,
subjects were given the opportunity to litter into either a previously clean or
a fully littered environment after witnessing a confederate who either littered
into the environment or walked through it. By varying the state of the
environment (clean vs. littered), we sought to manipulate the perceived
descriptive norm for littering in the situation. By manipulating whether the
confederate dropped litter into the environment, we sought to affect the extent
to which subjects were drawn to focus attention on the state of the environment
and, consequently, on the relevant descriptive norm there.
We had two main
predictions: First, we expected that subjects would be more likely to litter
into an already littered environment than into a clean one. This expectation is
consistent with the findings of prior research on littering (e.g., Krauss et al., 1978; Reiter & Samuel,
1980) and
with the view that, in most settings, individuals are at least marginally aware
of the existing norms and tend to act in accordance with them. Second, and more
important, we expected the effect of the descriptive norm for littering in the
situation (as indicated by the state of the environment) to be significantly
enhanced when subjects' attention was drawn to the environment by a littering
other. This expectation was predicated on considerable prior evidence (see Fiske & Taylor,
1984, for a
review) indicating thatubstantial psychological impact can result from salience
procedures involving simple shifts in the visual prominence of stimulus
information, including normative information (Feldman, Higgins,
Karlovac, & Ruble, 1976; Ferguson & Wells,
1980; Manis, Dovalina, Avis,
& Cardoze, 1980; Ruble & Feldman,
1976; Trope & Ginnosar,
1986).
Specifically, then, we predicted an interaction such that subjects who saw the
confederate litter into a fully littered environment would litter more than
those who saw no such littering; whereas subjects who saw the confederate
litter into a clean environment would litter less than those who saw no such
littering.
Should
we obtain this interaction, we would have good support for our focus model of
normative conduct. It should be noted that the second component of this
predicted interaction adds important conceptual weight to our test in that it
is contrary to what would be anticipated by rival accounts. It is opposite to
what would be expected if subjects were motivated simply by a greater
reluctance to litter into a clean versus littered environment because of the
greater relative damage to the respective environments that such littering
would cause; by that account, subjects should be more likely to litter after
observing littering in a clean environment because the environment will have
already been damaged. Similarly, the second component of our predicted
interaction pits the norm focus/salience interpretation against a
straightforward imitation formulation, in which an unpunished litterer would be
expected to increase the littering tendencies of observers in either type of
environment. By postulating that a littering other will concentrate attention
on evidence of what the majority of people have done, thereby highlighting
normative considerations, only the (descriptive) norm focus/salience account
predicts that observed littering will reduce subsequent littering in a clean
environment.
Method
Subjects and Procedure
Norm salience
Subjects
were 139 visitors to a university-affiliated hospital who were returning to
their cars in an adjacent, multilevel parking garage during the daylight hours
of 5 days within a period of 8 consecutive days. Approximately 5 s after
emerging from an elevator, subjects encountered an experimental confederate of
college age walking toward them. In half of the instances, the confederate
appeared to be reading a large, 21.6 × 35.6 cm (81⁄2 × 14 in.) handbill, which
he or she dropped into the environment approximately 4.5 m (5 yd) before
passing the subjects (high norm salience). A second confederate judged whether
a subject had noticed the littering incident and, consequently, had deflected
his or her attention at least momentarily to the parking garage floor. The
great majority (93%) were judged to have done so, and only they were examined
as to their subsequent littering behavior. In the other half of the instances,
the confederate merely walked past the subject without carrying a handbill, so
as to provide an equivalent degree of social contact (low norm salience).
Existing descriptive norm
For some
of the subjects, the floor of the parking structure had been heavily littered
by the experimenters with an assortment of handbills, candy wrappers, cigarette
butts, and paper cups (existing prolittering norm). For the remaining subjects,
the area had been cleaned of all litter (existing antilittering norm). The
state of the environment (littered or clean) was alternated in 2-hr blocks,
with the initial state determined randomly at the start of each day. On
arriving at their cars, subjects encountered a large handbill that was tucked
under the driver's side windshield wiper so as to partially obscure vision from
the driver's seat. The handbill, identical to that dropped by the confederate,
carried a stenciled message that read, “THIS IS AUTOMOTIVE SAFETY WEEK. PLEASE
DRIVE CAREFULLY.” A similar handbill had been placed on all other cars in the
area as well.
Measure of littering
From a
hidden vantage point, an experimenter noted the driver's sex, estimated age,
and whether the driver littered the handbill. Littering was defined as
depositing the handbill in the environment outside of the vehicle. Because
there were no trash receptacles in the area, all subjects who failed to litter
did so by taking and retaining the handbill inside their vehicles before
driving away.
Analyses
Analyses
in this and subsequent studies were conducted using the SPSS-X loglinear
program, wherein tests for effects within dichotomous data are examined through
the nesting of hierarchical models. This technique allows the testing of individual
parameters by comparing the differences in the likelihood ratio chi-square of a
pair of nested models. The differenced likelihood ratio is reported as a
chi-square.
Results and Discussion
Gender
and age differences in littering have sometimes been found in past research
(see Geller et al., 1982, for a review). Therefore, before
proceeding to tests of our theoretical hypotheses, we explored the data for
gender or age differences. None were found; consequently, neither variable was
included in subsequent analyses.
Figure
1 depicts
the amount of littering that occurred in each of the four experimental
conditions. Loglinear analysis of those data produced a set of results that
conforms to that predicted by our norm focus model. First, as expected, there
was a main effect for the existing descriptive norm, in that subjects littered
more in a littered environment than in a clean environment (41% vs. 11%), χ2 (1, N = 139) = 17.06, p < .001. Second, this effect
occurred to a much greater extent under conditions of high norm salience, when
subjects' attention was drawn to the existing descriptive norm for the
environment. That is, the size of the existing descriptive-norm effect when the
confederate littered (6% vs. 54%), χ2 (1, N = 55) = 16.52, p < .001, was significantly greater
than when the confederate did not litter (14% vs. 32%), χ2 (1, N = 84) = 3.99, p < .05; the resultant interaction
was tested as a planned comparison that proved highly reliable, χ2 (1, N = 139) = 20.87, p < .001. The significant interaction
provides confirmation of our hypothesis that procedures designed to shift
attention within a setting to just one type of operative norm—in this case, the
descriptive norm—will generate behavior change that is consistent only with
that type of norm. Apparently, this is so even when the behavior in question is
governed by an injunctive norm—in this case, the antilittering norm—that is
strongly and widely held in the society (Bickman,
1972; Heberlein, 1971; Keep America Beautiful, Inc., 1968).
Percentages of subjects
littering as a function of norm salience, and the direction of the descriptive
norm regarding littering: Study 1
The pattern of results also supported the directional predictions
made from our model. That is, under conditions of high (descriptive) norm
salience, subjects littered more in a littered environment (54% vs. 32%) but
less in a clean one (6% vs. 14%), although neither simple effect was statistically
significant, χ2 s
= 2.76 and 1.18, respectively.
It is this latter finding, showing the least littering among
subjects in the high norm salience/clean environment condition, that seems the
most provocative of our study and, therefore, worthy of pursuit. After all,
from an applied standpoint, we should be principally interested in strategies
for litter abatement. Moreover, the fact that the least littering occurred
among subjects who observed prior littering into a clean environment is of
considerable conceptual interest, as it supports norm focus predictions over
those that spring from a straightforward imitation or environmental damage
account. Good reason exists, however, for caution in drawing strong conceptual
conclusions from this finding. Although part of a theoretically predicted,
significant interaction, the drop in littering due to high norm salience in the
clean environment was far from significant by itself. Of course, this lack of
significance might well have occurred because of a floor effect, owing to the
low level of littering (14%) in the low norm salience/clean environment
condition; nonetheless, in the interest of enhanced statistical confidence, a
replication seemed warranted.
Study
2
In planning to replicate and extend our initial study, we
recognized a pair of testable implications that flowed from our earlier
analysis. First, consistent with the outcomes of Study 1, a subject who
witnessed evidence of littering in an otherwise clean environment should litter
less as a result; however, the evidence would not have to take the form, as it
did in Study 1, of observed littering action. That is, the consequence of such
action—a single piece of litter lying in an otherwise clean environment—should
have the same effect, because of its conspicuousness, by drawing attention to
an environment whose descriptive norm (except for one aberrant litterer) was
clearly antilitter. Second, as the amount of litter increases progressively in
a setting, so should the likelihood that a subject will litter into it because,
by definition, that litter will change the descriptive norm for the setting.
The upshot of this pair of implications of our normative analysis is a
nonintuitive prediction: The likelihood that an individual will litter into an
environment bearing various pieces of perceptible, extant litter will be
described by a check-mark-shaped function. Little littering should occur in a
clean environment; still less should occur with a sole piece of litter in an
otherwise clean environment, but progressively greater littering should occur
as litter accumulates and the descriptive norm for the situation changes from
antilitter to prolitter.
Method
Subjects
and Procedure
Subjects were 358 visitors to an amusement park in a large
southwestern city during the evening hours of a pair of weekends in early
summer. Immediately before turning a particular corner on a park walkway,
subjects encountered a college-age experimental confederate passing out
handbills that read “DON'T MISS TONIGHT'S SHOW,” which referred to an
entertainment program sponsored by the park on weekend nights. The confederate
was instructed to give a handbill, at 1-min intervals, to the first passing
adult walking alone or to one adult (the physically closest) in the first
passing group. On turning the walkway corner, subjects, who were no longer
visible to the confederate, faced a path of approximately 55 m (60 yd) from
which no exit was possible except at its ends.
State
of the environment
All litter had been removed from the path except for varying
numbers of handbills of the sort that subjects had just been given by a
confederate. Depending on the experimental condition, the path contained 0, 1,
2, 4, 8, or 16 handbills that were visible from the path entrance.
Measurement
of littering
Because no litter receptacles were available on the path, a
subject who deposited a handbill into the environment at any point along the
path's length was considered a litterer. Subjects' littering behavior was
covertly observed by a hidden, second experimental confederate, who also timed
subjects' latency to litter (failure to litter was given a score of 100 s) and
who removed any newly littered handbills from the path. On exiting the path,
subjects turned a corner to find a pair of previously unseen litter
receptacles; virtually all subjects who had not littered to that point dropped
their handbills into one of the receptacles.
Results
and Discussion
As in Study 1, we first examined the littering data for age and
gender differences. No significant effects were obtained because of subject
age. However, we did find a significant tendency for men to litter more
frequently than women (31% vs. 19%), χ2 (1, N = 358) = 7.41, p < .01.
Figure 2 depicts the percentage of
litterers in each of the experimental conditions of Study 2. The data pattern
closely reflects the predicted checkmark shape of our normative analysis. The
checkmark function hypothesis was tested in a twostep process. First, we
constructed a planned comparison using trend weights that modeled the checkmark
shape (−2, −4, −1, 1, 2, 4). It proved significant, χ2 (1, N = 358) = 21.80, p < .01. A second planned comparison
was then performed to test whether a difference in littering occurred between
the zero littering condition and the one-piece-of-environmental-litter
condition. No significant difference was found, χ2 (1, N = 229) = 1.64, p < .20. Comparable analyses were
conducted on the latency to litter data shown inFigure 3. As with frequency to
litter, the first contrast proved significant, F(1, 352) = 20.65, p < .01, whereas the second did not (F < 1). There was no significant
interaction between any of these contrasts and gender.
Study
3
Even though the general form of the findings of Study 2 confirmed
our predictions, one crucial feature of the results offered only ambiguous support.
The hypothesized decline in littering from the clean environment condition to
the one-piece-of-litter condition of the study, although present (18% vs. 10%),
was not conventionally significant, allowing the possibility that it may have
been the overall linearity of the checkmark pattern, rather than its elbow-like
bend, that accounted for the significance of our general planned comparison.
This ambiguity is especially frustrating because, as in Study 1, it appears
that a floor effect in the data may have prevented a clear demonstration of
reduced littering under the circumstances predicted by our formulation. It is
difficult to generate significantly less littering than that of a clean
environment when the clean environment generates so little littering itself.
Consequently, we decided to conduct a conceptual replication of
the theoretically relevant conditions of Study 2 that was designed to overcome
the floor-effect problem. One way to deal with a floor effect of the sort that
faced us is to increase the statistical power associated with our significance
tests by increasing the number of subjects run in each condition. Thus, we used
an experimental setting that would allow us to record the littering decisions
of large numbers of subjects in a relatively short period of time.
Additionally, in an attempt to sharpen the impact of our single-piece-of-litter
manipulation, we chose a more conspicuous single piece of litter than we had
used in Study 2.
Specifically, subjects were college dormitory residents who found
a public service flier in their mailboxes. The environment in front of the
mailboxes had been arranged so that it contained (a) no litter, (b) one piece
of highly conspicuous litter (a hollowed-out, end piece of watermelon rind), or
(c) a large array of various types of litter, including the watermelon rind.
The dependent variable was subjects' tendencies to litter with the fliers. On
the basis of our normative analysis and the pattern of results of Studies 1 and
2, we made a pair of predictions. First, we anticipated that subjects would
litter more into a fully littered environment than into a clean one. Second, we
expected that they would litter least into an otherwise clean environment that
contained a single, attention-focusing piece of litter.
Method
Subjects
Subjects were 484 residents of a densely populated, high-rise
women's dormitory on the campus of a large state university.
Procedure
The residents' mailboxes were located in rows at one corner of the
dormitory's main lobby. The mailbox area was cut off visually from most of the
lobby by a translucent partition. Once past the partition, subjects encountered
an open area that fronted the mailboxes. During a 10 a.m. to 4 p.m. schoolday
period, residents who opened their mailboxes to find a public service flier
placed there as part of the experiment were counted as subjects, provided that
no one else was simultaneously in the area getting her mail.
Depending on the experimental condition, subjects passing through
the open area in front of their mailboxes encountered an environment that
contained no litter or a single piece of litter (a hollowed-out, heel section
of watermelon rind), or a large number of pieces of litter of various kinds
(e.g., discarded fliers, cigarette butts, paper cups, candy wrappers, and soft
drink cans), including the watermelon rind. A subject was considered to have
littered if she deposited the flier anywhere in the environment (all waste
containers had been removed) before exiting the lobby onto an elevator or through
a set of doors leading to the campus. Of those subjects who littered, the great
majority were observed by an unobtrusively placed experimenter to do so in the
area in front of the mailboxes.
Results
and Discussion
The percentages of littering in the three experimental conditions
are presented in Figure 4. Their pattern accords
well with predictions based on our normative perspective; indeed, the expected
quadratic trend was highly significant, χ2 (1, N = 484) = 23.12, p < .001. Moreover, planned contrast
tests of our two experimental predictions were supportive at conventional
levels of significance. First, subjects were more likely to litter into a fully
littered environment than into an unlittered one (26.7% vs. 10.7%), χ2 (1, N = 291) = 12.62, p < .001. Second, subjects were less
likely to litter into an environment when it contained a single, salient piece
of litter than when it was unlittered (3.6% vs. 10.7%), χ2 (1, N = 335) = 6.79, p < .01.
Percentages of subjects
littering as a function of the amount of litter in the environment: Study 3
Theoretical
Implications
To this point, we have reported data from three experiments in
three different natural settings that seem to converge sufficiently to allow
the generation of statements about the conceptual and pragmatic value of those
data. On the conceptual side, it appears that norms can be influential in
directing human action; however, in keeping with the spirit of prior criticism
of normative explanations, it is necessary for norm theorists to be specific
about both the type of norm (injunctive or descriptive) thought to be acting in
a situation and about the conditions under which it is likely to act.
Distinguishing between injunctive and descriptive norms is crucial, because
both types can exist simultaneously in a setting and can have either congruent
or contradictory implications for behavior. For example, in Study 1 we showed
that through procedures designed to highlight differing descriptive norms, we
could enhance or undermine compliance with the societywide injunctive norm
against littering. Such a finding should not be interpreted to mean that
descriptive norms are, in this instance or in general, more powerful than
injunctive norms. Rather, it is the differential focusing of attention on one
or the other sort of norm that is the key. Indeed, even within the same type of
norm, it seems to be the case from our findings that focus of attention is an
important component. In all three experiments, exposing subjects to a single
piece of litter in an otherwise clean environment–a procedure designed to draw
subjects' attention to what most people had done in the setting (i.e., the
descriptive norm)—reduced littering there.
Practical
Applications
Because littering is a social problem, it is appropriate to
consider the potential practical applications of our data as well. The finding
of greatest applied value appears to be that subjects in three different
settings littered least after encountering a single piece of litter in an
otherwise unlittered place. At first glance, such a result might seem to
suggest that individuals seeking to retard the accumulation of litter in a
particular environment might affix a single, prominent piece of litter there.
On closer consideration, however, it becomes clear that such an approach would
be inferior to beginning with a totally clean environment. Examination of Figures 2 and3, showing the average
likelihood and latency of littering among subjects in our amusement park study,
illustrates the point. Subjects who encountered a perfectly clean environment
tended not to litter there, resulting in long delays before anyone despoiled it
with a handbill. Once a single handbill appeared in the setting, subjects were even
less likely to litter, generating even longer latencies before the second piece
of litter appeared. At that point, with two pieces of litter visible in the
environment, the descriptive norm began to change, and subjects' reluctance to
litter into the setting began to deteriorate steadily, leading to shorter and
shorter littering latencies with increasing accumulations of litter. Anyone
wishing to preserve the state of a specific environment, then, should begin
with a clean setting so as to delay for the greatest time the appearance of two
pieces of litter there, because those two pieces of litter are likely to begin
a slippery-slope effect that leads to a fully littered environment and to a
fully realized perception that “everybody litters here.” This logic further
suggests that environments will best be able to retard littering if they are
subjected to frequent and thorough litter pickups that return them to the
optimal litter-free condition.
In considering the practical implications of our data, we recognized
a weakness in our decision to focus subjects' attention on the descriptive
rather than injunctive norm for littering: Procedures that focus subjects on
the descriptive norm will only reduce littering when the environment is wholly
or virtually unspoiled. Indeed, as was suggested in the data of Study 1, a
descriptive norm focus when the environment is substantially littered will tend
to increase littering there—hardly a desirable outcome for any but
theory-testing purposes. A descriptive norm-focusing procedure, then, should
only have socially beneficial effects in environments that do not need much
help. The circumstances are different, however, when the injunctive norm is
made salient and when, consequently, individuals are focused on what people typically
approve and disapprove rather than on what they typically do in a situation. By
making the injunctive norm against littering more prominent, we should expect
reduced littering even in a heavily littered environment.
A test of this hypothesis seemed instrumental to a pair of
potentially valuable goals. First, on the practical level, it might establish
norm focus procedures that could be used for litter abatement in a variety of
environments. Second, on the conceptual level, it would generate evidence for
or against our contention that focusing attention on either is or ought information will lead to behavior
change that is consistent only with the now more salient type of norm; to this
point in the research program, we had examined only half of that contention by
concentrating just on descriptive norms.
Study
4
Recall that in Study 1, we argued that a confederate's act of
dropping a flier into the environment would draw subjects' attention to that
environment and to clear evidence (that we had manipulated) concerning whether
people typically littered there. In this way, we sought to manipulate focus of
attention to the existing descriptive norm regarding littering in the setting.
Presumably, if instead the environment were to give clear evidence of what is
societally approved or disapproved there, the same attention-focusing device
would function as an injunctive norm activator, because societally based
approval or disapproval is the distinguishing characteristic of injunctive
norms (Birnbaum
& Sagarin, 1976; Marini,
1984; Sherif & Sherif, 1969).
The question of what
clear approval/disapproval cue could be placed effectively in a natural
environment to test our formulation was answered serendipitously while
conducting Study 1. That study was run in a parking garage whose walls rose
only halfway from the floor to the roof at each level. On one especially windy
day, the litter we had distributed all around the garage floor in the fully
littered environment condition was blown against an inside wall, as if someone
had swept it there in a neat line. When a confederate dropped a handbill into
that environment, virtually no subjects littered, whereas, on previous days the
majority of subjects in that experimental condition had littered. In the course
of puzzling over the discrepancy, we realized that the littering tendency of
windy-day subjects may have declined when attention was called to the
considerable litter in the environment because that litter gave the (mistaken)
impression of having been swept—a clear disapproval cue.
Armed with this potential
insight, we decided to conduct a partial replication and extension of Study 1,
in which subjects saw a confederate who either did or did not drop a handbill
into an environment that contained a large amount of either swept or unswept
litter. In the case of unswept litter, we expected to replicate the data
pattern of Study 1 for the comparable experimental cells; that is, we
anticipated that by dropping a handbill, the confederate would focus subjects'
attention on the environment and its evidence that people typically litter
there, which should cause littering to increase. By dropping a handbill into a
setting where prior litter had been swept (into piles), we anticipated that the
confederate would once again focus subjects' attention on the environment. But
in this instance, subjects would encounter a mixed message, composed of a
descriptive norm cue (abundant litter) that would incline them toward littering
and an injunctive norm cue (swept litter) that would incline them against it.
Accordingly, we predicted that the difference in littering found in the unswept
conditions would be reversed or at least reduced. Statistically, then, we
expected an interaction between our two independent variables of whether a
confederate dropped a handbill into the environment (high or low norm salience)
and whether the environment contained swept or unswept litter (presence or
absence of an injunctive norm cue). Furthermore, we expected a specific form
for that interaction, such that any difference in littering found between the
swept and unswept litter conditions under low-norm salience procedures would be
significantly enhanced under high-norm salience procedures. That is, it was our
belief that, under the low salience conditions, the normative forces present
would be registered only minimally by subjects, resulting in only a minimal
swept/unswept difference. However, under high salience conditions with normative
issues now focal, the effect would be magnified.
Method
Subjects and Procedure
Norm salience
Subjects were 127
visitors to a university-affiliated hospital during the late afternoon and
early evening hours of 6 days within a 13-day period. They underwent the same
norm salience procedures as subjects in Study 1. That is, after emerging from a
parking garage elevator, they encountered a college-age confederate who either
dropped a distinctively colored handbill onto the floor in subjects' view or simply
walked past without carrying a handbill.
Presence of an injunctive norm cue
For some subjects, the
floor of the parking structure had been heavily littered by the experimenters,
with the litter distributed across the environment in a fashion identical to
that of Study 1. For the remaining subjects, all of this ambient litter had
been swept into three large piles situated approximately 9 m (10 yd) apart in a
line. In the high-norm salience/swept litter condition, the confederate dropped
a handbill onto the floor approximately 1.5 m (5 ft) after passing the piles of
litter. It was decided to have the confederate drop the handbill immediately in
front, but in full view, of the litter piles to avoid an imitation explanation
for our predicted effect. That is, if subjects had seen the confederate drop a
handbill into one of the piles, then the predicted reduction in subjects'
subsequent littering could be interpreted as simple modeling of a decision not
to litter. The swept or unswept litter conditions were run in alternating 2-hr
blocks, with the first run of the day determined randomly.
Measure of littering
Littering was assessed as
it was in Study 1.
Results and Discussion
The influence of age and
gender on littering rates was examined in an initial analysis; no significant
effects occurred. Thus, these variables were not included in further analyses.
The percentage of
subjects who littered in each of the experimental conditions of our design is
displayed in Figure
5.
Those percentages occurred in a pattern consistent with the form of the
interaction that we were led to anticipate from our norm focus formulation.
Using loglinear analyses, we tested that interaction with a planned comparison
that contrasted the difference between the two low-norm salience cells (29% vs.
33%), χ2 (1, N = 68) = 0.18, ns, aginst the difference between the two
high-norm salience cells (18% vs. 45%), χ2 (1,N = 59) = 5.19, p < .02. That interaction test proved
significant, χ2 (1, N = 127) = 4.91, p < .03.
Percentages of subjects littering as a function of norm salience,
and the configuration of litter in the environment: Study 4
Looking at the
interaction pattern in another way, we can see that it is composed of two
opposing trends-neither significant by itself, but significantly different in
contrast to one another—both instigated by the same attention-focusing
procedure. That is, when a dropped handbill drew attention to an unswept
environment that, by its fully littered nature, gave evidence of a clear
descriptive norm favoring littering there, littering tendencies rose (33% vs.
45%). However, when the same device drew attention to an environment that included
a clearly conflicting injunctive norm cue as well, littering tendencies were
reversed (29% vs. 18%). This pattern of effects accords well with each of the
goals we set for Study 4. First, it supports our theoretical assertion that
both descriptive and injunctive norms can elicit behavior change, with the
prominence of one or the other type of norm accounting for the direction of the
change. Second, it offers grounds for hope that certain kinds of undesirable
action (littering, drinking and driving, tax cheating, highway speeding, etc.)
can be restrained by the use of procedures that temporarily focus individuals
on injunctive norms in the settings where the action is most likely to take
place.
Study 5
To this point in our
research program, we have examined the validity of our norm focus formulation
by using an attention-focusing procedure designed to make subjects mindful of a
specific descriptive norm (Studies 1–3) or of conflicting descriptive and
injunctive norms (Study 4) governing littering in a situation. The first three
studies found resultant behavior changes wholly in line with the descriptive
norm. The fourth study, which added evidence of a contradicting injunctive norm
to the perception of the existing descriptive norm, broke the dominance of the
descriptive norm over subjects' behavior; it actually produced a
(nonsignificant) reduction of littering in an environment where a clear,
prolittering descriptive norm existed. It seemed to us that the logical next
step in this progression was to conduct one additional study that removed any
prolittering descriptive norm focus and that concentrated subjects exclusively
on the injunctive, antilittering norm. It was our expectation that such an
uncontaminated, injunctive norm focus would then lead to a significant
reduction in littering.
We saw another reason for
conducting an additional experiment. In Studies 1 through 4, our norm-focusing
manipulation involved the dropping of a noticeable piece of litter into an
environment (either by a seen or an unseen individual) so as to draw subjects'
attention to the normative information present in that environment. There were
several advantages of using that particular attention-focusing device,
including the ability to make certain nonintuitive predictions that would not
have flowed from rival theoretical accounts. We also recognized, however, that
there would be certain drawbacks to using the same procedure yet again. First,
the generality of our conceptual argument could be seen as untested beyond the
range of our specific norm salience manipulation. More important, though, using
littering to highlight the norms related to littering could create
interpretational ambiguities. That is, the littering act itself is not neutral.
It carries social meanings (depending on the situation in which it occurs) that
are likely to generate various kinds of perceptions of the littering agent. It
is possible that one or another of these perceptions could have acted to
incline subjects to follow or reject the litterer's lead. For instance,
although it is unlikely that someone who littered into a fully littered
environment, as occurred in Study 4, would be seen positively by subjects,
someone who littered into an environment of neatly swept litter might be seen
in an especially negative light; it is possible that this more negative view
may have accounted for the reduction in littering among such subjects in Study
4. Similarly, it is conceivable that subjects in Studies 1 through 3 may have
had an unpleasant reaction to any litterer who would litter into a previously
clean setting and, hence, may have failed to litter so as to distance
themselves from such an unsavory person.
To avoid interpretations
of this sort, which are based on subjects' perceptions of a litterer, it was
necessary to design a focus shift manipulation that would draw subjects'
attention to the injunctive norm against littering but would do so without the
action of a littering agent. To this end, in Study 5 we relied on the device of
cognitive priming, wherein one concept can be activated in an individual by
focusing that individual's attention on a related concept (see Higgins & Bargh, 1987, for a review). Most, although not all
(cf. Ratcliff
& McKoon, 1988), explanations of priming effects incorporate the notion of
spreading activation, which posits that similar concepts are linked together in
memory within a network of nodes and that activation of one concept results in
the spreading of the activation along the network to other related concepts (Anderson,
1976, 1983; Collins
& Loftus, 1975; McClelland
& Rumelhart, 1981). A key determinant of whether the presentation of one concept
will cause activation of another is their semantic or conceptual proximity.
If, as research by Harvey
and Enzle (1981) indicates, norms are concepts stored in a
network format, then focusing subjects on a particular norm should activate
other norms that are perceived to be semantically close to it. Moreover, the
greater the semantic proximity, the stronger should be the resultant activation.
To test this possibility, we first had a large number of norms rated as to
their similarity to the antilittering norm. Next, on the basis of those
ratings, we selected three norms that, although alike in rated normativeness,
differed in their perceived similarity (conceptual proximity) to the
antilittering norm. Finally, we included reference to one or another of the
norms on handbills that we placed on car windshields in a local library parking
lot. We expected that the handbills containing a message reminding subjects of
the most distant norm from the antilittering norm (voting) would be littered
relatively often but that as the handbill messages referred to norms rated
closer (energy conservation) and closer (recycling) to the antilittering norm,
fewer and fewer subjects would litter them. We also expected that handbills
containing no normative message would be littered most of all, whereas
handbills containing the target, antilittering message would be littered least.
Method
Preliminary Ratings Study
A list of 35 norms that had been generated by the researchers and
their colleagues (e.g., “Driving at a safe speed,” “Recycling,” “Paying taxes,”
and “Not littering”) were shown to 95 undergraduate psychology students during
a class session at a large state university. The students were asked to
indicate the extent to which they found each item on the list to be normative
or nonnormative on 9-point scales, anchored by the labelsextremely normative (1) not
at all normative (9); the
scale midpoint was labeled somewhat
normative (5). A definition
of norms was provided at the top of the list that read “Norms are shared
beliefs within a culture as to what constitutes socially appropriate conduct.”
A second list was shown to a different class of 87 undergraduate
psychology students at the same university during a meeting of their class. In
addition to the definition of norms at the top of the list, this list contained
comparisons of each of the selected norms with the norm against littering.
Subjects were asked to “indicate how closely related you believe each of the
pairs of norms are” on 9-point scales anchored by the labelsidentical(1)
and unrelated(9); the
scale midpoint was labeled somewhat
close (5). Examples of the
comparison items are “The norm against littering and the norm for recycling”
and “The norm against littering and the norm for returning library books on
time.”
Selection of the experimental norms
Means for both types of ratings were computed. The norm for not
littering was rated as 4.25 on the 9-point normativeness scale. We then limited
our choices for the additional experimental norms to those that had means for
both male and female subjects within one scale point of 4.25 on rated
normativeness. From this pool and on the basis of the similarity scale ratings,
we selected three norms to be close to, moderately close to, and far from the
norm against littering. Those three norms and their rated distances from the
norm against littering were, respectively, the norm for recycling (3.57), the
norm for turning off lights when last to leave a room (5.74), and the norm for
voting (7.12).
Generating the normative messages
For each of the four experimental norms, a message was constructed
that was suitable for presentation on a handbill. For the antilittering norm
(identical to the target norm), it read, “April is Keep Arizona Beautiful
Month. Please Do Not Litter.” For the recycling norm (close to the target
norm), it read, “April is Preserve Arizona's Natural Resources Month. Please
Recycle.” For the turning off lights norm (moderately close to the target
norm), it read, “April is Conserve Arizona's Energy Month. Please Turn Off
Unnecessary Lights.” For the voting norm (far from the target norm), it read,
“April is Arizona's Voter Awareness Month. Please Remember That Your Vote
Counts.” Finally, a control message was constructed that carried no injunctive
norm; it read, “April is Arizona's Fine Art's Month. Please Visit Your Local
Art Museum.”
Subjects and Procedure
Participants were 133 female patrons and 126 male patrons of a
municipal public library branch who parked their cars in the library lot. After
leaving the library and returning to their cars, subjects found on the driver's
side of the windshield a handbill that had been placed there by an experimenter.
The handbill carried one of the five experimental messages designed to focus
subjects differentially on the norm against littering. Drivers' decisions to
litter the handbill were recorded by an unobtrusively placed observer.
Typically, subjects who littered did so immediately after reading the handbill
message and virtually always within 5 s of having done so. Consequently, we
felt confident that the priminglike effects we anticipated were well within the
range of priming-effect durations found by other investigators (see Higgins & Bargh, 1987, for a review). No
efforts were made to change the moderate amount of naturally occurring litter on
the library grounds and parking lot, which consisted of a variety of cigarette
butts and an occasional paper cup or soft drink can.
Results and Discussion
In tests for gender
effects within the data, only the main effect was significant, χ2 (1, N = 259) = 3.92, p < .05, indicating that men littered
more frequently than women (22% vs. 14%). To examine our hypothesis that as the
conceptual distance between the antilittering norm and the handbill messages
increased, littering rates would increase commensurately, we conducted a trend
analysis. Only the predicted, linear trend (displayed in Figure
6)
proved significant, χ2 (1, N = 259) = 5.48, p < .02. Within the five experimental
message means, only one comparison was significant, that between the target,
antilittering norm (10%) and the no-norm control message (25%), χ2 (1, N = 118) = 4.87, p < .03.
Percentages of subjects littering a handbill message as a function
of its proximity to the injunctive norm against littering: Study 5
As in Study 4, focusing
subjects differentially on the injunctive norm against littering, this time
through the processes of priming and spreading activation, led to littering
rates corresponding to the predicted degree of injunctive norm focus. Thus, as
expected, subjects in Study 5 (a) littered least after encountering a message
focusing them directly on the antilittering norm, (b) littered progressively
more frequently as the encountered (equally normative) messages directed focus
progressively away from the antilittering norm, and (c) littered most when the
encountered message was not normative.
General Discussion
We began this article by
reporting the mixed support for the utility of social norms in accounting for
much of human behavior; the claim that the concept, as traditionally conceived,
possesses great explanatory power currently has strong proponents and equally
strong opponents. From the perspective of the research we have presented, it
would appear that both camps are right. Norms clearly do have a considerable
impact on behavior, but the force and form of that impact can only be usefully
understood through conceptual refinements that have not been traditionally or
rigorously applied. That is, to predict properly the likelihood of
norm-consistent action requires, first, that one specify the type of
norm–descriptive or injunctive–said to be operating. Second, one must take into
account the various conditions that would incline individuals to focus
attention on or away from the norm.
We have argued that our
experimental manipulations worked to focus subjects on descriptive norms in Studies
1 through 3, on descriptive and injunctive norms in Study 4, and on injunctive
norms in Study 5. Although the patterns of results in those studies are
consistent with that argument, there is certainly room for alternative views.
For example, it could be contended that, for subjects in Studies 1 through 3,
seeing litter in an otherwise clean environment did not simply engage the
descriptive norm against littering but engaged the injunctive norm as well.
That is, a single piece of litter may have reminded subjects of societal
objections to littering, and thus it may have been the activation of the
injunctive norm that produced reduced littering in those studies. Alternative
accounts of this sort for specific segments of our data, although not
parsimonious in explaining the overall pattern of results, remain conceivable
nonetheless.
That is so in part
because our work was conducted in naturally occurring field settings where it
was not possible to assess the precision and effectiveness of our norm-focus
manipulations through the methods typically available to laboratory
investigators. Detailed checks on the strength, specificity, and functional
impact of a subject's attentional focus could not have been practicably
administered in our research situations. The consequent absence of such
measures allows questions to arise as to whether our experimental manipulations
worked as planned. Without the corroboration of these measures, one may have
less confidence that the type of norm we intended to be functional actually
mediated our findings. Fortunately, the effectiveness of injunctive social
norms, about which there has been doubt in the scientific community (Darley
& Latané, 1970; Garfinkel, 1967; Krebs, 1970; Krebs
& Miller, 1985; Marini, 1984), has the clearest
support in our data. That is, although it does seem possible to explain our
data patterns without recourse to the well-established concept of descriptive
norms, it does not seem plausible to do so without recourse to the more
disputed and interesting concept of injunctive social norms, especially in
Studies 4 and 5. Nonetheless, future research should be done in ways that allow
direct assessments of the mediating processes presumed to be active in the
present work.
Throughout this research
program, we have exposed subjects to acute situational conditions designed to
focus them on or away from particular norms. We recognize, however, that
enduring cultural and dispositional conditions may also influence one's
normative focus. This distinction among cultural, situational, and
dispositional factors strikes us as important in the realm of norms. In
thinking about the concept, we have been led to speculate that norms function
at the cultural/societal level, the situational level, and the individual
level. Although they may not have developed such a tripartite
conceptualization, norm theorists have recognized normative influences at each
of these levels. At the first (cultural/societal) level, the influence of
global norms on behavior within a culture or social group has often been noted
(Birnbaum
& Sagarin, 1976; Paicheler, 1976;Pepitone, 1976; Triandis, 1977; Triandis, Marín, Lisansky,
& Betancourt, 1984). Indeed, many definitions of norms refer
exclusively to this level. For example, Ross (1973) considered norms to be “cultural rules
that guide behavior within a society” (p. 105). At the second level, others
have recognized that cultural norms may not apply equally to all situations (Peterson, 1982).
Consequently, definitions of norms often include an explicit situational
component. For example, Popenoe (1983) defined social norms as expectations
“of how people are supposed to act, think, or feel in specific situations” (p.
598). Finally, other social scientists have evidence that norms exist at the
individual level as well. Most notable in this regard is the groundbreaking
work of Schwartz (1973, 1977) on the concept of personal norms.
Our view is that what is
normative (i.e., most often done or approved or both) in a society, in a
setting, and within a person will, in each case, have demonstrable impact on
action, but that the impact will be differential depending on whether the actor
is focused on norms of the culture, the situation, or the self. Research is
planned to test the implications of this conception.
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3. Berkowitz, L., & Berkowitz, L. (Ed.) (1972). Advances in experimental social psychology. San Diego, CA: Academic Press.
4. Berkowitz, L., & Daniels, L. R. (1964). Journal of Abnormal and Social Psychology.
5. Bickman, L. (1972). Journal of Social Psychology.
6. Birnbaum, A., & Sagarin, E. (1976). Norms and human behavior. New York: Praeger.
7. (1988). The California litter problem. Sacramento, CA: Author.
8. Cialdini, R. B. (1988). Influence: Science and practice. Glenview, IL: Scott, Foresman.
9. Collins, A. M., & Loftus, E. F. (1975). Psychological Review.
10. Darley, J. M., Latané, B., Macaulay, J., & Berkowitz, L. (Eds.) (1970). Altruism and helping behavior. San Diego, CA: Academic Press.
11. Deutsch, M., & Gerard, H. B. (1955). Journal of Abnormal and Social Psychology.
12. Feldman, N. S., Higgins, E. T., Karlovac, M., & Ruble, D. N. (1976). Journal of Personality and Social Psychology.
13. Ferguson, T. J., & Wells, G. L. (1980). Journal of Personality and Social Psychology.
14. Finnie, W. C. (1973). Environment and Behavior.
15. Fishbein, M., & Ajzen, I. (1975). Belief, attitude, intention, and behavior. Reading, MA: Addison-Wesley.
16. Fiske, S. T., & Taylor, S. E. (1984). Social cognition. Reading, MA: Addison-Wesley.
17. Garfinkel, H. (1967). Studies in ethnomethodology. Englewood Cliffs, NJ: Prentice-Hall.
18. Geller, E. S., Winett, S., & Everett, P. B. (1982). Preserving the environment. New York: Pergamon Press.
19. Geller, E. S., Witmer, J. F., & Tuso, M. A. (1977). Journal of Applied Psychology.
20. Gruder, C. L., Romer, D., & Korth, B. (1978). Journal of Experimental Social Psychology.
21. Harvey, M. D., & Enzle, M. E. (1981). Journal of Personality and Social Psychology.
22. Heberlein, T. A. (1971). Dissertation Abstracts International.
23. Higgins, E. T., & Bargh, J. E. (1987). Annual Review of Psychology.
24. (1968). Who litters and why. New York: Public Opinion Surveys.
25. Krauss, R. M., Freedman, J. L., & Whitcup, M. (1978). Journal of Experimental Social Psychology.
26. Krebs, D. L. (1970). Psychological Bulletin.
27. Krebs, D. L., Miller, D. T., Lindzey, G., & Aronson, E. (Eds.) (1985). The handbook of social psychology. New York: Random House.
28. Manis, M., Dovalina, I., Avis, N. E., & Cardoze, S. (1980). Journal of Personality and Social Psychology.
29. Marini, M. M. (1984). Social Forces.
30. McClelland, J. L., & Rumelhart, D. E. (1981). Psychological Review.
31. McKirnan, D. J. (1980). European Journal of Social Psychology.
32. Mehan, H., & Wood, H. (1975). Reality of ethnomethodology. New York: Wiley.
33. Milgram, S., Bickman, L., & Berkowitz, O. (1969). Journal of Personality and Social Psychology.
34. Miller, L. E., & Grush, J. E. (1986). Journal of Experimental Social Psychology.
35. Paicheler, G. (1976). European Journal of Social Psychology.
36. Pepitone, A. (1976). Journal of Personality and Social Psychology.
37. Peterson, L. (1982). Merrill Palmer Quarterly.
38. Popenoe, D. (1983). Sociology. Englewood Cliffs, NJ: Prentice-Hall.
39. Ratcliff, R., & McKoon, G. (1988). Psychological Review.
40. Reiter, S. M., & Samuel, W. (1980). Journal of Applied Social Psychology.
41. Ross, H. L. (1973). Perspectives on social order. New York: McGraw-Hill.
42. Ruble, D. N., & Feldman, N. S. (1976). Journal of Personality and Social Psychology.
43. Rutkowski, G. K., Gruder, C. L., & Romer, D. (1983). Journal of Personality and Social Psychology.
44. Shaffer, L. S. (1983). Journal of Mind and Behavior.
45. Schwartz, S. H. (1973). Journal of Experimental Social Psychology.
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47. Schwartz, S. H., & Fleishman, J. A. (1978). Social Psychology.
48. Sherif, M. (1936). The psychology of social norms. New York: Harper.
49. Sherif, M., & Sherif, C. W. (1969). Social psychology. New York: Harper & Row.
50. Staub, E. (1972). Journal of Social Issues.
51. Triandis, H. C. (1977). Interpersonal behavior. Monterey, CA: Brooks/Cole.
52. Triandis, H. C., Marín, G., Lisansky, J., & Betancourt, H. (1984). Journal of Personality and Social Psychology.
53. Trope, Y., Ginnosar, Z., Bar Tal, D., & Kruglanski, A. (Eds.) (1986). The social psychology of knowledge. New York: Cambridge Press.
54. Venkatesan, M. (1966). Journal of Marketing Research.
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