406 E.-S. Park J. of Economic Behavior Org. 43 2000 405–421
In his recent paper, Andreoni 1995 has suggested that much of the cooperation observed in public good provision experiments may be due to framing. In order to examine the effects
of positive and negative framing on the level of cooperation in public goods experiments, Andreoni considered two different framing conditions: 1 the positive-frame condition, in
which subject’s choice is framed as contributing to a public good that makes other subjects better off and; 2 the negative-frame condition, in which subject’s choice is framed as buying
a private good that makes other subjects worse off. By conducting public goods experiments under these two conditions, Andreoni finds that contribution rates are considerably lower
under the negative-frame condition than under the positive-frame condition. His arguments that much of the cooperation observed in public good provision experiments may be due to
framing seem to be very convincing as the contribution rate to the public good converges to the Nash equilibrium by the end of iterations under the negative frame.
3
The main objective of this paper is to examine the robustness of Andreoni’s findings regarding the existence of a positive–negative asymmetry. Given that previous voluntary
public good provision experiments by many authors reported a high variance in contribution rates among subjects, it may be that some people are more sensitive to framing than others.
In particular, this paper concerns whether such a behavioral asymmetry exists uniformly across the subjects who have different value orientations Liebrand, 1984; Offerman et al.,
1996, i.e. different preferences regarding one’s own welfare relative to the welfare of oth- ers. In order to study the framing effects on the subjects with different value orientations,
data on individual value orientation were first obtained using the Decomposed Game exper- imental design Liebrand, 1984; Offerman et al., 1996. Then Andreoni’s experiment was
replicated.
The major finding of this experiment is that while there is a significant difference between the two framing conditions in terms of overall contribution rates, there is no significant
difference for some subjects. In particular, the data strongly suggest that the negative framing has a most salient effect on the subjects who have individualistic value orientation, whereas
the negative framing has a rather insignificant effect on the subjects who have cooperative value orientation.
In Section 2, differences between experiments with positive and negative externalities are first discussed. A brief account on value orientations developed by social psychologists
is then followed. In Sections 3 and 4, the experimental design and results are presented, respectively. Section 5 contains concluding discussion of the experimental results.
2. Framing effects and value orientations
In this section, I describe essential features of the framing-effects experiment and the value orientation experiment.
3
There are many other studies on framing effects with inconclusive findings. The finding of Brewer and Kramer 1986 is not consistent with Andreoni’s, and no significant effects were found by Rutte et al. 1987, Fleishman
1988, and Messick et al. 1993. More recently, Sonnemans et al. 1998 found a framing effect in a public goods versus public bads environment. Even though their work is in the context of step-level public goods bads, it has
some similarities to the current paper in the experimental design, which will be discussed later.
E.-S. Park J. of Economic Behavior Org. 43 2000 405–421 407
2.1. Positive and negative framing This subsection closely follows Andreoni 1995 and readers are referred to his original
paper for detailed description. Subjects play in groups of five. Each subject is given 60 tokens. Every token placed in
the private good x
i
earns one cent for subject i, while every token given to the public good g
i
earns one half cent for all five group members. Thus, subject i’s problem is to maximize π
i
= x
i
+
1 2
g
i
+ 1
2 X
j 6= 1
g
j
, 1
subject to the budget constraint x
i
+ g
i
= 60. Thus, in this positive frame, an action of con-
tributing to the public good will generate a positive externality for other subjects. The positive frame instructions to subjects include “Every token you invest in the Individual
Exchange will yield you a return of one. Every token invested in the Group Exchange will yield a return of one half for every member of the group, not just the person who invested
it. It does not matter who invest tokens in the Group Exchange. Everyone will get a return from every token invested — whether they invest in the group exchange or not’.
In order to convert this positive frame into a negative frame, Andreoni first reminds us that saying that an investment in the public good will make others better off is equivalent
to stating that an investment in the private good will make others worse off. That is, the above positive frame can be converted into the negative frame by substituting the budget
constraint of the other players, x
j
+ g
j
= 60, into the objective function 1:
π
i
= x
i
+
1 2
g
i
+ 1
2 X
j 6=i
60 − x
j
2 π
i
= x
i
+
1 2
g
i
− 1
2 X
j 6=i
x
j
+ 120.
3 This negative frame is expressed in the negative frame instructions to the subjects in the
following way: “Every token you invest in the Individual Exchange will yield you a return of one. However, each token you invest in the Individual Exchange will reduce the earnings
of the other players by one half cent each. . . It will also be true that when the other members of your group invest in the Individual Exchange then your earnings will be reduced by 12
times their investment in the Individual Exchange. . . Every token you invest in the Group Exchange yields a return of 12 for you”. Also, in order to provide the same incentive for
the subjects under the two different frames, each subject gets automatic earnings of 120 each round.
In Andreoni’s experiment, 40 subjects are used in each condition. The data are collected in four different sessions, two sessions for positive frame experiments and the other two for
negative frame experiments. For each session, 20 subjects are recruited from intermediate level economics classes at the University of Wisconsin — Madison. Table 1 lists his findings
in the experiments. There is a considerable difference in contribution rates under the two framing conditions and on average, the subjects in the negative frame condition contribute
48.2 as much as the positive-frame subjects.
408 E.-S. Park J. of Economic Behavior Org. 43 2000 405–421
Table 1 Mean percent of tokens contributed to the public good Andreoni, 1995
1 2
3 4
5 6
7 8
9 10
All Positive
47.5 48.6
44.2 32.7
36.5 34.8
21.3 25.6
23.7 20.9
33.58 Negative
27.8 24.1
18.1 19.5
16.1 14.3
16.5 12.9
11.7 1.0
16.20 Difference
19.7 24.5
26.1 13.3
20.3 20.5
4.9 12.7
12.0 19.9
17.38
The framing effect can also be seen by looking at the propensity of subjects to free ride under the two conditions. Table 2 lists the percent of subjects choosing the strategy of
free-riding i.e. no tokens to the public good. On average, 63.5 of negative-frame subjects free ride in any round, which is almost twice the rate of positive-frame subjects.
2.2. Value orientations This subsection is based on Offerman et al. 1996. According to many social psy-
chologists people have different goals when they make decisions that affect others. Social psychologists have developed the concept of value orientation that represents the weight
an individual attaches to one’s own welfare to the welfare of other individuals Offerman et al., 1996, p. 817. Five value orientations are often discussed: competitive, individualistic,
cooperative, altruistic, and aggressive. Competitors want to be better off than others; indi- vidualists want to do best for themselves; cooperators try the best for both themselves and
the others; altruists want to do best for others, regardless of the outcome for themselves and aggressors try to do worst for others, regardless of the outcome for themselves Offerman et
al., 1996, pp. 818–819. Most people are classified either as individualistic or cooperative Liebrand, 1984; Offerman et al., 1996. For example, in Offerman et al.’s experiment, 65
of the subjects were labelled individualistic, 27 of them were labelled cooperative, 4 of them were labelled competitive, 1 of them were labelled aggressive.
The Decomposed Game experiment Liebrand, 1984; Offerman et al., 1996 is often used to assess individual value orientations. In this experiment each subject’s task is to
make a series of 24 choices between two options. Each option specifies an amount of money to the decision-maker and an amount to another subject with whom the individual is
anonymously paired during the experiment. These two options are two adjacent vectors of 24 equally spaced vectors on the circle, x
2
+ y
2
= 15
2
see Fig. 1. For example, the subjects are asked to choose between Option A=3.90, 14.50 and Option B=7.50, 13.00, where
Option A allocates 3.90 points for self and 14.50 points for the other and Option B allocates
Table 2 Mean percent of subjects free-riding Andreoni, 1995
1 2
3 4
5 6
7 8
9 10
All Positive
30.0 25.0
27.5 37.5
32.5 32.5
40.0 40.0
37.5 42.5
34.5 Negative
47.5 55.5
55.5 55.5
60.0 70.0
62.5 70.0
70.0 90.0
63.5 Difference
17.5 30.0
27.5 17.5
27.5 37.5
22.5 30.0
32.5 47.5
29.0
E.-S. Park J. of Economic Behavior Org. 43 2000 405–421 409
Fig. 1. The value orientation circle.
7.50 points for self and 13.00 points for the other. The 24 decision problems are listed in Appendix A.
Social psychologists use the observed motivational vector, the sum of the individual’s 24 chosen vectors, to classify individual’s value orientations. Subjects with an observed
motivational vector lying between degree −112.5 and −67.5 are classified aggressive, subjects with vectors between −67.5 and −22.5 are classified competitive, subjects with
− 22.5 and 22.5 are classified as individualistic, subjects with vectors between 22.5 and
67.5 are classified as cooperative, and subjects with vectors between 67.5 and 112.5 are classified as altruistic see Fig. 1.
3. Experimental design
