Decision Making In Prisoner’s Dilemma

11.6 Discussion

We found that cheap talk had effect on our subjects’ willingness to cooperate and on their expectations of their opponents’ willingness to cooperate in the Prisoner’s Dilemma. We did not attempt to determine the influence of cheap talk on actual behavior during an actual Prisoner’s Dilemma game – there are several studies of this problem, though, mostly corroborating that there is a positive influence of cheap talk on cooperation.

There are at least three explanations why cheap talk might work: a) group identity and solidarity is developed, b) “cheap” but public promises and commitments are made, c) cooperative norms are primed. We confirmed here, specifically, the influence of non-binding promises and commitments.
a) Group identity and solidarity. There is a switch from individual to group goals. Mere talking in the group enhances the feeling of belonging, which enhances cooperation among members of the group (Brewer & Kramer, 1986; Thompson et al., 1998; Pilisuk et al., 1965 – Pilisuk and his colleagues are convinced that the feeling, perception or attitude of “we” or of “common fate” that enhances cooperation develops also during playing itself).
b) Promises and commitments. This mechanism underlying the effectiveness of pre-play discussion has been repeatedly confirmed (Sally, 1995). Mulford et al. (2008) presume that making a public commitment leads to the need to keep one’s word (it would be interesting to test the effect of public pre-play commitment on players who engage in the upcoming play anonymously – for example via computer network). Opponents are also expected to cooperate, because they made their promises (Mulford et al., 2008; Kerr & Kaufman-Gilliland, 1994). Some degree of initial trust is thus created.
c) Cooperative norms are most likely instilled when pre-play discussion takes form of solving a “coordination problem” (what will happen, how to react, who does what, who talks, who listens, is everything clear, when to begin, etc.). Coordination norms are thus primed and they can subsequently enhance cooperation in the game tasks (Orbell et al., 1988; Bicchieri, 2002).

12. Personality variables

12.1 Task

We will be looking for possible relations between certain “personality” characteristic of subjects (friendliness, dominance, risk avoidance, and tolerance for ambiguity) and certain measures of cooperation and success in the Prisoner’s Dilemma game.

As I noted in section 6.22 Terhune (1968) proposed several reasons for the often somewhat unsatisfactory results of personality-related studies of experimental strategic games. For example Wiliams et al., 1969 pointed out that various personality dispositions (such as Internationalism, see Lutzker, 1960; McClintock et al., 1963; see also section 6.22, paragraph (5)) previously found to be related to cooperativeness were not found to be related to it on replication. The most important reason for problematic results concerning personality influences in strategic behavior might be this:
“The simple effects of personality were inconsequential compared to their more complex effects, such as the joint effects of two or more personalities in interaction, and the interaction between personality and situational influences; statistically, "main effects" of personality were minor compared to their "interaction effects"” (Terhune, 1968, p. 3).
Other reasons include variability of results due to chance factors, irrelevant variables selected for examination, and validity and reliability issues (Terhune, 1968). I was vaguely aware of these risks even before reading Terhune’s study, that is why I intended the “personality” related part of my research – described in the present section – only as a “pilot” study that might possibly yield some “hints” for a more elaborate study in this area.

12.2 Procedure

We used data obtained in the single-move games and the fifteen 30-move games played with each subject (section 8.44), we also used data obtained for testing the cheap talk hypothesis (see section 11.2).

We asked subjects to rate themselves on scale 1 (totally agree) to 10 (totally disagree) in friendliness, tolerance for ambiguity, dominance, and risk avoidance.
The following brief descriptions were given to the subjects:
A friendly person is well-wishing, kindly, gentle, warm, disposed to help and support, sometimes sentimental. If you have these qualities to a very high degree, write down 10, if you do not possess these qualities at all, write down 1 (this would mean, you are stern, unsupportive, unsentimental, sometimes even hostile).
To be tolerant for ambiguity means you are not bothered or stressed by vague, uncertain, incomplete, or inconsistent information, tasks, and situations. You do not see things as black, or white, and you are not bothered at all by opposing opinions. If you have these qualities to a very high degree, write down 10, if you do not possess these qualities at all, write down 1.
A dominant person is assertive, competitive, independent, seeks control over others, rather tells than asks. A dominant person can be sometimes stubborn, even aggressive. The opposite of dominant is submissive. If you are highly dominant, write down 10, if you are highly submissive, write down 1.
If you avoid risk that means you prefer safe prospects over risky ones (even if the risky prospects might be more profitable if all goes well), and/or you withdraw from situations that involve risk (e. g. you never bet or gamble). If you avoid risk as much as possible, write down 10, if you never avoid risk, write down 1.
We used multivariate regression analysis to determine whether the “personality” variables and the particular variables from our Prisoner’s Dilemma experiments are related.

12.3 Variables

We compared the newly obtained data for variables “45”, “46”, “47”, and “48” using regression analysis with several of the previously obtained variables.

The independent variables were:
Variable “45”: Friendliness
Variable “46”: Tolerance for ambiguity
Variable “47”: Dominance
Variable “48”: Risk avoidance
The dependent variable was, successively, each of the following:
Variable “3”: Subject’s gain during his third encounter with Tit for Tat in moves 1-25
Variable “6”: Subject’s gain during his third encounter with Random in moves 1-25
Variable “9”: Subject’s gain during his third encounter with Benevolent in moves 1-25
Variable “12”: Subject’s gain during his third encounter with Deterrent in moves 1-25
Variable “15”: Subject’s gain during his third encounter with Bully in moves 1-25
Variable “20”: Subject’s summary gain in all iterated games in moves 1-30
Variable “37”: The frequency of C choices played by the subject in moves 1-30 in all Tit for Tat conditions (for 10 moves)
Variable “38”: The frequency of C choices played by the subject in moves 1-30 in all Random conditions (for 10 moves)
Variable “39”: The frequency of C choices played by the subject in moves 1-30 in all Benevolent conditions (for 10 moves)
Variable “40”: The frequency of C choices played by the subject in moves 1-30 in all Deterrent conditions (for 10 moves)
Variable “41”: The frequency of C choices played by the subject in moves 1-30 in all Bully conditions (for 10 moves)
Variable “42”: The frequency of C choices played by the subject in moves 26-30 in all Closed conditions (for 10 moves)
Variable “49”: The willingness to cooperate (the amount of C choices) stated by the subject in moves 1-10 (in condition X)
Variable “50”: The willingness to cooperate (the amount of C choices) stated by the subject in moves 11-20
Variable “51”: The willingness to cooperate (the amount of C choices) stated by the subject in moves 21-30
Variable “52”: The willingness to cooperate (the amount of C choices) on the opponent’s part expected by the subject in moves 1-10
Variable “53”: The willingness to cooperate (the amount of C choices) on the opponent’s part expected by the subject in moves 11-20
Variable “54”: The willingness to cooperate (the amount of C choices) on the opponent’s part expected by the subject in moves 21-30
Variable “56”: The willingness to cooperate (the amount of C choices) stated by the subject in moves 1-10 (in condition Y)
Variable “57”: The willingness to cooperate (the amount of C choices) stated by the subject in moves 11-20 (in condition Y)
Variable “58”: The willingness to cooperate (the amount of C choices) stated by the subject in moves 21-30 (in condition Y)
Variable “59”: The willingness to cooperate (the amount of C choices) on the opponent’s part expected by the subject in moves 1-10 (in condition Y)
Variable “60”: The willingness to cooperate (the amount of C choices) on the opponent’s part expected by the subject in moves 11-20 (in condition Y)
Variable “61”: The willingness to cooperate (the amount of C choices) on the opponent’s part expected by the subject in moves 21-30 (in condition Y)