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DEPARTMENT OF SOCIOLOGY
The social transmission of choice: An exploratory computer simulation with
applications to “hegemonic discourse”
Edmund [email protected]
Plan of the talk
• The problem: The status of rational choice theory (RCT).
• A solution: Simulating the social transmission of choice.
• The simulation: Assumptions and results.• Application: Hegemonic discourse.• Further research.• Conclusions.
The status of RCT• There is something hard to refute about the core of RCT: If
an agent has a set of payoff information about a range of choices and if they fail to use that information then they are being not just irrational in regard to RCT but also irrational in an everyday sense.
• The status of the theory: Is it a paradigm or an empirical theory?
• Testing the theory: If it is an empirical theory, isn’t it falsified by experimental (and other) data?
• The details of the theory: Are other choice processes (sequential decision) “rational” in a world of limited time or cognitive capacity?
A fairly new objection• What is the status of the assumption that everyone shares
the same description of the choice set?
• Lots of models exist in which actors learn about payoffs but in all of these (as far as my reading takes me) they are still assumed to share knowledge of the choice set.
• Small literature on “framing” in experimental economics: How do people make strategic choices when they recognise that others may see the world differently. (Example of colour discrimination and matching.)
• None of this research addresses the following sociological question: What happens if choice sets are not shared and when social transmission of choice occurs?
Some appealing implications• Choice and traditional action become part of the same framework. A
tradition exists where only a single action is “available”.
• Makes more sense of everyday talk about choice (and deceit):– “Donnaconna, chief of the town of Stadcona, tried to keep Cartier from visiting Hochelaga by
magnifying the difficulties and dangers of the route, hoping to keep the trade and the middle-man’s profit for himself…”
– “The greatest triumphs of propaganda have been accomplished, not by doing something, but by refraining from doing. Great is the truth, but still greater, from a practical point of view, is silence about truth.”
– ““But I had to stay with him,” answered the vampire. “As I’ve told you, he had me at a great disadvantage. He hinted there was much I didn’t know and must know and that he alone could teach me. But in fact, the main part of what he did teach me was practical and not so difficult to figure out for oneself.” … “… rising before me he might have nailed my coffin shut. Or set it afire. The principal thing was, I didn’t know what he might do, what he might know that I still did not know.””
• Starts to make sense of other everyday phenomena like gossip, collective memory, socialisation and situational (ethnographic) rationality.
A simulation• Simulation: Presentation of a social theory as a
computer programme rather than a narrative (qualitative) or statistical model (quantitative).
• Written in NetLogo which is free, cross platform and comes with a models library. You can download the software and start experimenting with it almost immediately: <http://ccl.northwestern.edu/netlogo/>.
• Code available from the author on request.• I will describe the assumptions but not the technical
details: Like trusting SPSS to do the statistics correctly or NVIVO not to forget codes for an interview.
Basic assumptions• There are two types of entities in the world: Agents
and “situations”.
• Agents move around and can communicate with each other when they meet.
• Situations stay still and produce different payoffs in response to different actions by agents.
• When an agent encounters a situation, they choose what to do, picking the action that will maximise expected payoff, given what they currently know.
The structure of decision• For each situation, each agent has a list representing their beliefs about payoffs
to different actions. For example the list (5 3 nil nil nil) would mean that the agent expects a payoff of 5 from action 1, 3 from action 2 and does not know that actions 3-5 would yield payoffs in this situation.
• In addition, each agent also has a list representing the confidence with which they believe they are likely to achieve each payoff. So, for example, if you have tried a particular action in response to a particular situation, you have total confidence in being able to achieve that payoff again (in this simplified static environment). Conversely, if someone else tells you that they think a particular action might yield a good payoff, neither having tried it or heard about anyone else who has, you might assign that a low confidence of 0.2.
• The expected utility of each action is simply the product of the payoff and the confidence.
• Important: When you try an action, you get the actual payoff which may be different from your previous belief about it.
Innovation and initialisation• Each time an agent faces a situation, it may occur to them,
with a rather small probability, that they could try a different action than those they know about. Associated with this idea comes a belief about the likely payoff (evenly distributed over the whole range of possible payoffs -10 to 10) and a standard initial level of confidence (0.5).
• At the start of the simulation, each agent knows only a single “traditional” action (no choice) for each situation and this yields a small but positive payoff. It is also assigned a confidence of 1 since it has been tried many times by the simulated society.
Communication• When two agents meet, they exchange information about their choice sets.
Each randomly chooses a situation to report on and (again randomly) a payoff to a particular action to communicate.
• This gives rise to two possibilities:
• One agent knows the choice exists and the other doesn’t. In this case, the payoff of the knowledgeable agent is transmitted to the ignorant agent and so is the confidence but at a reduced level (0.1 subtracted).
• Both agents know the choice exists. This gives rise to two further possibilities:
• They agree on the payoff. In this case, the confidence of both agents is boosted by 0.1 reflecting reinforcement of their views.
• They disagree on the payoff. In this case, their payoffs are averaged but their confidence remains the same.
Notes on communication• The only way to get a confidence of 1 is to try something
yourself. Otherwise, the maximum confidence you can achieve is assumed to be capped at 0.9.
• Because of confidence, an untried action has to promise a payoff that is better than that of a previously tried action. This promise is the “reward” for taking the risk that the belief about the new action may be wrong. The less confidence the agent puts in their payoff belief, the more substantial the reward must be.
• Alternative assumptions need to be explored and ideally identified empirically. (This is not trivial.)
The demographic process• Agents live 80 periods.
• New agents are born and these are identical to a randomly selected existing agent.
• The birth and death processes are adjusted solely to stabilise the population. (The demographic process is not the main interest of the simulation but immortal agents seem rather likely to end up rational eventually.)
The dynamics of choice transmission• Innovative actions spread in their “entirety” to ignorant agents.
Prior to choice there must be recognised possibilities for choice.
• There is a blending of ideas about payoffs to untried actions but agents who have tried these act as a constant source of reliable payoff information to the system.
• The rise and fall of confidence based on communication may make untried actions appealing. When they are tried, additional accurate payoff information is fed back into the system.
• We can now ask an important question: Why (and under what circumstances) does this process not lead to the situation assumed in RCT, namely, shared choice sets and payoffs for all agents?
Sample simulation screen
Coverage: Knowledge of choice set
Accuracy: Correctly known payoffs
Optimality: Payoff to best known choice
Limits to the evolution of RCT• Belief traps (Mackie): If something appears bad,
even if it isn’t, it will not be tried and thus the misbelief will not be falsified.
• “Reflective equilibrium” is likely to be suboptimal and “perfect” socialisation will do nothing to change it.
• Ironically, the drive to try new options partly results from the unconditional adoption of information by the ignorant!
Hegemony• What happens when there are two groups and
one of them is dominant?
• The choice information transmitted by the majority group is “hegemonic” but may be harmful to the minority. (As an acid test, the simulation assumes that payoffs are exact opposites for two groups so 3 for majority is -3 for minority).
Coverage
Both groups learn the whole choice set: Interestingly, the minority learns it faster. (“Gay eye for the straight guy”.)
Accuracy
No significant differences in accuracy for groups but much lower than in homogeneous population.
OptimalityHegemonic result: Best choices of minority significantly worse than those of majority and in reflective equilibrium.
Tentative interpretation• Positive results from majority tried by minority.
• This means they know as much about choices but end up with more negative (and therefore unused) actions in their choice set.
• Minority have to find the positive options for themselves and suffer from scarcity of information.
• Interestingly, hegemony penalty is “likely” but not invariable.
Discussion• Formal analysis: Parameter space. (More situations,
actions and so on.)
• Exploration: Understanding dynamics of choice transmission.
• Literature analysis: More grounded assumptions (belief updating, communication, decision processes, socialisation).
• Data gathering: Dearth of information about real world belief updating processes in real time. Experiences of minorities in hegemonic contexts.
Conclusions• Rationality is a blessing if you have a correct
understanding of the choice set but a curse if you don’t. In social contexts, you probably don’t but economics tends to ignore or fudge this point.
• The quality of RCT as an explanation depends on things like frequency of experience, social complexity, socialisation processes, group homogeneity and so on. We can’t use simple evolutionary arguments to justify a RCT world.
• Simulation helps us understand social processes in new ways: Maslow and the hammer!