Ok, so yesterday I tweeted this:
It received a fair bit of attention. This is my attempt to explain the context. Please bear in mind that I am neither a statistician nor a scientist of any kind. These are just my reflections on a portion of education policy class last night that I found confusing. If you have anything more interesting and/or more accurate to say about randomness and/or predictability, then please chime in.
We were discussing different models of the policymaking process. Traditional/rational models posit that the process proceeds from deliberation about the problem, to identification and evaluation of all possible solutions, to implementation and evaluation, all in an organized, reason- and/or evidence-governed way.
On the contrary, an alternative model, the “garbage can model,” expresses and depends on the idea that policy choices are not made in such an organized, rational way. Rather, there are various “streams” contributing to the outcome: problems themselves and how they are defined, politics, and policies. The confluence of all these factors results in a kind of “organizational anarchy,” in which multiple streams collide to influence policy outcomes, often in ways that are unintended by policy actors. It’s apparently called the “garbage can” model in order to emphasize how the various policy factors are all just sort of mixed together in a container, like garbage, and that the way they collide and converge is disorderly. There’s a concise description of the model here, if you’re interested.
In discussing the garbage can model, my prof switched between saying that the outcome was “random” and “unpredictable,” as if the two are interchangeable in this context. In fairness to him, other authors writing about the garbage can model around the internet seem to have a tendency to do the same thing. However, I think this can’t be quite right. Like I said, I’m no expert on the meanings or applications of the concept of randomness. But, to me, as a student in a policy class, what “random” conveys is that all of the possible policy outcomes are equally as likely to clump together in the garbage can and ultimately get selected. That’s just got to be false; some policies are surely more likely to be selected than others. For instance, ceteris paribus, a policy benefiting business leaders with lobbyists may be more likely to be selected than a policy benefiting a small and non-vocal group of grassroots activists. The policy outcomes may seem random, because we can’t tell why a certain blend of factors resulted in them, but that doesn’t make the process actually random. Saying that the garbage can process is “unpredictable” is fine, though. The factors that contribute to the process are many, varied, difficult to observe, and difficult to measure. Also, note that this process could be both random and unpredictable, in which case it would be unpredictable in virtue of being random. But I don’t think that’s the case here.
The reason this matters is because if the garbage can model of education policy is true and accurately described as “random,” then the appropriate response is to become thoroughly pessimistic about the possibility for anyone or any group to influence policy outcomes. After all, that would mean that, as soon as the policy factors mix up in the garbage can, they become equally likely to be selected. So why even bother? But unpredictability is weaker – it suggests that we don’t know everything about the policy process and should be realistic about our prospects for influencing it, our ability to avoid unintended consequences, etc., without dismissing the possibility altogether.
Updating to add: None of this is to say that the garbage can model is worthless. It helpfully reminds us that policy work is very, very messy. It just isn’t random.