About the “Learning” section:
I think I understand the basic argument here: sometimes an escalation of commitment can be rational as a way to learn more from a project by continuing it for longer. But it seems like this only applies to some cases of sunk cost thinking and not others. Take Thaler's example: I don't see why a desire to learn would motivate someone to go to a football game in a blizzard (or, more specifically, how you'd learn more if you had paid for your ticket than if you hadn't).
And in some cases it seems like an escalation of commitment can hinder learning. Learning from a failed project often requires admitting that you made a mistake. One of the motivations for continuing a failing project is to avoid admitting you made a mistake (I believe that's called the “self-justification” explanation of the sunk cost fallacy). If you finish the project you can pretend that there was no mistake, but if you stop it prematurely you have to admit your error which can allow you to learn more. For example, if you throw out food from your plate then it's clear that you cooked too much (learning!), but if you eat everything on your plate to avoid wasting it then the error's less clear.
At the end of that section there's a list findings that “snap into focus” if escalation of commitment is for learning, but with many of them I don't see a clear connection to the learning hypothesis. For instance, “in situations where participants can learn and update, we should expect sunk cost to be attenuated or disappear” seems consistent with many different theories of sunk costs, including the theory that it's a bias which people can learn to avoid as they gain more experience with a type of decision. Is there something specific about the cited studies that points to the hypothesis that escalation of commitment is for learning?
Take Thaler's example: I don't see why a desire to learn would motivate someone to go to a football game in a blizzard
You'd learn more what it's like to go in a blizzard - maybe it's not so bad. (Personally, I've gone to football games in non-blizzards and learned that it is bad.) If you knew in this specific instance, drawn from all the incidents in your life, that you wouldn't learn anything, then you've already learned what you can and sunk cost oughtn't enter into it. It's hard to conclude very much from answers to hypothetical questions.
...seems con
I just finished the first draft of my essay, "Are Sunk Costs Fallacies?"; there is still material I need to go through, but the bulk of the material is now there. The formatting is too gnarly to post here, so I ask everyone's forgiveness in clicking through.
To summarize:
(If any of that seems unlikely or absurd to you, click through. I've worked very hard to provide multiple citations where possible, and fulltext for practically everything.)
I started this a while ago; but Luke/SIAI paid for much of the work, and that motivation plus academic library access made this essay more comprehensive than it would have been and finished months in advance.