I’ve often attributed the unfortunate state of public discourse at least in part to “experts’ ” refusal to admit mistakes. It may be a personal pet peeve of mine, but rings true throughout the realms of politics and economics. Why do we have such trouble admitting when we are wrong about something?
As any scientist knows, learning results from failed attempts and unexpected consequences. In fact, inherent in any academic research is an admission that we have more to learn – otherwise we wouldn’t need the research! It is reasonable, then, to expect some missteps to happen on the path to discovery. So, why can’t we say as much out loud?
Pride comes into play. Experts who err don’t want to face the embarrassment of a prediction which did not come true, so rather than admit the failure, they rationalize or, worse, double down. Starting to sound like the prophet proclaiming the apocalypse is around the corner this time (even though the last twelve times turned out to generate nothing more than unwarranted hysteria)? Sadly, it’s that kind of tactic that plagues political punditry and, at times, economic forecasting.
Nate Silver describes this phenomenon in The Signal and the Noise, in the context of predictions in the face of “out-of-sample” problems, or problems with which forecasters have little to no experience describing:
When we expand our sample to include events further apart from us in time and space, it often means that we will encounter cases in which the relationships we are studying did not hold up as well as we are accustomed to. The model will seem to be less powerful. It will look less impressive in a PowerPoint presentation (or a journal article or a blog post). We will be forced to acknowledge that we know less about the world than we thought we did. Our personal and professional incentives almost always discourage us from doing this.
We forget – or we willfully ignore – that our models are simplifications of the world.
Once we become more comfortable with the limits to our own knowledge as individuals, the conversation can truly begin.
EDIT: Here’s Silver later on:
[…] if you have reason to think that yesterdays’ forecast is wrong, there is no glory in sticking to it. “When the facts change, I change my mind,” the economist John Maynard Keynes famously said. “What do you do, sir?”