Since everyone else seems to be doing it, I thought I'd list some things where I changed my mind based on empirical data (as some sort of prior flexibility display). Unfortunately as a physicist, I don't have a lot of economics-relevant items. Actually there is just one:
- I went from believing inflation expectations at the zero bound could raise inflation to seeing that most empirical measures of expectations were backward-looking -- and therefore couldn't be a guide for much of anything in the future. In that sense I drifted from thinking Krugman was right (expectations were possible, but hard for central banks at the zero bound) to Sumner was right (expectations were easy for central banks) to both theories being either untestable and/or inconsistent with empirical data. In a sense, wrestling with this lead directly to this blog.
On most other topics in econ, I haven't formed a strong enough opinion to warrant some kind of adjustment of my priors. I kind of view the subject like I do various statistical health studies -- Drink coffee! Don't drink coffee! I'm not sure where we are on that.
As for physics/science:
- Non-zero cosmological constant. This came out while I was an undergrad and I didn't believe it at first. Since it such a serious fine-tuning problem, I thought it would be zero. More data eventually convinced me that it was a real thing.
- LIGO could successfully measure gravity waves. I used to think this would be impossible, but the papers on the calibration have made me reconsider it. I'm now just ambivalent. It has come up recently in the news and my attitude is wait and see rather than dismissal.
- Placebo effect (warning: picture of surgery at link). It's not that I didn't think it was real -- it's more that I've become more tolerant of "alternative medicines" operating through it ... in fact, a significant fraction of mainstream treatments might operate through it as well.
PS The title is a Mystery Science Theater 3000 reference.