Over the summer, Eliezer suggested (approximately, I am repeating this from memory) the following method for making an important decision:
This was essentially the method I used in coming to my (probably slightly low) estimate of the probability that Knox and Sollecito were innocent. It just felt like they were innocent, and I saw essentially no reason to suspect they were guilty. I will note that the 'pro-guilt' site that komponisto linked to was just horribly devoid of anything that I might consider evidence (if anything, that site did more to convince me of Knox's innocence than the pro-innocence site), and I did spend probably about 10 minute trying to find some evidence that they had missed, but completely failed.
On a different not, as I said at the time, 0.95 and 0.05 were just proxies for "pretty damn sure" and "pretty damned unlikely" - I have very little idea what 5% probability feels like, and I'm sure that if arbitrary scientific convention had settled on some different number for significance, I'd have picked that one instead. I have made some progress since a year ago on calibrating my estimates of small probabilities, but I absolutely do not think that I would be wrong approximately 1 time in 20 when making predictions to which I assign a probability of 0.95.
I have very little idea what 5% probability feels like
???
1d20!!!
Continuing my interest in tracking real-world predictions, I notice that the recent acquittal of Knox & Sollecito offers an interesting opportunity - specifically, many LessWrongers gave probabilities for guilt back in 2009 in komponisto’s 2 articles:
Both were interesting exercises, and it’s time to do a followup. Specifically, there are at least 3 new pieces of evidence to consider:
Point 2 particularly struck me (the press attributes much of the acquittal to the expert report, an acquittal I had not expected to succeed), but other people may find the other 2 points or unmentioned news more weighty.
2 Probabilities
I was curious how the consensus has changed, and so, in some spare time, I summoned all the Conscientiousness I could and compiled the following list of 54 entries based on those 2 articles’ comments (sometimes inferring specific probabilities and possibly missing probabilities given in hidden subthreads), where people listed probabilities for Knox’s guilt, Sollecito’s guilt, and Guede’s guilt:
It’s interesting how many people assign a high-probability to Knox being guilty; I had remembered LW as being a hive of Amanda fans, but either I’m succumbing to hindsight bias or people updated significantly after those articles. (For example, Eliezer says .15 is too high, but doesn’t seem otherwise especially convinced; and later one reads in Methods of Rationality that "[Hagrid] is the most blatantly innocent bystander to be convicted by the magical British legal system since Grindelwald's Confunding of Neville Chamberlain was pinned on Amanda Knox.")
EDIT: Jack graphed the probability against karma:
2.1 Outliers
If we look just at >41% (chosen to keep contacts manageable), we find 12 entries out of 54:
I have messaged each of them, asking them to comment here, describing if and how they have since updated, and any other thoughts they might have. (I have also messaged the first 12 commenters or so, chronologically, with <41% confidence in Knox’s guilt, with the same message.) The commenters:
AngryParsley / Cyan / Daniel_Burfoot / Eliezer_Yudkowsky / GreenRoot / John_Maxwell_IV / LauraABJ / Mario / Matt_Simpson / Morendil / Psychohistorian / Shalmanese / Threads / Unknowns / badger / bentarm / bgrah449 / bigjeff5 / brazil84 / dilaudid / jimmy / kodos96 / lordweiner27 / mattnewport / nerzhin / tut
I look forward to seeing their retrospectives, or indeed, anyone's retrospectives on the matter.