Case Study: Testing Confirmation Bias

I support your focus on testing confirmation bias, but I don't think that it was worth it to explicitly falsify results (for a short time), compared to saying "oh well" and repeating the process until you do legitimately get an inconvenient result on a self-experiment. You've demonstrated that you're willing to break the taboo (or injunction) of never falsifying object-level results of scientific experience, which makes all of your data less valuable.

I found this to be a good and informative post, nonetheless.

This was possibly an expensive experiment in terms of social capital...

I think it would have been better to have waited longer. After only three days, his response seems reasonable. Perhaps after two weeks, it would be more difficult to believe that he would have ever published your data.

Andrew Gelman also has a post up today about Seth Roberts not being diligent about seeing disconfirmatory evidence: Selection Bias

Edit: Seth makes several responses, including this succinct claim to have avoided confirmation bias: comment

And testing confirmation bias in this fashion is intrinsically deceptive, so I probably have damaged my online reputation as well.

I have no way to back this up and just posting this tastes like hindsight bias to me. Nonetheless, this was my train-of-thought when I read this post :

1. Gwern is using what looks like normal communication as a means to experiment.
2. Gwern is a data-crunching, prediction-making, experiment-performing, freak-of-nature. (I mean this in an extremely complimentary fashion.) Therefore:
3. This wasn't the first time Gwern did something like this and it will not be the last time.

Of course, as Rational!Beyonce would say "If I thought it then I should have put a prediction on it."

And testing confirmation bias in this fashion is intrinsically deceptive, so I probably have damaged my online reputation as well.

Yes, this test might not have passed a university ethics review - not only did you deceive your subject, which must be done carefully, but he didn't even know he was participating in an experiment!

Amateur Science -
I do what I must,
because, I can.
For the good of all of us.
Except the ones who were tricked.
But there's no sense crying over all the missed frills,
You just keep on trying until you run out of pills.
And the Science* was fun,
And you get neat posts done
For the people who are, still alive.

And testing confirmation bias in this fashion is intrinsically deceptive, so I probably have damaged my online reputation as well.

It's interesting that you mentioned that, because I spent several minutes after reading this being confused, and then I thought:

"It is at least hypothetically possible Gwern is testing confirmation bias with THIS post to Less Wrong."

That was followed by "What evidence would I be looking for to confirm or disprove this hypothesis?"

Which was followed by "It would probably take to much reading to plausibly gather sufficient evidence to make any kind of judgement, and I don't have that much time to assess this post. I'll just put my assessment of this experiment on hold until more verification arrives either way on whether it is or is not a meta experiment."

Was this the kind of reputation damage you were expecting?

Post summary: I, Gwern, am better than Seth Roberts. Watch as I trick him with my superior science skills! This is important, because I have proven that a human is biased, something no one has ever done before.

In the end, what did we learn from the results of this experiment?

(Please take a moment to think about this yourself before proceeding, to avoid priming.)

My answer: Nyzbfg abguvat. Ernfbaf jr qvqa'g yrnea nalguvat nobhg Eboregf:

1) Onfrq ba jung lbh jebgr urer, vg ybbxf yvxr Eboregf punatrq uvf zvaq nobhg gur rssrpgvirarff bs Mrb orgjrra jura lbhe rkcrevzrag fgnegrq naq jura vg raqrq. Guvf tvirf uvz n cresrpgyl yrtvgvzngr ernfba gb cebgrfg ntnvafg lbhe qngn.

2) Bar vagrenpgvba vf fvzcyl abg rabhtu gb tnhtr ubj ovnfrq n crefba vf. Gurer ner znal pbasbhaqvat inevnoyrf urer, naq guvf vf na a = 1 fnzcyr. Eboregf' erfcbafr znl unir orra nssrpgrq ol uvf zbbq, ubj zhpu ur ngr sbe oernxsnfg, naq nal ahzore bs bgure guvatf. Nf lbh fnvq va gur cbfg, a = 1 rkcrevzragf whfg nera'g tbbq fbheprf bs qngn.

3) Rira vs gurfr ceboyrzf jrer pbeerpgrq sbe, tvira gung gur onfr engr sbe pbzzvggvat pbasvezngvba ovnf vf cebonoyl irel uvtu, C(Eboregf vf zber cebar gb pbasvezngvba ovnf guna gur nirentr vaqvivqhny|guvf rkcrevzrag) vf oneryl uvture guna C(Eboregf vf rdhnyyl cebar gb pbasvezngvba ovnf pbzcnerq gb gur nirentr vaqvivqhny|guvf rkcrevzrag). Ubjrire, vs lbh pbhyq pbeerpg sbe gur ceboyrzf V yvfgrq nobir, guvf xvaq bs rkcrevzrag jbhyq or fbzr rivqrapr ntnvafg "Eboregf eneryl snyyf cerl gb pbasvezngvba ovnf."

Gur rkcrevzrag cebirq rira yrff nobhg pbasvezngvba ovnf, zbfgyl sbe gur ernfbaf fgngrq nobir. Nqqvgvbanyyl, Eboregf vfa'g n ercerfragngvir fnzcyr bs nyy uhzna orvatf, naq bar vapvqrag yvxr guvf vfa'g rabhtu gb tvir rivqrapr nobhg n oebnq gurbel yvxr pbasvezngvba ovnf.

Va fhzznel: Guvf rkcrevzragny erfhyg vf vaqvfgvathvfunoyr sebz abvfr, naq qenjvat pbapyhfvbaf sebz vg jbhyq or hawhfgvsvrq.

And testing confirmation bias in this fashion is intrinsically deceptive, so I probably have damaged my online reputation as well.

If anything, you should have more deceptive and convoluted plots if you want to maximize interesting drama.

satt points out that (via the Bienaymé formula) “An RCT with a sample size of e.g. 400 would still be 10 times better than 4 self-experiments by this metric.”

Since this has come up again, I may as well point out that this is a very abstruse argument.

• First of all, if the standard error in a random variable is low to begin with, or I've already done many experiments, decreasing the standard error of my estimate by a factor of 10 is much less valuable.
• And second of all, this analysis doesn't connect with anything actionable. What does decreasing the standard error of my estimate by a factor of 10 even mean in actionable terms? How often will this actually end up changing what I do?

The way I'm thinking about this argument is to picture a normal distribution representing my uncertainty about some value. When I do 100 times as many experiments, the distribution

• becomes skinnier by a factor of 10, and
• centers itself at a new location, where the probability of the new location is determined by the original distribution. If my original distribution is especially wide, more experiments could be valuable, especially if the new distribution ends up jumping somewhere far from the center of the original distribution. But if my original distribution was plenty skinny to begin with, making it skinnier won't help me.

See also this comment of mine, which does math showing that just a few perfectly done self-experiments can be quite valuable in actionable terms: http://lesswrong.com/lw/bs0/knowledge_value_knowledge_quality_domain/6d9k

Great work!

Just out of curiosity, what would you have done if he'd published and linked to the incorrect results? While this version of the story causes you some social damage (gwern is deceptive), wouldn't the damage have been much worse if he'd passed the confirmation bias test?

Very nicely done! While the sensible thing would have been for him to link to your results, going after Zeo seems like a reasonable thing to do, given {reviews like this one](http://www.amazon.com/review/R1S2WQ7K7ZWERL/ref=cm_cr_dp_title?ie=UTF8&ASIN=B002IY65V4&nodeID=3760901&store=hpc).

Two technical glitches: the graph is too large and the relevant portion is blocked by the sidebar, and clicking the gwern.net link sends me to a different essay.

Excellent work - thank you!

Cult-like behavior. Post has essentially no info (trivial on the specific case, redundant with known when - improperly - generalized) about the topic ostensibly about.

Rich in info on Gwern. Gwern values blah1 over blah2. He knows, or should know, LessWrong will approve of this (on balance, exhibiting personal commitment to investigation versus violation of norms against, etc). Outside LessWrong will not approve of this. Indeed, the cost Gwern pays personally (outside LessWrong) only shows greater personal commitment (to LessWrong), so contributes more to upvoting. But really just character estimation. Post itself is virtually valueless outside that. The attempt to justify this as an important case (previously discussed by cult leader) is dopey (and, if true, broad evidence of dopeyness). And, of course, costs paid by LessWrong more than Gwern. This is the behavior folks will (correctly) think of as LessWrongian. You (general) mostly don't think about that (cultish). Too late to downvote post now.