flipping coins

When you ask a turker to flip a coin, it will land on heads about 2/3 of the time. There is an interesting series of blog posts about this: Coin Flipping, Coin Flipping with Bonuses, Coin Flips Revisited, and even more recently Michael Bernstein repeated the experiment with 1000 turkers and got 687 heads.

So when Google consumer surveys came out, I asked Allison Moberger to post a question for me: "Please flip an actual coin and choose the result below," with the options of "Heads" and "Tails".

We went for the smallest experiment allowed by Google, which is 1000 people, at $0.10 per question, so $100.

The result: 65.9% heads.

I didn't realize this, but even though you pay for 1000 people, Google doesn't have demographic information on everyone who answers, and it throws out people it doesn't know about. Hence, this 65.9% is from 794 'respondents with demographics', and I'm not sure how to see what the remaining 206 people did. [EDIT: Jack Hebert says "To see all 1000 responses, click on the 'gear' icon then set 'Prefer weighted' to Off." He's right. Thanks Jack! He also mentioned that I can share the data. Apparently it is public by default, so here's the link.]

The demographics are cool though, and they automatically look for statistically significant differences among the demographics, called "Insights". It says "124 insights investigated. 2.5 false discoveries expected on average." There were indeed two insights, so they're probably both false: "Among women, those in the US South picked Heads more than those in the US Northeast." and "Among people in the US South, women picked Heads more than men."

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