I watched one of the 12-hour coin tossing marathons.
They were sitting with their laptops and pressed a button for every result.
I wonder if human error can explain (at least part of) the deviation from 50/50:
* locations of the buttons they pressed on the laptops (they only pressed once per toss before enter, meaning the button represented same-side or other-side)
* remembering what the coin started out as may be harder (or easier, but probably harder) when the result is other-side
* other??
Need to repeat this amount of tosses but with a higher degree of supervision to be sure of the result.
That's actually not completelly accurate. The study protocol (https://osf.io/hkv8p) describes the procedure in greater detail.
People were pressing one button for heads and another button for heads (which we deemend less error prone and less likely to be subcontiously influenced). The trick was that the next coin flip started the same side-up as the previous landed. Therefore there was no need to record the start (and we randomized the starting position of every 100th flip)
We also did some auditing of the video recordings (trying to decode the outcomes from the videos) and they showed quite consistent degree of bias as the original responses.
They were sitting with their laptops and pressed a button for every result.
I wonder if human error can explain (at least part of) the deviation from 50/50:
* locations of the buttons they pressed on the laptops (they only pressed once per toss before enter, meaning the button represented same-side or other-side)
* remembering what the coin started out as may be harder (or easier, but probably harder) when the result is other-side
* other??
Need to repeat this amount of tosses but with a higher degree of supervision to be sure of the result.