[sonofgod]

Hmmmm.

Let's assume that the baby has a perfect ordered ranking of blocks, 3 > 2 > 1, but that the experimenter doesn't know what it is.

There's three scenarios for what the new, third block is: 1, 2 or 3.

If it's 2 or 3, then the rejected block in the first round has a score of 1, and so we'd expect. So we'd only expect the baby to switch in a third of the cases, as opposed to 50% of the cases where the blocks are assumed to be equal.

"However, in the critical test trial that followed, 16 of 21 infants (76.2%) chose the new block (block C; Fig. 1)"

I can't work out the p-value vs. 66% compared to 50%, though...

[TimPC]

They aren’t switching though. They are given a choice between A&B then if they choose A they are given a choice between B&C. The choice between B&C should be 67/33 but instead it’s around 75/25 and the authors claim this is because in not choosing B the baby decided they liked B less. The evidence for this claim is that if an adult makes the first choice for the baby then the 2nd choice is 50/50.

[MauranKilom]

Monty Hall strikes again!