What if the child didn't much care for marshmallows, and reasoned that spending 15 minutes of their life waiting for an extra marshmallow was an incredible waste of time?
Funny; but seriously the kids enter the room knowing "Im taking part in a serious Adult study of my behavior." They likely try to behave as they're expected to behave. The real test is, how soon does the feeling of obligation decay to the point that the appeal of a marshmallow (admittedly insignificant) outweights the desire to please.
My Sister took her youngest to an experiment where, in the waiting room they put the kid in a room with toys on a table, and took her to 'do paperwork'. The boy was told to leave the toys alone.
Really she went to the observation room. They simply timed how long it took for the bored child to play with the toys.
See, by testing the child 'before the test started' they avoided pre-loading the kid. They changed-up the test by having other kids and adults enter the room and play with the toys, or repeat the admonition, or whatever.
My Sister took her youngest to an experiment where, in the waiting room they put the kid in a room with toys on a table, and took her to 'do paperwork'. The boy was told to leave the toys alone.
Really she went to the observation room. They simply timed how long it took for the bored child to play with the toys.
See, by testing the child 'before the test started' they avoided pre-loading the kid. They changed-up the test by having other kids and adults enter the room and play with the toys, or repeat the admonition, or whatever.
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