I made a little experiment like that myself when I was studying for my Masters. In the town where I live there is a bus card system that uses scratch cards. You get a card with dates (1-31), months and four years (say 2012 to 2016) and you're responsible yourself for scratching off the seven days, month and year when you intend to use the card. So, if you want to use the card starting next Monday, you'd scratch off dates 23 to 29, October and 2017. Then you show it to the bus driver when you board the bus. The understanding is that if you scratch off the wrong days, you can't use the card.
Obviously, mistakes can and do happen. A couple of times I noticed I had scratched off the wrong days or month, or even year. Once I scratched off eight days. One of those mistakes (can't remember which) was noticed by a driver, but most seemed oblivious to the fact my card was irregular, at least (if not totally invalid).
So I decided to make my little experiment: I kept buying and scratching (correctly) a new card each week, but I also kept on me the previous week's card and showed this one to the driver. Then I marked a tick on the card for each time I was waved through without a batting of an eylid. I got about a dozen cards like that, each with a week's worth of ticks or so. I got caught exactly once (at which point I just said "oops, mistake" and took out the right card).
Outcome: we have refuted the null hypothesis that people see what they're looking at.
> we have refuted the null hypothesis that people see what they're looking at.
I remember a police officer pulling over my parents car, asking for the vehicle papers, checking them for 2 good minutes, and saying everything was fine, we were free to go.
After a few kilometres, my father suddenly noticed that he had given the copper the papers of a totally different car than the one in which we were...
It is like at the border, when customs officers flip the pages of your passport while looking at you. They spend as much time on white pages than on the ones that matter; in fact they just watch you and extend the time they watch you by pretending to check something, hoping their magical skills will allow them to detect if you get nervous because you are guilty of something.
I made a little experiment like that myself when I was studying for my Masters. In the town where I live there is a bus card system that uses scratch cards. You get a card with dates (1-31), months and four years (say 2012 to 2016) and you're responsible yourself for scratching off the seven days, month and year when you intend to use the card. So, if you want to use the card starting next Monday, you'd scratch off dates 23 to 29, October and 2017. Then you show it to the bus driver when you board the bus. The understanding is that if you scratch off the wrong days, you can't use the card.
Obviously, mistakes can and do happen. A couple of times I noticed I had scratched off the wrong days or month, or even year. Once I scratched off eight days. One of those mistakes (can't remember which) was noticed by a driver, but most seemed oblivious to the fact my card was irregular, at least (if not totally invalid).
So I decided to make my little experiment: I kept buying and scratching (correctly) a new card each week, but I also kept on me the previous week's card and showed this one to the driver. Then I marked a tick on the card for each time I was waved through without a batting of an eylid. I got about a dozen cards like that, each with a week's worth of ticks or so. I got caught exactly once (at which point I just said "oops, mistake" and took out the right card).
Outcome: we have refuted the null hypothesis that people see what they're looking at.