About cookies, Skinner boxes and the addictive Candy Crush
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A few days ago, near my office, there was a promotional event for some random brand of cookies. You could get a box for free, but only if you picked a winning ball in the mouth of a dragon statue.
I lost, but a friend shared its cookies. While crunching them, I wondered about all this staging. Why organizing a game of luck? Why designing a dragon statue?
It seems it's all about reinforcement, a concept in behavioral psychology. All of this is optimized so that I remember having received - or not - a box of cookies that day.
From Wikipedia: B.F. Skinner was a well-known and influential researcher who articulated many of the theoretical constructs of reinforcement and behaviorism. It used so-called Skinner boxes to study and change the behavior of animals.
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Among many ways to perform behavioral reinforcement, one of the most effective is the "Variable ratio schedule" one. It means having a reward every N events on average, i.e. not always at exactly N retries.
That kind of reinforcement is "rapid, steady rate of responding; most resistant to extinction". No wonder if casinos still exist!
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Such addictive schemes are used in game design. Candy Crush is a notable example of addictive gaming, read for example https://www.theguardian.com/science/blog/2014/apr/01/candy-crush-saga-app-brain