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Current time:0:00Total duration:2:09

Frequency stability property short film

Video transcript

consider the following imagine two rooms inside each room is a switch in one room there is a man who flips his switch according to a coin flip if he lands heads the switch is on if he lands tails the switch is off in the other room a woman switches her light based on a blind guess she tries to simulate randomness without a coin then we start a clock and they make their switches in unison can you determine which lightbulb is being switched by a coin flip the answer is yes but how the trick is to think about properties of each sequence rather than looking for any specific patterns for example first we may try to count the number of ones and zeros which occur in each sequence this is close but not enough since they will both seem fairly even the answer is to count sequences of numbers such as runs of three consecutive switches a true random sequence will be equally likely to contain every sequence of any length this is called the frequency stability property and is demonstrated by this uniform graph the forgery is now obvious humans favor certain sequences when they make guesses resulting in uneven pattern such as we see here one reason this happens is because we make the mistake of thinking certain outcomes are less random than others but realize there is no such thing as a lucky nerve there is no such thing as a lucky sequence if we flip a coin ten times it is equally likely to come up all heads all tails or any other sequence you can think of