Hi I have a question on probability which I am not sure of.(adsbygoogle = window.adsbygoogle || []).push({});

If you have a coin and flip it 20 times then of course the probability of getting H or T is 0.5. And even in 20 flips you should roughly get a 50% distribution, correct?

Now what if to each side of the coin you affix a number, #1 for H, #2 for T.

And before each flip of the coin, you randomly switch the the numbers affixed to each surface.

After flipping the coin another 20 times, both the H-T distribution and the 1-2 distribution should be ~50% right?

Ok now before each coin flip, let's say the numbers 1 and 2 are switched in some non-random way. For example, the rankings of two players in a sport (although I'm not sure if this is considered truly non-random from the perspective of the coin).

Now you flip the coin another 20 times and you still get a ~50% distribution for H-T, but the distribution for 1-2 is very skewed, let's even say 100% '1'. Looking at the H-T distribution it seems normal and random, but looking at the 1-2 distribution one has reason to suspect something is unusual.

Is there a reason to think that someone could have tinkered with the coin flip process to get this skewed distribution or is it not completely abnormal for this very skewed distribution since 1-2 were apparently not switching randomly?

Hope that made sense.

Thanks.

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# Coin flip question.

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