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I like practical statistics, for example when betting red/black in a casino, what is the chance that you would lose 10 times in a row ? Just keep doubling they say, but eventually you will get a bad streak and wont have enough money or you'll hit the limit.


If it landed on red 10 times in a row so far, the odds of landing another red on the next round are almost 50%. Gambler's fallacy is so much fun to observe at the tables though :)


Under the assumption that it is a fair table. So what is the likelihood that it is a fair table knowing that 1% of tables play 80% red?


In The Newtonian Casino (Might be called something else in the US) students who built computers in their shoes (in the 1970s!) to predict the outcome of roulette wheels discovered that lots of wheels had pretty severe tilts (which affected outcome) and that skilled croupiers had a "signature" -- they knew that particular wheel very well, and had practiced many times, and could increase their chance of hitting a particular number. (This is described in the chapter titled "Lady Luck").

It's a good book!

https://www.amazon.co.uk/Newtonian-Penguin-Science-29-Aug-19...


It's supposedly possible to predict to a reasonable degree of accuracy where a roulette ball will land if you know its speed (ie time it hits the wheel, and time to pass a predefined marker).

https://www.insidescience.org/news/physics-knowledge-can-til...


Also: Don't forget green. The 0 and 00 slices of the wheel are green because that's where the house makes their money.


I remember an experiment in high school math of some variety.

The teacher had us all "guess" what twenty coin flips would look like. The longest any streak any student wrote on their paper was maybe 4-ish in a row or something.

He then had us all actually flip the coins and record the results. One student had like 11 in a row, most hit a streak of somewhere between 5-8 of the same result.

Lesson learned, we're really bad at guessing 50/50 streaks.


Empirically, you should (~85% of the time) be seeing a streak of about 3-6; anything 8 or larger has a probability of about 1 in 20.


To a rough approximation, 20 coin flips gives you 16 chances to get a 1/16 probability event of 5 in a row of heads or tails, so the average number of 5-streaks is 1 per student. With 32 kids a class, add 5 more to the streak length to expect to see.




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