How to flip a coin in your head

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Oh yes, just quickly convert letters to numbers and then add them up in your head. Personally I’d have to use my fingers to count off letters. Just in my head, I could probably get a 3 letter word like tip done in about 5 minutes.



An alternative I can think of would be think of or look for a random word, and count the number of letters. Same thing: even=heads, odds=tails.

That said, that’s just an off-the-cuff idea, I don’t know how good I’d be at coming up with a word in a way that has 50/50 chance of being even or odd-lettered.

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“Mindhacker” sounds like a serial killer who leaves fiendishly clever clues made of the brains of his victims! At least, until Clarice Starling caught him.


With in any given language, average word length is not exactly random, and wold bias towards heads or tails.

Udo Strauss, Peter Grzybek, Gabriel Altmann
one of many studies out there, the first one Google showed.

But when it comes to randomness, it is about perception of randomness, when it comes down to if we accept it was a “random” or “fair chance” decision.

A stats class I took was split into two parts. The teacher had left some instructions in an envelope and a note on the board. They were not in the class. One had pennies and had to generate a long set of random h/t flips and note them. The other had to make up a random set of h/t flips and note them, but they couldn’t use anything other than their own brains. The teacher left the room and in all but one class, he could easily guess what group had the pennies and what group had no tools at all. People have trouble conceiving what randomness looks like on large data scales. The one group that beat him, put six heads (or tails) next to each other, then two the opposite, and then four the same after among what looked like a good random set. There were a few other long streaks of heads or tails in the 50 flips, if I remember correctly.

That professor has semi retired, but I still bump into him once in a while. He still chuckles over that, and I think he would caution using most mental only techniques.

That said, sometimes if the brain is the only tool around, then use what one has. Then again- if you need an answer now and I can’t think about it, then it’s no. I’m not flipping a mental coin if it is going to cost me some dosh.


I just pick a side - I have a 50% of it being random.


This is kind of a huge misconception that people with autism spectrum disorders are all just like Dustin Hoffman’s character in Rain Man. Autism doesn’t give people math super powers


It actually does with some. I had a classmate that could do it.

I wonder if this would be quicker/easier: look at one random word, anywhere in your eyesight. If the second letter is a vowel, it’s “heads”. Consonant is “tails”. And if your eye scans to find a word with the outcome you want, then you were going to cheat anyhow.

It still isn’t a true 50/50 solution, but it beats the crap out of trying to think of a random word and then counting the letter values and adding them, and avoids the bias of defaulting to certain words, or words of a certain length, in an attempt to game the solution.

If there are no sources of preexisting words near you, then congratulations. You’ve managed to isolate yourself magnificently.

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Yeah, but seriously, it’s harmful to stereotype people with autism.


Well, that’s how to flip a coin in my head.

But how do I flip a coin in your head?

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I would like to develop a full set of AD&D-compatible mental algorithms.

thanks, I’ll keep that in mind if I ever do that.

i liked the author’s earlier work in the early 2000s


You’ve been informed you are pushing harmful stereotypes by @ Humbabella, which is fine the media puts out a lot of garbage. But now that you’ve been brought up to speed please don’t explain at us.


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Friends tell me I have a 100% chance at being random, but I’m not so certain. :smiley:


Hmmm… apart from the difficulty of doing this in your head, it’s not exactly even odds.

Taking a list of 65 common 3- and 4-letter words:

the, and, for, are, but, not, you, all, any, can, had, her, was, one, our, out, day, get, has, him, his, how, man, new, now, old, see, two, way, who, boy, did, its, let, put, say, she, too, use, that, with, have, this, will, your, from, they, know, want, been, good, much, some, time, what, were, then, when, word, said, each, many, like, long, make

and writing a quick program in the browser console, I find that that there are 35 even words and 30 odd words, or 54%-46% split.

Edit: Ohh, interestingly, taking the 125 most common English words instead gives me 55:70, a 44%-56% split – slightly worse but the other direction. That’s not to say these cancel each other out, though – the first list is a subset of the second, but with a cut-off for word length, which apparently significantly affects the results.

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plus you can make a rainbow table of “even” or “odd” words and pick a ZOMG “RANDOM” one maliciously :metal:

this is the only time i can mention this semi-useless skill, so please humor me.

i realized as a teen that i could do this effortlessly in my head. i was waiting for laundry to finish washing and just knew that Whirlpool was 23, 8, 9, 18, 12, 16, 15, 15, 12. i never made an effort to memorize the numbers, i just could do it instantly when i tried.

i used to do it as a pretty lame party trick. mostly i do it in my head on car drives when im bored and see road signs and billboards. i add up different words and it feels satifying to get one that comes to a nice round number like 100.

when im adding up like that, i also add “points” for “contained spaces” like B would be 2, but the 2 contained spaces would make it worth 4 in my game. lower-case b would be 2+1=3.

Boing = 2(+2),15(+1), 9(+1 for the dot in the eye), 14, 7(+1) = 52.