Probability

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I took this photo on March 31st.  It's The Girl, keeping a tally of all the numbers that come up when you roll the pictured dice.

Each of the kids has a six-sided die -- and each is a different color, so each kid knows whose is whose.  They were playing a game that's kind of like ''heads or tails'', but with six options instead of two:  everyone picks a number from one through six, and then the die is rolled until someone's guess comes up; the person with the correct guess is the winner.

(I came up with this because with three children in the house, this is more equitable than trying to do ''heads or tails'' -- where each time, someone would have to be left out of the game.)

The Girl was complaining that her die (the pink one) wasn't fair -- that it kept coming up with the same number. So, I suggested that we test it.

And, that's what we're doing:  I roll the die, and call out the result; she adds it to the tally.

As you can see, it's not **quite** evenly distributed yet:  the fours and fives are ahead.  But the other numbers are starting to catch up.

By the way:  from a statistical point of view, we'd have to roll the die 200-300 time to have a sufficiently decent baseline to determine whether the die is **truly** unbalanced.   


--GG