# Day 133: Is it Fair?

Last week I was perusing Twitter and saw Bob Lochel’s post about “clay dice are drying.”  I wanted to know more, so Bob posted a blog entry Statistics Arts and Crafts about his Chi-Square GOF activity.  We are starting GOF today in AP Stats, so no time to have my students make their own die this year (sigh, would have loved this experience for them…but there’s always next year).

I loved the idea but how could I simulate the basic idea of a non-regular die being or not being fair?!  I racked my brain when suddenly I remembered my recent purchase of these dice.  I’m not sure the photo shows how irregular these dice are, but they really are!

Using Bob’s basic plan, I adjusted to fit these cute little puppies.  Each group got to choose a differently shaped but irregular die.

Through the activity, kids learned about the parts of a Chi-Square GOF situation, about components and about the shape of a Chi-Square distribution.  I think my statisticians were surprised that the oddly shaped die was actually fair.  Love this aspect of the activity!  What seems to be true isn’t always true…and statistics helps us look at our world through an unbiased lens.

I do plan to get some air drying clay and having my students make their own dies next year.  I think if students try to make their die fair and it isn’t (or is) is much more motivating than using pre-made dice.