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CNN, exit polls, and chi-square examples.

CNN posted a whole mess of exit polling data that illustrates how different demographics voted last night. And through my "I teach too many stats classes" lense, I see many examples of chi-square.

I think they work at a conceptual level to clearly illustrate how chi-square looks at people falling into different categories, then measures whether the distribution of people is by chance or not.

If you actually wanted to test these using chi square, I would suggest you should problem delete the other/no answer column (or else they will all come out as statistical significant, I would wager).






EDIT (11/14/16); Daniel Findley made of video demonstrating how to use Excel to conduct chi-square tests on the marital status data. Check it out here.

Comments

  1. Thanks for all your great suggestions. I put together a video based on your recommendations - because of the large sample size, I went into further analysis to show how the p-value changes as the sample changes.. If you have any thoughts/suggestions, I'd welcome any feedback you have.

    https://youtu.be/XMMw_TkTytQ

    ReplyDelete
    Replies
    1. Looks great. I'll share the link with my readers and add it to this post.

      Delete
    2. My only suggestion, and it is a little one, is label each table (is that expected data? Is it modified in some way?).

      Delete
    3. Good suggestion, I'll update the associated excel file that can be downloaded.

      Delete

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