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Math Help - Statistics Least Squared - Midterm Tomorrow!

  1. #1
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    Statistics Least Squared - Midterm Tomorrow!

    By the method of least squares, fit y = Bx to the following n=6 points.

    x 3 1 5 6 3 4
    y 4 2 4 8 6 5
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  2. #2
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    How about y = 1.25x. Good luck on that exam.
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  3. #3
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    how did you decide on 1.25?
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  4. #4
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    Well, it didn't really matter since your exam is today. If you don't know already, you're probably toast.

    I would have preferred y = (36/23) + (41/46)x, with the usual Normal Equations, but you insisted that the intercept is zero, so that limited the choices and the least squares approximation turned out to be y = 1.25x.

    Thus: B \cdot \sum{x^{2}}\;=\;\sum{xy} \implies B\;=\;\frac{120}{96}\;=\;1.25

    Have you met Normal Equations? They ARE important.
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  5. #5
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    ha you're right i had no idea how to do that problem today! oh well i answered every other question with ease thanks tho
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