Section_2.1_Homework_for_scatterplots_and_correlati[1]

Section_2.1_Homework_for_scatterplots_and_correlati[1] -...

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Homework for scatterplots and correlation Here are two formulas for finding r: r n x x s y y s i x i y = - - - 1 1 r n x y n x y s s i i x y = - - ⋅ ⋅ 1 1 The first formula is the one given in the book. The second one is easier to use. Be careful - both formulas are affected by rounding-off error. 1. For each data set below make a scatterplot and find r. Before you start, look at the numbers I have chosen and notice that each set consists of the same 5 numbers. (That means that the averages and standard deviations are the same for all four sets.) The only difference is in the way the numbers have been paired. a. X Y b. X Y c. X Y d. X Y 1 1 1 1 1 1 1 6 2 2 2 2 2 4 2 4 2 2 2 4 2 2 2 2 4 4 4 2 4 6 4 2 6 6 6 6 6 2 6 1 2. In this problem, use the same 5 values of X and Y that I used in question 1. a. Find a combination that will give a value of r that is negative, but closer to 0
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This note was uploaded on 09/23/2011 for the course MATH 324 taught by Professor Staff during the Spring '08 term at S.F. State.

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Section_2.1_Homework_for_scatterplots_and_correlati[1] -...

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