**Unformatted text preview: **11 = 155 . 64 SS x = s ( x 2 )-( ∑ x ) 2 n = 234-1296 11 = 116 . 18 r = SP xy r SS x SS y = 25 . 55 r (116 . 18)(155 . 64) = 0.19 Regression: b = SP xy SS x = 25 . 55 116 . 18 = 0 . 22 ¯ Y = ∑ y n = 53 . 00 / 11 = 4 . 82 , ¯ X = ∑ x n = 36 . 00 / 11 = 3 . 27 a = ¯ Y-( b )( ¯ X ) = 4 . 82-(0 . 22)(3 . 27) = 4 . 10 Y p = bX + a = Y p =(0.22)(X)+(4.10) Prediction: at x = 8, the prediction for y = (0 . 22)(8)+ 4 . 10 = 5.86 Standard Error of Prediction: s y | x = R SS y (1-r 2 ) n-2 = R 155 . 64(1-(0 . 19) 2 ) 11-2 = 4.08 Note: On the exam you should round all intermediate results to 2 decimal places. However the fnal answers on this key were computed using higher precision, thereFore there may be rounding discrepancies with solutions computed rounding at every step, especially For prediciton....

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