Unformatted text preview: . 67 SS y = s ( y 2 )( ∑ y ) 2 n = 3623136 9 = 13 . 56 SS x = s ( x 2 )( ∑ x ) 2 n = 3773249 9 = 16 . 00 r = SP xy r SS x SS y =. 67 r (16 . 00)(13 . 56) =0.05 Regression: b = SP xy SS x =. 67 16 . 00 =. 04 ¯ Y = ∑ y n =56 . 00 / 9 =6 . 22 , ¯ X = ∑ x n =57 . 00 / 9 =6 . 33 a = ¯ Y( b )( ¯ X ) =6 . 22(. 04)(6 . 33) =6 . 49 Y p = bX + a = Y p =(0.04)(X)+(6.49) Prediction: at x = 4, the prediction for y = (. 04)(4)+6 . 49 =6.32 Standard Error of Prediction: s y  x = R SS y (1r 2 ) n2 = R 13 . 56(1(. 05) 2 ) 92 = 1.39 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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 Fall '08
 Ard
 Statistics, Normal Distribution, Regression Analysis, Standard Deviation, major mode

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