STA113: Probability and Statistics in Engineering

Anscombe Data Sets

anscombe.1

anscombe.2

anscombe.3

anscombe.4

each with eleven observations of two variables we'll call X and Y. Look at the following Minitab session:

 MTB > read 'anscombe.1' into c1-c2
Entering data from file: anscombe.1
      11 rows read.
 MTB > name c1 'X' c2 'Y'
 MTB > regress c2 1 c1; 
 SUBC> fits = c3;
 SUBC> resid = c4.

 The regression equation is
 Y = 3.00 + 0.500 X
 
 Predictor       Coef       Stdev    t-ratio        p
 Constant       3.000       1.125       2.67    0.026
 X             0.5001      0.1179       4.24    0.002
 
 s = 1.237       R-sq = 66.7%     R-sq(adj) = 62.9%
 
 Analysis of Variance
 
 SOURCE       DF          SS          MS         F        p
 Regression    1      27.510      27.510     17.99    0.002
 Error         9      13.763       1.529
 Total        10      41.273
 
 MTB > name c3 'Fit' c4 'Res'
 MTB > plot c4 c3
 
  Res     -                                             *
          -
          -
       1.2+               *              *
          -
          -
          -
          -          *
       0.0+                         *         *                   *
          -                                        *
          -
          -     *
          -
      -1.2+
          -
          -                    *
          -                                                  *
            ----+---------+---------+---------+---------+---------+--Fit     
              5.0       6.0       7.0       8.0       9.0      10.0