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CPS1844 Reza M.
            Figure 3: Empirical CDFs of sample IPDs for Iris data. From top to bottom, the
            ECDFs are   (red),   (brown),   (green) grouped together followed by the
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            ECDFs of    (blue),    (pink) and   (black).
                                                
            Example 4 We consider the wine data set (Asuncion and Newman, 2007),
            which contains 178 rows of data on concentrations of 13 different chemicals
            in wines grown in the same region in Italy. The wine types are from three
            cultivars of grapes: Barolo, Grignolino, and Barbera. There are 59, 71, and 48
            observations on each type of wine. Barolo wine is made from Nebbiolo grapes,
            the other two wines have the name of the grapes from which they are made.
            Univariate  analysis  shows  that  the  wine  measurements  have  very  different
            scales  and  the  three  wine  types  are  well-separated.  Barolo  wines  contain
            distinctly  higher  amounts  of  Proline  than  wines  from  either  Barbera  or
            Gringnolino.
            Suppose X, Y, and Z represent the three cultivars of grapes, Barolo, Grignolino,
            and Barbera, respectively. The wine data set gives rise to mean IPDs of  =

                                                                                     




            253.25,  = 176.69,  = 133.86,  = 599.83,      = 488.99, and    = 186.07.
                                 
                                             
                     
            Figure 4 shows the six ECDF plots of the within and between IPDs. Clearly, the
            null hypothesis H0 : Gx = Gy = Gz is false. In fact, the plots support the alternative
            Ha : Gz ≤ Gy ≤ Gz.



















            Figure 4: Empirical CDFs of the IPDs for three varieties of wine. The ECDFs from
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            top to bottom are   (brown),   (black),    (pink),   (red),    (green), and
                                                                
                                            
                                
              (blue). The IPDs clearly support the alternative Ha : Gz ≤ Gy ≤ Gz.
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