PROTEUS

              

 

 

 

 

 

 

 

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Solution in detail.......#43

 A(lecture)    B(Hands-on)    C(AVMedia)

         63                 82                     71

         59                 92                     82

         71                 75                     66

         59                 74                     71

         65                 87                     73

Σ     317              410                   363

N        5                  5                       5

     63.4             82.0                 72.6

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Null hypothesis: That there is NO real difference between means of three instruction methods and that any observed difference is only due to random (chance) error.  [Ho: a=b=c]

 

Total SS:      Σx2   –   (Σx)2        =        80,546  -   10902        =         1339.333     

                               N                                          15

 

Btw-gps SS:  (TA)2  + (TB)2  + (TC)2  –    (Σx)2    =   3172  + 4102  +  3632  -  10902   = 864.933   

                     NA             NB            NC             N                5           5            5          15

 

Within Grps SS:     TSS –  BSS     =       1339.333   –   864.993      =      474.400

 

ANOVA

ss

df

ms

F

P

bss

864.933

2

432.467

10.939

<0.01

wss

474.400

12

39.533

 

    

tss

1339.333

14

                           calculated F: 10.939          critical F(0.01)(2,12 df) :  6.93

              therefore can reject Ho.     P<0.01

There was a difference between the means that is unlikely (less than 1% likely) to have been due to chance alone. We can reject the null hypothesis and claim statistical significance at 0.01 level    The highest (best) score was from method B (82), followed  by method C (73), while the lowest score was associated with method A (63)