Research Methodology - Dr. Krishan K. Pandey

282 Research Methodology
Brands of gasoline
W X Y Z
A 13 12 12 11
11 10 11 13
Cars B 12 10 11 9
13 11 12 10
C 14 11 13 10
13 10 14 8
13. The following are paired observations for three experimental groups concerning an experimental involving
three methods of teaching performed on a single class.
Method A to Group I Method B to Group II Method C to Group III
X Y X Y X Y
33 20 35 31 15 15
40 32 50 45 10 20
40 22 10 5 5 10
32 24 50 33 35 15
X represents initial measurement of achievement in a subject and Y the final measurement after subject
has been taught. 12 pupils were assigned at random to 3 groups of 4 pupils each, one group from one
method as shown in the table.
Apply the technique of analysis of covariance for analyzing the experimental results and then state
whether the teaching methods differ significantly at 5% level. Also calculate the adjusted means on Y.
[Ans: F-ratio is not significant and hence there is no difference due to teaching methods.
Adjusted means on Y will be as under:
For Group I 20.70
For Group II 24.70
For Group III 22.60]