4.2 Normality and Homogeneity
After the data were gathered, the normality and the homogeneity should be checked in order to know if the data could be analyzed.
4.2.1 Normality
Before the t-test computation, the writer had to make sure that the data were
normal.
Table 4.1 Research Data Tabulation
Experimental Group Control Group
No Code
Pre Test
Post Test
Diffe rence
No Code
Pre Test
Post Test
Diffe renc
e 1
E-01 67
86 19
1 C-01
62 80
18 2
E-02 65
85 20
2 C-02
71 75
4 3
E-03 72
83 11
3 C-03
62 76
14 4
E-04 75
89 14
4 C-04
55 76
21 5
E-05 79
87 8
5 C-05
55 72
17 6
E-06 69
80 11
6 C-06
72 73
1 7
E-07 68
81 13
7 C-07
69 78
9 8
E-08 67
86 19
8 C-08
67 74
7 9
E-09 74
90 16
9 C-09
50 63
13 10
E-10 78
84 6
10 C-10
80 80
11 E-11
72 79
7 11
C-11 56
75 19
12 E-12
67 82
15 12
C-12 53
67 14
13 E-13
75 85
10 13
C-13 62
67 5
14 E-14
72 89
17 14
C-14 61
70 9
15 E-15
82 89
7 15
C-15 63
69 6
16 E-16
67 88
21 16
C-16 60
69 9
17 E-17
76 87
11 17
C-17 64
76 12
18 E-18
60 83
23 18
C-18 60
70 10
19 E-19
70 86
16 19
C-19 78
83 5
20 E-20
62 85
23 20
C-20 59
75 16
21 E-21
64 84
20 21
C-21 63
77 14
22 E-22
61 79
18 22
C-22 68
79 11
23 E-23
69 84
15 23
C-23 54
73 19
24 E-24
55 87
32 24
C-24 64
77 13
25 E-25
55 78
23 25
C-25 73
78 5
26 E-26
72 85
13 26
C-26 58
72 14
27 E-27
66 85
19 27
C-27 58
74 16
Sum 1859
2286 -
- -
1697 1998
- Mean
68.85 84.67
- -
- 62.85
74.00 -
Variants 55.97
72 10.615
4 -
- -
55.97 72
21.30 77
-
Standard Deviation
7.48 3.26
- -
- 7.48
4.62 -
After getting the data of experimental and control group, the normality was analyzed. It was found that the X
2
of pretest and posttest of experimental
group was 0.965 and 3.193 and the X
2
of pretest and posttest of control group was 3.361 and 1.920.
Then, the results were consulted with critical value of X
2
αdk with α = 0.05 and dk = 3, whose result is 7.815. Since the value of X
2
αdk of experimental and controlled group were lower than 7.81, the data were considered
to be normally distributed. The computation of normality can be seen in Appendices 8,9,13 and 14.
4.2.2 Homogeneity
Homogeneity is important to check whether the data of each group are
homogeny or not. The computation of homogeneity goes as follow:
Use the formula stated above, the homogeneity of pretest of experimental and controlled group is computed as follow:
F = 1.0000 The result was consulted with the value of F table with dk numerator v
1
= 27-1 = 26, dk numerator v
2
= 27-1 = 26 , and α = 0.05, squared to v
1
= 27 and v
2
= 27 is 2.19. Because the F 1.81 2.19, then the data were considered to be homogeny.
While the homogeneity of posttest of both groups is computed as follow:
F = 2.0072 The result was consulted with the value of F table with dk numerator v
1
= 27-1 = 26, dk numerator v
2
= 27-1 = 26 , and α = 0.05, squared to v
1
= 27and v
2
= 27 is 2.194. Because the F 1.74 2.194, then the data were considered to be
homogeny. The computation of homogeneity can be seen in Appendices 15 and 16.
4.3 Statistical Analysis
Kategori