The criteria of the test: α = 0.05
H
o
: F
αn1-1, n2-2
F F
αn1-1, n2-2
H1: F F
αn1-1, n2-2
The formula used can be seen as follows
1
:
or
The calculation can be seen as follows: 1.028
n1-1 = 39-1 = 38 n2-1 = 39-1 = 38
F
0.05n1-1, n2-1
=
1.84 F
table
From the calculation, it can be seen that F F
α n1-1, n2-2
1.028 1.84. Based on the criteria, it can be conclude that H
o
is accepted. It means that the sample in experiment class and controlled class were homogenous.
C. Hypothesis Testing
The researcher calculated the data to test the hypothesis that whether there is significant different between students’ reading ability in descriptive text in
experiment class which given the technique of numbered heads together and students’ reading ability in descriptive text in controlled class without given the
technique of numbered heads together. Two classes were compared, the experiment class was X variable and the controlled class was Y variable. She used
the result of post –test of experimental class and controlled class. She used statistic
calculation of the t-test formula with degree significance 5 in the following table:
1
Budi Susetyo, Statistika Untuk Analisis Data Penelitian, Bandung: PT Refika Aditama, 2010, p.160
Table 4.7 The result calculation of post
– test of experimental class
Score F
X X
fx x
2
fx
2
45 – 52
4 48.5
3 12
9 36
53 – 60
6 56.5
2 12
4 24
61 – 68
6 64.5
1 6
1 6
69 – 76
15 72.5
77 – 84
7 80.5
-1 -7
1 7
85 – 92
1 88.5
-2 -2
4 4
N = 39 ∑ =
21 ∑ =
67
Based on the table above, the researcher would like to establish the mean, standard deviation and standard error of variable X. The calculation will be
described in the following steps: 1.
∑ = 72.5 + 8 21 = 76.80 N
39
2. √∑
– ∑ = 8
√ – = 9.55
N N
39 39
3. SE
mx
= SD
x
= 9.55 = 9.55 = 1.550
√
x
– 1 √ 6.16
Table 4.8 The result calculation of post
– test of controlled class
Score F
Y Y
Fy y
2
fy
2
40 – 47
3 43.5
3 9
9 27
48 – 55
6 51.5
2 12
4 24
56 – 63
8 59.5
1 8
1 8
64 – 71
13 67.5
72 – 79
6 75.5
-1 -6
1 6
80 – 87
3 83.5
-2 -6
4 12
N = 39 ∑ =
17 ∑
2
= 77
∑ = 67.5 + 8 17 = 71.02 N
39
√∑ – ∑
= 8 √ –
= 10.68 N
N 39
39
6. SE
my
= SD
y
= 10.68 = 10.68 = 1.733 √
y
– 1 √ 6.16
7. SE
mx-my
= √
= √
= 2.323
8. t
o
= =
= 2.488
