Students’ Number Post-test
Student 28 60
Student 29 81
Student 30 85
Student 31 75
Student 32 73
Student 33 76
Student 34 70
Student 35 73
Student 36 63
Student 37 65
Student 38 70
Student 39 70
Student 40 73
Total 2942
Average ∑
73.55
The writer compared the data in both pre-test and post-test score. The highest score in pre-test was 72 and the highest score in the post-test was 85. Meanwhile, the
smallest score in pretest was 40 and the smallest score in post-test was 60. In addition, the tables indicate that the mean of pre-test score was 62.27 and the mean of
post-test score was 73.55. It means that the mean of post-test is higher than the mean of pre-test, so the writer concludes that there was an improvement in students’ score
in writing narrative text after they were taught by using story mapping technique.
2. Analysis of Data
From the data above, the writer analyzed the data using t-test in both manual calculation and using SPSS 20. This analysis was done to examine the difference of
score between pretest and posttest. First, the writer manually analyzed the score from pre-test and post-test by calculating the result score into the formula as follows:
1. Seek D Diference between score of variable I X and score of variable II Y
and then D = X-Y 2.
Add D then getting ∑ D
Table 4.4 The Comparison Score of X The Students’ Pre-test Score to Y The
Students’ Post-test Score
Students N
Pre-test Post-test
Gain Score D D
2
X Y
X-Y 1
58 70
-12 144
2 60
76 -16
256
3
72 85
-13 169
4 43
65 -22
484
5 65
80 -15
225
6 65
75 -10
100
7 68
70 -2
4
8 40
68 -28
784
9 64
80 -16
256
10 68
75 -7
49
11 72
82 -10
100
12 57
70 -13
169
13 62
70 -8
64
14 60
76 -16
256
15
63 77
-14 196
16 60
80 -20
400
17 68
75 -7
49
18 65
67 -2
4
19 68
70 -2
4
20
60 78
-18 324
21 50
72 -22
484
22 71
70 1
1
23 61
83 -22
484
24 70
72 2
4
25 60
78 -18
324
26 68
74 -6
36
27 58
70 -12
144
Students N
Pre-test Post-test
Gain Score D D
2
X Y
X-Y 28
68 60
8 64
29
69 81
-12 144
30 72
85 -13
169
31 68
75 -7
49
32 66
73 -7
49
33 58
76 -18
324
34 55
70 -15
225
35 50
73 -23
529
36 68
63 5
25
37 69
65 4
16
38 50
70 -20
400
39 67
70 -3
9
40 55
73 -18
324
Total 2491
2942 451
7841 Average∑
62.27 73.55
11.275 196.025
Based on the data above, the result of calculation showed that ∑ D = 451 and ∑ D
2
= 7841.
3. Seek Mean from Difference by using formula:
M
D
= D
N
=
40
= 11.275
4. Seek the standard of Deviation from Difference SD
D
by using formula: SD
D
=
D N
2 D
N 2
= 7
841 40
451 40
2
= 196.025
11.275 =
196.025 127.238
= 68.789 = 8.29
5. Seek the standard error from Mean of Difference by using formula:
SE
MD
=
SD
D
N 1
=
. 40 1
=
. 39
=
. 6
.24
= 1.33 6.
Seek t by using formula:
t = M
D
SE
MD
= 11.275
1 .33
= 8.48 The t-score is 8.48 which indicates that there is a difference of degree between
variable X dan Y. Next, after the result of manual calculation was gotten, it rechecked the result
using SPSS – IBM SPSS Statistics Version 20. Paired Samples Test is used to calculate the difference between the pretest and posttest. This analysis can help the
writer to examine the improvement of students’ ability in writing of narrative text. Here are the results:
