Table 3.1 Index of Difficulty
ID
VE = Very Easy 0.80
ME = Moderately Easy 0.71 - 0.80
MeDi = Medium Difficult 0.51 - 0.70
MoDi = Moderately Difficult 0.31 - 0.50
VeDi = Very Difficult 0.00 - 0.30
Table 3.2
Discriminating Power
DP
E = Excellent 1.0 - 0.40
G = Good 0.30 - 0.39
M = Mediocre 0.20 - 0.29
P = Poor 0.00 - 0.19
W= Worst -0.01
After the the calculation of this test, there were only 16 numbers of questions which were valid to be used as the pre-test and post-test of this research.
In order to make the questions easier to be calculated, 9 invalid questions were revised. There are 25 questions eliminated from this test. So, the final pre-test and
post-test used in this research was a test that consisted of 25 numbers of multiple choice about narrative text.
F. Technique of Data Collection
In collecting the data, the writer used experimental and controlled class. The instruments that were used to collect the data are:
a. Pre-test The writer gave pre-test to both class; experimental and controlled class. The
students were given some questions in the form of multiple choice based on the English text provided. The students should read the text by themselves without
using any dictionary or discussing with friends. There will be 25 numbers of multiple choice question.
b. Post-test Post-test was used to find out if jigsaw technique is effective towards
students‟ reading comprehension. The purpose of conducting the post-test is to find out the result of students‟ achievement after the students have been given the
treatment in the form of teaching. The question test of post-test used was same as the question test used in pre-test which consists of 25 numbers of multiple choice
question.
G. Technique of Data Analysis
The next step of the research were processing and analyzing the data. The analysis was done to the scores between experimental and controlled class.
To find out the differences of students‟ scores by using the different method, the technique of data analysis that was used in this research is statistical analysis with
t-test, it is used to test the significance of the mean gained score of the experimental group and the controlled group. The formula of T-test was expressed
as follows:
2
M
1
= Mean of Variable X M
2
= Mean of variable Y SE = Standard Error
In order to get the calculation of T-test, there are several steps to be taken, they are as follows:
1. Determining Mean of variable X, with formula:
∑
2
Anas Sudijono, Pengantar Statistik Pendidikan, Jakarta: PT. Raja Grafindo Persada, 2006, p. 314.
2. Determining Mean of variable Y, with formula:
∑
3. Determining Standard of Deviation Score of Variable X, with formula:
√∑
4. Determining Standard of Deviation Score of Variable Y, with formula:
√∑
5. Determining Standard Error Mean of Variable X, with formula:
√
6. Determining Standard Error Mean of Variable Y, with formula:
√
7. Determining Standard Error of different Mean of Variable X and Mean of Variable Y, with formula:
√
8. Determining t
o
with formula:
9. Determining Degrees of Freedom df, with formula:
H. Hypothesis of the Research
