1. Pre-test
The writer held the pre-test at the first meeting. Before the students learnt reading descriptive text through collaborative learning, she gave
them a pre-test measuring the dependent variable. 2.
Post-test The writer gave the post-test after the treatment had been given by
collaborative learning towards students’ ability in reading descriptive text. This test for measuring the dependent variable again.
Before administering the test, the writer tried the pre-test instrument to another class. She wanted to analyze the validity and the reliability of pre-test
instrument in order to check whether it had been good or not to be used. She used software ANATEST to calculate both validity and reliability of the pre-test
instrument. The pre-test instrument consisted of 30 questions of multiple choices. The writer just took 20 questions were valid and reliable.
Based on the results of validity and reliability at the seventh grade students of SMP Pelita Harapan which used software ANATEST, there were 26 questions
were valid and reliable from 30 questions. The questions were valid and reliable: 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 20, 21, 22, 24, 25, 26, 28,
29, and 30. Meanwhile, the questions were not valid and reliable: 3, 13, 23, and 27.
For the details of ANATEST’s calculation, it can be seen in appendix 10.
F. The Technique of Data Analysis
The data was obtained from the tests used to know how effective collaborative learning towards students’ ability in reading descriptive text. It was
gained from the students’ pre-test and post-test scores.
To find out the effectiveness of using collaborative learning towards students’ ability in reading descriptive text, the writer used t-test formula which
was adapted from Anas Sudijono. Before using t-test formula, the writer had to seek some formulas below.
4
4
Anas Sudijono, Pengantar Statistik Pendidikan, Jakarta: Raja Grafindo Persada, 2008, p. 305-307.
a. Determining mean of variables
M
D
=
Ʃ
M
D
= the average of gained score mean of difference Ʃ D
= sum of gained score N
= number of students b.
Determining of standard deviation score of variables SD
D
= √
2
SD
D
= standard deviation of gained score D
2
= sum of squared gained score Ʃ D
= sum of gained score N
= number of students c.
Determining of standard error mean of variables SE
MD
=
√
SE
MD
= standard error mean of gained score SD
D
= standard deviation of gained score N
= number of students d.
Determining t t
= t
= t observation M
D
= the average of gained score mean of differences SE
MD
= standard error mean of gained score e.
Determining degrees of freedom df
= N-1 df
= degree of freedom N
= number of students
G. The Statistical Hypothesis
The statistical hypothesis is to probability in term of sampling and measurement error. It is stated in either the null or alternative hypotheses. Null
hypothesis states that there is no difference between the population means of the two groups. It is indicated by the symbol H
. Meanwhile, alternative hypothesis which is designed as H
a
is the opposite of null hypothesis. The writer proposes alternative hypothesis and null hypothesis as below:
1. If t
observe
t
table
, the alternative hypothesis H
a
is accepted and the null hypothesis H
is rejected. It means that there is an effectiveness of Collaborative Learning in improving
students’ reading ability between pre-test and post-test scores.
2. If t
observe
t
table
, the alternative hypothesis H
a
is rejected and the null hypothesis H
is accepted. It means that there is no effectiveness of Collaborative Learning in improving
students’ reading ability between pre-test and post-test scores.
