41
D. Instrument of the study
The instrument of this research was vocabulary test which consisting of 40 fourty questions. The test was diveded into two test form; they were multiple
choices and matching test. They are divided into three categories; easy 30, middle 60, and difficult 10. Multiple choices consist of 20 items from
number 1 to number 20. It’s score per item is 4. It means if the students can choose the answer of 1 item correctly, they will get 80 scores.
Matching test consist of 20 items from number 20 to number 4 0. It’s score
per item is 2. It means if the students can choose the answer of 1 item correctly. They will get 2 score and if they can choose the answer of 10 items correctly, they
will gate 20 scores. Before the test was used for gathering the data was be tested.
E. Method of Data Collecting
Collecting data was an important thing in this research that can be determined. There were two times, namely used pre-test and post-test to collect
the data: 1.Pre-test
The pre-test is given in the beginning of attending class pre-test is given the writer doing the experiment to know the students knowledge of the material
that will be thought. The instrument consists of 40 items test consisting of two types:
a. Multiple choice, there are 20 items and each item is scored 3, so the total
score of this type is 60. b.
Completing, there are 20 questions and each item is scored 2, so the total score of this type is 40.
2.Post-test The writer gives the post-
test after the lesson finished to know the students’ ability in mastering just thought. The instrument consists of 30 items test
consisting of two types: a.
Multiple choice, there are 20 items and each item is scored 3, so the total score of this type is 60.
42
b. Completing, there are 20 questions and each item is scored 2, so the total
score of this type is 40.
F. Method of Data Analysis
Data analysis is the last step in the procedure of experiment, in this case, processing the data. The data processing is the step to know the result of both the
experimental class and the controlled class and also their differences. To find out the differences of student’s score in using the Direct Method in
teaching vocabulary, the writer uses t-test The writer used the comparative technique. The comparative technique is an
analysis technique to evaluate hypothesis concerning the differences between two variables examined statically.
In the comparative technique, the variables are compared to recognize whether or not the differences are significant. The writer used t-test formula that
adapted from Sudjiono Before using t-test formula; the writer has sought some formula below.
1
a. Determining Mean with formula:
M
1
= M
1
+ ί
N FX
M
1
= the average of variables score ∑ fX′ = sum of frequency multiply the student’s score
N = number of students
b. Determining standard deviation score with formula:
SD
I
= ί
2 2
N fx
N fx
SD
I
= standard deviation of gained score X ∑ fix′
2
= sum of squared gained score ∑ fix′
= sum of gained score N
= number of students
1
Anas Sudijono. Pengantar Statistik Pendidikan, Jakarta: PT Grafindo Persada, 2008, p. 318