25 concludes the problems faced by the teacher and the students in teaching-
learning process. Moreover, the writer is going to use unstructured interview some students about teaching-learning vocabulary after and
before using games. In here, the writer takes 10 samples of 49 forty-nine students.
c. Test
The test used in this study is pre-test and post-test. The pre-test is done before using games. It is to measure students’ vocabulary firstly. Then, the
post-test is implemented after using games. In this study, the test is done in multiple choices form, and the test is held on the third action of each
cycle.
H. Technique of the Data Analysis
The analysis qualitative data used in this study is the observation of students’ activities during teaching learning process, and the interview before and after CAR.
Then, in analysis the quantitave data, the writer took the average of students’ vocabulary score in one cycle. It is used to measure how well students’ ability on
vocabulary. It uses the formula:
6
_ ∑ x
X = ── n
_
X : mean x : individual score
n : number of students To know the class percentage, the writer used the formula:
F P = ── X 100
N
6
Anas Sudijono, Pengantar Statistik Pendidikan, Jakarta, Raja Grafindo Persada, p. 80
26 P : the class percentage
f : total percentage score N : number of students
After getting mean of students’ score per actions, the writer analyzed whether there are any improvement of students’ vocabulary score from pre-test up to students’
average score in cycle 1 and cycle 2 or not. In analyzing that, the writer uses the formula:
y - y1 P = ─ ─ ─
X 100 y
P : percentage of students’ improvement y : pre-test result
y1 : post-test 1
y2 - y P = ─ ─ ─
X 100 y
P : percentage of students’ improvement y : pre-test result
y2 : post-test 2
I. Data Validity
Validity is the component criteria for evaluating the test or as a measure of the test. Validity in action research, the writer took Charles Alderson, Caroline Clapham
and Dianne wall’s criteria that mention the validity of action research including
27 rational or content, empirical, and construct validity.
7
In this study, the writer is only uses empirical validity.
Empirical validity depends empirical or statistical evidence as to whether the student’ marks on the test are similar to their marks on other appropriate measures of
their ability, such as their score. It means that validity in action research, validity could be seen from the result of the test post test. When the result of test in cycle
two is better than the result of test in cycle one, it means that the test is successful.
J. The Trustworthiness of Study
