2. Administering posttest
The posttest was conducted to know the students’ improvement of vocabulary after the treatments were given. Similar to the pretest, the researcher used 30
items in the test.
3.5. Research Procedures
1. Determining the sample of the research
The sample of the research was selected by using random sampling technique, which was using lottery. The researcher takes one of six classes of
the second year students at SMP Muhammadiyah 3 Bandar Lampung as the research sample.
2. Selecting instrument material
In this research, there was one pretest that was proper to the grade VIII students of Junior High School. It focused on vocabulary, which is classified
into content words noun, verb and adjective. The materials were taken from student book and teacher-made materials based on School Base Curriculum.
3. Conducting the try out
This test was aimed at finding out the quality of the test which would be used as the instrument of the research, and determined which item should be
revised for the pretest and posttest. 4.
Conducting the pretest It has been conducted before the treatment. It was held to measure the ability
of the students before the students get the treatment.
5. Conducting the treatment
After giving pretest, the students were given three times treatment by using STAD technique based on the lesson plan which had been prepared.
6. Conducting the posttest
The posttest was administered after the application of STAD technique. The aim is to find out the students’ vocabulary achievement after the
implementation of STAD technique. 7.
Analyzing the test result After conducting pretest and posttest the researcher analyzed the data. The
data was computed through Statistical Package for Social Science SPSS version 17. The researcher then analyzed the students’ score from pretest and
posttest then make a discussion about the result. 8.
Reporting the result In reporting the data, the data was arranged systematically based on the
pretest and posttest to see whether there is an increase on the students’ vocabulary achievement.
3.6. Criteria of Good Test
In this research, to prove whether the test have a good quality or not, it has to be tried first. Try out is the test to measure the quality of the research instrument. The
test can be said had good quality if it has a good validity, reliability, level of difficulty and discrimination of power.
