D. Variable
In this research, Power Point media is appointed as the independent variable, the variable influencing other variable, and as the dependent variable was students’
understanding on Passive Voice. Dependent variable is the one which is influenced by the independent variable whether it changes or not. To make clear:
Independent variable X: The Power Point media Dependent variable Y: The students’ understanding on Passive Voice
E. Technique in Collecting Data
1. Test
Technique in collecting data was test. Kind of test was paper and pencil test written test. Hence, this test is a test designed to measure how successful students in
understanding material that have been learned, in short, it is conducted at the end of learning process.
The test given to the subject consists of forty items. It was divided into thirty items for multiple choice and ten items for essay. Each true answer of multiple choice
has two points, so the highest score is 60. For essay, the highest score is 40 with the calculation of each item is four points. Every one point for essay items is given to the
right subject, object, to be, and verb-change. The items of test were taken from several books about grammar.
Related to the research design, the two groups of sample have been measured twice by the pre-rest and post-test. They were grouped into the experimental and
controlled group, and then they got pre-test. Pre-test was carried out to give the information about the characteristics of these two groups. The result of pre-test gave
meaning of checking whether the two groups were similar before being researched. After that, the experimental group has gotten the treatment of this research. And then,
post-test was needed to measure the final result of the groups to get the information of research question.
Before conducting test to the sample, the writer should try out the items of test to another group of students. It was intended to check the eligibility of test items. The
category of good items is interpreted from the value of validity, reliability, index difficulty power, and discriminating power that has been calculated by AnatesV4
software with the basic formula as follows:
2
a. Validity
N : Number of students
X : Score of test items
Y : Total score
After conducting try out, it was found that there was one invalid item, five items is adequate, ten items is significant, and the rest is very significant. The result
of item analysis is described as follows df = 0,304:
Table 3.2 Item Validity of Multiple Choice and Essay
Category Multiple Choice
Essay Very Significant
14 1
Significant 10
5 Adequate
5 4
Insignificant 1
- Source: ANATES V4
Based on the table above, the insignificant item 23 could not be used because the correlational value is really low. For the adequate items, they need to be
checked in depth to know whether the stem or the optional was bad. Then, the errors should be changed before they are going to be used as pre-test and post-test item.
2
Zainal Arifin, Evaluasi Pembelajaran, Bandung: PT REMAJA ROSDAKARYA, 2011, pp. 254—280.
Kategori