REVIEW OF RELATED LITERATURE
C. Research Instruments
The instruments used to gather the data in this study were a test and a questionnaire. Hague (1995: 2) mentioned the four objectives of questionnaire.
“First, it is used to obtain the accurate information from the respondent. Second, it gives the design in interview. Third, it gives the standard format of fact, comment, and attitude recording. The last is to ease the data processing.”
The questionnaire used as the instrument in this research consisted two parts. The first part was thirty items of close-ended responses. In this part, the participants were required to choose the number which showed their opinion on the statements given. The second part was one item of open-ended response. In this part, the participants were required to answer the question based on their own opinion with explanations on their opinion and suggestions. Those questions were related to the possible factors causing errors.
The questionnaire was made by investigating five elements, such as students’ perceptions, abilities, motivations, teaching learning activities and also time and social influences. Ellis (1997: 4) identified two factors influencing the
26 language learners in learning second language such as internal and external factors. Therefore, the writer divided those five elements into two, which are internal and external factors. Ellis also gives the examples of each factor. Social conditions and input are external factors. On the other hand, Ellis (1997: 4-5) classified the cognitive mechanism and knowledge into the internal factors. Based on that theory, the writer classified those five elements such as: internal factors, which included the students’ perceptions, abilities, and motivations, and external factors, which included teaching learning activities and time and social influences.
On the other hand, the writer also used the test to gather the data. A test is
“a method to measure the students’ ability or knowledge and it also can provide the information about the achievement of group of learners” (Hughes, 1989: 4).
The test was arranged to measure the students’ understanding on conditional sentence. Therefore, the test was essential part of the research. Based on those facts, the writer chose a test and questionnaire as the instruments to gather the data.
The test consisted of thirty items and it was divided into two parts. The first part consisted of fifteen items. In this part, the students were required to fill in the blanks with the correct answers based on the rule in conditional sentences.
The objective of this part was that the students were able to recognize which type of conditional sentences used in the questions and demonstrate the correct pattern of conditional sentences. This would “show the participants’ ability to recognize the grammatical functions of words in sentences structures” (Freeman and Long, 1991: 167). The second part consisted of fifteen items. In this part, the students
were required to make the conditional sentences based on the given facts. The objective of this part was that the students were able to recognize the correlation between the fact and the conditional sentences and demonstrate the correct pattern of conditional sentences based on the given facts. This kind of test “provided a better indication of students’ real achievements in learning” (Ebel, 1979: 96).
Because of its essential role in the research, the test should meet the requirements of measurement. Those are validity and reliability.
1. Validity
Validity is one of the important things in constructing the test. A test is said to be valid if “it measures accurately what it is intended to measure”
(Hughes, 1989: 22). There are four types of validity in test. Those are:
a. Content Validity
A test is said to have content validity if its content constitutes as representative sample of the language skills, structures, and so on with which it is meant to be concerned. The test would have content validity only if it included a proper sample of relevant structures. Therefore, in order to have high content validity, the test should contain the items which are intended to be measured on the test. The importances of content validity are: “first, the greater a test’s content validity, the more likely it is to be an accurate measure of what it is supposed to measure. Second, such a test is likely to have a harmful backwash effect”
(Hughes, 1989: 22-23). The details of the content of the test are presented in the Appendix 2.
28 The table in the Appendix 2 shows the content of the test. It is clear that all the types of conditional sentences were present in the test. Therefore, it could be concluded that the test fulfilled the content validity.
b. Construct Validity
A test, a part of a test, or a testing technique is said to have construct validity if “it can be demonstrated that it measures just the ability which it is supposed to measure. The word ‘construct’ refers to any underlying ability (or trait) which is hypothesize, for example, that the ability to read involves a number of sub-abilities, such as the ability to guess the meaning of unknown words from the context in which they are met” (Hughes, 1989: 26). The test, which was used as the instrument, required the students’ ability on recognizing and making a good conditional sentence for each item. Therefore, the test can be concluded that it fulfilled the construct validity.
c. Face Validity
A test is said to have face validity if it looks as if it measures what it is supposed to measure. “Face validity is hardly a scientific concept, yet it is very important. A test which does not have face validity may not be accepted by candidates, teachers, education authorities or employers” (Hughes, 1989: 27).
Best (1981: 153) says that in research, validity is “that quality of a data gathering instrument or procedure that enables it to determine what it was designed to determine.” In this case, the writer showed the format of the test and the questionnaire to her sponsor and asked for her comment about the format of the
test and the questionnaire. The test and the questionnaire are separated in different page but they were bundled together.
2. Reliability
According to Brown (2004: 20), “a reliable test is consistent and dependable.” It means that the results of the test, which was administered to two different groups, should be more or less similar. In research, reliability is “the quality of consistency that the instrument or procedure demonstrates over a period of time” (Best, 1981: 154).
To calculate the reliability of the whole test was the writer used K-R 20 formula because this formula is used to determine the homogeneity which is based on the proportion of correct and incorrect responses (Ary et al., 2002: 258). The test also scored based on the correct and incorrect responses, therefore the writer chose this formula. The formula is as follows.
rxx=
sx2= variance of the total scores (squared standard deviation) p =proportion of correct responses on a single item
q = proportion of incorrect responses on the same item
30 In order to know whether the test was reliable or not, the writer used the table of the value of reliability coefficient. The classification is presented in Table 3.1.
Table 3.1: The Classification of Reliability Coefficient (Best, 1981: 255)
Coefficient (r) Relationship
0.00 to 0.20 Negligible
0.20 to 0.40 Low
0.40 to 0.60 Moderate
0.60 to 0.80 Substantial
0.80 to 1.0 High to very high
Before the real test was administered, the researcher administered the pilot test to the two classes of the fifth semester students of the English Language Education Study Program in Structure V class. The result of the pilot test showed that the reliability coefficient was 0.86. Based on the classification of the reliability coefficient, this result indicates that the test had high reliability.