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second part consisted of two items. In this part, the students were required to analyse two adjective clauses by applying concepts and theories of the X schema
and adjective clauses in the form of tree diagrams. The test should be finished in forty-five minutes. In order to elicit the students’ performance and to get reliable
data and measurement to be analysed, the test should meet some criteria. Those are validity, reliability and practicality.
2. Validity and Reliability of the Instrument
In order to elicit the performance of the students, the writer composed a test as the instrument. As a research instrument, a test should meet certain criteria
so that the data obtained really provided the intended information that the researcher wanted to know. Ary, Jacob and Razavieh 2002: 256 state that a
research always depends on the measurement. In this case, there are two important characteristics that every measuring instruments should possess, namely test
validity and test reliability. The following is the further discussion about the validity and the reliability of the test used in this research.
a. Test Validity
Validity refers to the extend to which an instrument measures what it is intended to measure Ary et al., 2002: 256. Similarly, Hughes 1989: 22 state
that a test is said to be valid if it measures accurately what it is intended to measure. In order to conduct a valid test, the agreement between what is intended
to measure and the result of measurement should be achieved. PLAGIAT MERUPAKAN TINDAKAN TIDAK TERPUJI
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In addition, Hughes 1989:22 states that the concept of validity reveals a number of aspects. They are content validity, criterion-related validity, construct
validity and face validity. To construct a test which meets all these aspects is a difficult task. A test may only have some of the aspects, but it does not mean that
the test is not valid at all. In this research, the test composed did not have all the aspects above, since it only included three of the aspects: content validity,
construct validity and face validity.
1 Content Validity
According to Hughes 1989: 22, a test is said to have content validity if its contents constitute a representative sample of the language skills, grammars,
vocabularies or other elements with which they are meant to be concerned. The test will have content validity if it includes a proper sample of the relevant
structures which depend on the purpose of the test. Considering that this reserach was intended to investigate the students’ performance on analysing adjective
clause using the X schema, the test which was composed by the writer met the content validity because the test contained proper sample of items on the adjective
clause and the X schema. There were some important concepts and theories related to the adjective
clauses in the light of the X schema as taken from O’Grady et al. 2005: 151- 186. They were main clause, dependent clause, modifier, head, I, inflection
phrase, complementizer phrase, Wh movement, trace and tree diagram. Table 3.1 shows the distributions of the concepts and theories of the test.
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Table 3.1 The Distribution of the Test Contents
PART A Number
Concepts and Theories
1 dependent clause and main clause
2 dependent clause, main clause, modifier, and relative pronoun
3 dependent clause, main clause and relative pronoun
4 merger, I, inflection phrase, complement and
complementizer phrase 5
complement, complemetizer phrase and Wh movement 6
complement, complemetizer phrase and Wh movement 7
tree diagram, relative pronoun, complement, complementizer phrase, Wh movement and trace
8 main clause, merge operations, I, inflection phrase and head
9 tree diagram, relative pronoun, complement, complementizer phrase,
Wh movement and trace 10
tree diagram, modifier, complement and complementizer phrase
PART B
1 subject-subject adjective clause testing about merge operations, I,
inflection phrase, complement, complementizer phrase, Wh movement and trace
2 object-subject adjective clause testing about merge operations, I,
inflection phrase, complement, complementizer phrase, Wh movement and trace
The test met the requirement of content validity because it is clear that all of the concepts and theories of the adjective clauses and the X schema were present.
The concepts and theories were also presented in the linear order or from the easiest to the most difficult.
2 Construct Validity
The test met the construct validity requirements because the score which yielded from the test measured the students construct, especially in the area of
adjective clause and the X schema. Construct such as main clause, dependent clause, merger, movement operation and tree diagram existed on the test. It is in
line with the purpose of the test which is intended to know the performance of the PLAGIAT MERUPAKAN TINDAKAN TIDAK TERPUJI
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sixth semester students of the English Language Education Study Program of Sanata Dharma University on analysing the adjective clauses using the X schema.
Hughes 1989: 26 and Brown 2001: 389 underlie those arguments. Furthermore, Bachman and Palmer 1996: 21 explain that the term construct
validity is therefore used to refer to the extent to which we can interpret a given test score as an indicator of the abilities or construct. The score of the test would
show the students’ performance on the related subject of the test.
3 Face Validity
According to Mousavi 2002: 244 as quoted by Brown 2004: 26-27, face validity refers to the degree to which a test looks right and appears to
measure, based on the subjective judgment of the examinees who take it, the administrative personnel who decide on its use, and other psychometrically
unsophisticated observers. Brown adds that face validity is not something that can be empirically tested by a teacher or even by a testing expert. Therefore, to elicit
the face validity the writer had asked the supervisor and the lecturer who teach Morpho-Syntax to give feedback before the test was administrated. According to
their opinion, the test had met the requirements to be used in the research.
b. Test Reliability
