Sample is a selected group of subjects for a study where the individuals represent the larger group.
3
The strategy of sampling was Non-probability Sampling; it means that this kind of sampling does not equally give the
opportunity for every population to be selected as the sample.
4
The technique of the sample was total sampling; where all population became the main sample.
The sample of this research was; the A class with 20 students as the experimental class and B class with 20 students as controlled class.
D. Instrument of The Study
The instrument that used for collecting the data was test, exactly a written test. It was divided into two tests, pre-test and post-test. A pre-test was given to
the students before the treatments and post-test was given after treatment. The test was a subjective test which asked the students to write in form of paragraph.
The topic of the writing task was about “ Study at Pesantren”. In pretest the
writer asked students to write at least 150 words into paragraph their arguments and opinions about their best moment when they study at Pesantren, write with
complex, compound and compound complex sentences. The prompt was “Describe your best moment when studying at Pesantren. Write in at least 150
words and make sure you use in complex, compound and compound complex sentences in your writing.” The writer expected students will write text with
complexity and accuracy. While in posttest the writer asked students to write at least 150 words into
paragraph. The topic of the posttest is about sex education for teenager. The prompt was “Describe your opinion about sex education for teenager. Write in at
least 150 words and make sure you use in complex, compound and compound complex sentences in your writing.” Finally the writer will see the students’
grammatical errors and number of subordination in writing.
3
L. R. Gay, Educational Research: Competencies for Analysis and Application, Third Edition, Colombus, Ohio: Merril Publishing Company, 1987,p. 101
4
Sugiyono, Metode Penelitian Pendidikan, Pendekatan Kuantitatif, Kualitatif, dan RD, Bandung: Alfabeta, 2010, p. 117
Validity and Reliability of the Instrument
An instrument which is going to be tested to students should have validity. Heaton defined the validity as
“the extent to which it measures it is supposed to measure”.
5
The test used as the instruments of this research are based on the content of English syllabus, “Memahami makna dalam teks tulis fungsional
pendek dan berbentuk narrative, spoof dan hortatory exposition dalam konteks kehidupan sehari-hari dan untuk mengakses ilmu pengetahuan
”. The students should attain those objectives of learning narrative and hortatory
exposition, therefore, to construct the test or instrument and the objective can be reached, it should be guided on its content and it is known as content
validity. Content validity is a kind of validity that depends on the analysis of the
language which is being tested and the course objective.
6
Before conducting the test, the writer did the consultation to the advisor about the instrument in
order to make it is compatible and appropriate with the syllabus. The instrument of this research has to be appropriate with the objective of learning
writing narrative and hortatory exposition with accuracy and complexity itself, the indicator of learning narrative text and hortatory exposition and instruction
given to students so that there is the appropriateness with the content of the syllabus and the writing material which is tested to the students and the
objective of teaching and learning can be achieved. In addition, to obtain reliability of the instrument the researcher used Sara
Cushing Weigle ’s for complexity and Rod Ellis’s measure for accuracy. Sara
Weigle scored the complexity in writing by counting the number of longer clauses and subordinators, while Rod Ellis scored the accuracy in writing by
calculating the number of grammatical errors per total number of t-units.
5
J.B. Heaton, Writing English Language Test, New York: Longman inc., 1988, p. 159
6
Ibid, p.160