2. Reliability
Reliability refers to the consistency in giving the same tests to the same students or matched students on two different occasions.
10
In order to attain the reliability of the instrument the researcher used an analytic scoring rubric to score
students’ writing pretest and posttest and did inter rater reliabilityto ensure the reliability of the data.
“Inter-rater reliability is an index of consistency across raters calculated using correlations.”
11
Analytic scoring provides more detailed information about test takers performance in different aspect of writing as content, organization, cohesion,
register, vocabulary, grammar or mechanics.
12
The scale of analytic composition is derived by Jacobs et. al. adopted by Sara Cushing Weigle in her book,
Assessing Writing. The primary advantage of an analytic scoring is that it provides more useful diagnostic information about students’ writing ability over a
holistic scoring. The disadvantage of this scoring is time consuming.
Moreover, the researcher also did inter-rater reliability to see the consistency of the data. This step is done to ensure that the rubric used by any scorers is
reliable. So, the researcher conducted inter rater reliability to compare the scoring result by scorer 1 and 2 was not significantly different. It means that the rubric
scoring is consistence. The researcher and the English teacher scored pretest and posttest using the same scoring rubric and in the same time. In case the rater gives
different scores, the mean scores will be provided. Moreover, the researcher should ensure that the perception about what is being assessed between the other
rater and the researcher is should be the same.The table scores can be seen on the
Chapter 4.
10
Ibid.
11
Judy R.Wilkerson and William Steve Lang, Assesing Teacher Competency: Five Standards-Based Steps to Valid Measurement Using the CAATS Model, California: Corwin Press,
2007, p. 243.
12
Sara, op. cit., p. 114.
E. Technique of Data Collecting
After making the instrument, the researcher will collect the data by giving a test to the students. The test technique was one of the data collecting techniques in
aquantitative research.
13
In collecting data, the researcher conducted written test to test students’ writing ability. There was only 1 group of students that being
researched. This group did pretest, 4 meetings of treatment and posttest. Students wrote in personal and gave peer feedback among group member. In the end of the
research, students divided into 2 categories for those ones who were giving elaborated and basic feedback.
1. Pretest
On the first week, the researcher gave explanation about blog such as blog platform, how to create account and how to maintain it. The researcher conducted
pretest on 22
nd
April or the first week of research time. The researcher gave instruction to students to write and give feedback among group member. Students
were divided into 10 groups which is consisted 3 to 4 students. They did written test and gave peer feedback in language laboratory. The next following weeks the
researcher did 4 times treatment on 22
nd
April to 13
th
May 2015. The lesson plan
can be seen on appendix.
2. Postest
On the last week, 20
th
May, the researcher did postest. Posttest is given after the treatment. With the same procedure as pretest, the students were asked to write
and provide feedback on blog platform. After conducting pretest, the researcher and the English teacher d
id score the students’ writing. This way can be referred as inter rater reliability to see the reliability of the instrument. The score describes
in the following chapter.
13
Tim Penyusun Pedoman Penulisan Skripsi FITK, Pedoman Penulisan Skripsi, Jakarta:FITK,2014,p.65.
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