46

CHAPTER IIIRESERCH METHODOLODY

3.1 Research Design This is a quantitative research. This research will be incorrelationalresearch design. The correlational study is meant to find the relationships between two or more variables (Arikunto, 1998: 326). Furthermore, Ary (1985:118) states that correlational procedures show the extent to which change in one variable is assosiated with change in another variable. There are two kinds of variables, namely: independent and dependent variable. Ary states that variable is an attributive that is regarded as reflecting or expressing some concept or construct (1985: 30). Moreover, he states that the dependent variable is the phenomenon that is the object of study and investigation. The independent variable is the factor that is measurably separate and distinct from the dependent variable, but may relate to the dependent variable. In this research reading habit is the first independent variable (X1), vocabulary mastery is the second independent variable (X2), and reading comprehension is the dependent variable (Y).Figure 3.1 The Relationship between X1 and Y, X2 and Y, and X1 and X2 toward Y

Reading Habit(X1)

Reading Comprehension(Y)

Vocabulary Mastery(X2)

3.2 Population and SampleA population is the group to which the results of the study are intended to apply (Fraenkel and Wallen, 1993: 78). According to Creswell (2008: 151), population is a group of individuals who have the same characteristics.In this research the population is all the students of MAN 1 Surakarta, in XI Science classes (XI IPA 1, XI IPA 2, IPA 3, IPA 4) in the academic year 2011/2012.Table 3.1 The Total of Students of XI Science ClassNoClassTotal (students)

1.XI IPA 116

2.XI IPA 222

3.XI IPA 324

4.XI IPA 433

95

Source: Doc. MAN 1 Surakarta. 2011/2012A sample is a subgroup of the target population that the researcher plans to study for generalizing about the target population (Creswell, 2008:152). Fraenkel and Wallen (1993: 78) state that a sample is a group in a research study on which information is obtained. To determine the size of sample, based on Suharsimi (2006: 134), only for estimation, so if the subject less than 100, it would be better if we take all the subjects. Therefore, the research is a population research. However, if the total of the subject is big, we can take around 10-15% or 20-25% or more. This research uses the sample from all of the total of population. It is based on the total of students in the science class of XI in MAN 1 Surakarta in the academic year of 2011/2012, those are 95 students from four classes.Further, the researcher took 34 students randomly to be the sample of try-out and 56 students to be the sample of research. However, 5 students did not attend when the researcher held the research. The researcher uses simple random sampling to take the sample. So, every student of the eleventh grade science classes has an equal and independent chance of being included in the sample. The steps of choosing the sample as follows:1. Making a list of 90 students2. Giving each student a code3. Writing each code on a piece of paper and enrolling them4. Filling the rolled papers in the box5. Taking the rolled papers in the box randomly and the result will e the sample of try-out, it was repeated 34 times6. The rest of rolled papers in the box will be the sample of research (56 students)3.3 Techniques of Collecting DataThe writer uses test and questionnaire as the techniques to collect the data for research. The test is used to collect the data of students vocabulary mastery and reading comprehension whereas the questionnaire will be used to obtain the data of students reading habit. The instruments of collecting data are:3.3.1 The instrumentsa. TestA test is a set of stimuly presented to an individual in order to elicit responses on the basis of which a numerical score can be assigned (Ary, 1985: 189). While according to Suharsimi, test is a sequence of quenstions or exercises or other devices to measure skill, knowledge, intelligence, ability or talents person which has by people or group (1998: 139).The test of vocabulary mastery is intended to collect data about students vocabulary mastery. The test is an objective test in the form of multiple choice type consisting of 30 items. There are five options (A, B, C, D, E) in each item, and the students are required to choose the correct answer by crossing one of the five letters provided in the answer sheet.The reading comprehension test is intended to collect data about students reading comprehension. The test is an objective test in the form of multiple choice type consisting of 30 items. There are five options (A, B, C, D, E) in each item, and the students are required to choose the correct answer by crossing one of the five letters provided in the answersheet.The way to score the answer is if the answer is correct, it is scored 1; however, if the answer is incorrect, it is scored 0.b. QuestionnaireQuestionnaire is a list of questions which are distributed via pos to fill out and to return it back or it can be answered under researcher countrol (Nasution, 2003: 128). According to Suhasimi, questionnaire is a set of questions which are given to other people in order to willing give a response based on researcher required (1998: 136). In this study, the questionnaire is given to the students to find numerical data of their reading habit. The questionnaire consists of 30 items and each item has five options (A, B, C, D, E) with the scale of scoring from 1 to 5. The students are required to choose one of them based on what the students actually experienced. If it has not happened, it is also an actual response of the students toward the situation given in the questionnaire.Likert scale is used to measure attitude, opinion, peoples or groups perception about social phenomenon. The way to score the questionnaire is as follows:Table 3.2 Category Score of Likert ScaleStatement

OptionABCDE

Positive54321

Negative12345

3.3.2 Validity and ReliabilityBefore the instrument is used, there is a try-out. It is intended to find the validity and reliability of instrument. The instruments of this research: reading habit questionnaire, vocabulary mastery test and reading comprehension test is given to the students joining the try-out. To know the validity and reliability, the researcher is assisted by SPSS 16.0 program for Windows.a. The validity of the instrumentAn instrument is valid if it is able to measure what the researchers are going to measure (Nasution, 2003: 74). To measure the validity of reading habit questionnaire, vocabulary mastery test, and reading comprehension test, it is used Pearson Product Moment. The formula is as follows:

(Suharsimi Arikunto, 2006: 274)rxy= the correlation coefficient between X and YN= the number of the studentsX= the score of each itemY= the score of each student The result of the try out indicates that:1. From 30 items of reading habit questionnaire, 29 items are valid and 1 item is invalid.2. From 30 items of vocabulary mastery test, 18 items are valid and 12 items are invalid.3. From 30 items of reading comprehension test, 19 items are valid and 11 items are invalid.b. The reliability of the instrumentReliability refers to the consistency of the scores obtained-how consistent they are for each individual from one administration of an instrument to another and from one set of items to another (Fraenkel and Wallen, 1993: 146). According to Ary (1985: 225), the reliability of a measuring instrument is the degree of consistency with which it measures whatever it is measuring.To determine the reliability of reading habit questionnaire, vocabulary mastery test, and reading comprehension test, it is used Alpha Cronbach technique because it has a flexibility to measure a scale which has characteristic dichotomy and non dichotomy. The formula is as follows:

(Suharsimi Arikunto, 2006: 196)r11 = the coefficient of reliabilityk = the number of itemsS12 = the total variance of each itemSt2= the total varianceThe computation shows that the coefficient of reliability of reading habit is 0.918. While, the coefficient of vocabulary mastery is 0.780 and the coefficient reading comprehension is 0.778. 3.4 Techniques of Analizing DataThis research is to test the hypothesis using Product Moment and Multiple Linear Regression. Product Moment is used to describe the strength of relationship between two variables, while Multiple Linear Regression is used to describe the strength of the relationship between several indendent variables and one dependent variable (Borg and Gall in Suharsimi Arikunto, 1998: 253). To analyse all the hypothesis, the researcher is assisted by SPSS 16.0 program for Windows.To test the first hypothesis where it says; there is a positive significant correlation between reading habit and reading comprehension, and the second hypothesis; there is a positive significant correlation between vocabulary mastery and reading comprehension, Pearson Product Moment used. The formula is:

To test the third hypothesis; there is a positive significant correlation between reading habit, vocabulary master, and reading comprehension, multiple linear regression is used as the technique. The formula is:

Y = a + b1 X1 + b2 X2 + .... + bn Xn.

Y= dependent variablea= constantb= coefficient regression each independent variableTo find out the contribution of each predictor (independent variables) to the dependent variable, the researcher uses coefficient of determination.