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2 From 50 items of the test of reading comprehension, 20 items are valid and
30 items are not valid.
b. Reliability
Nunan 1992:14 says that reliability refers to the consistency and of the results obtained from a piece of research. Sugiyono 2006,states that
reliability refers to the level of internal consistency or stability of the test over time.
To verify the reliability of the test, the writer uses the Alpha Cronbach formula.
Based on the analysis using the formula above, the result of reliability coefficientof the test of vocabulary mastery and the test of reading
comprehension are 0.817 and 0.853. it can be said that the instrument are reliable. The computation of reliability test of the two variables can be seen
at Appendices 16 and 18.
E. Data Analysis Technique
As stated above, this research tends to know the contribution of the independent variable to the dependent variable. In order to achieve that
purpose, it must be known from the relationship of the variables. The research tests the hypothesis using Product Moment and Multiple Linear regression
formula. According to Borg and Gall in SuharsimiArikunto, 2002:251, Product Moment is used to describe the strength of relationship between two
variables, while Multiple Linear regression is used to describe the strength between one independent variable and one dependent variable. In this
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research, the writer tends to use computerized calculation by utilizing SPSS 16.
1. Pre-requirement test
There are major prerequisite tests for the data to enter linear regression analysis:
a. Normality Test
Normality test is one of the prerequisite tests before entering linear regression analysis, that is used to know whether the dependent variables are
normally distributed or not. To check the normalitytest of the dependent variable, it can be done by using SPSS 16. The normality can be seen from
p
significance on Lilliefors test. If
p
significance value is greater than 0.05
p
0.05, it tells that the distribution of the data is normal.
b. The Linearity of Regression and the Significance of Regression
The Linearity test is aimed to know whether two variables have significant linear regression or not. This test becomes the major prerequisite for the data
to entering linear regression analysis. In SPSS, the linearity can be known by using Anova
Test for Linearity
on the significance value
p
= 0.05. Two variables can be linear if
p
0.05.
2. Hypothesis Test
The study was conducted to test the hypothesis. To test the hypothesis, the writer usedthe Simple Linear Regression analysis. The statistical hypothesis
can be determined as follows:
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