26
the population used as the sample. If the population is homogenous enough and the number of the population is less than 100, we can take about 20-25.
I chose class IIIA as a sample to be the representative of the population because these students have represented the whole population. The numbers of the
students of the class concerned were forty-one students.
3.4 Variables
A variable is a characteristic that takes on different values or conditions for different individuals Wiersma, 1991:25. There are two variables in this study.
Those variables are: a.
Reading comprehension ability as an independent variable, and b.
Students’ national state exam result a dependent variable.
3.5 The Instrument
An instrument plays an important role in a research. Heaton 1975:1 says that test may be constructed primarily as device to reinforce learning and to
motivate the students or primarily as a means of assessing the students’ performance in the language.
3.6 Try-Out
The instrument was tried out before being given to the chosen sample. In this research, try-out was conducted for 38 students in class III B on Tuesday,
April 5
th
, 2005.
27
3.7 Procedure of Analyzing Data
3.7.1 Validity of the Test
I used content validity I wanted to measure the students’ reading comprehension ability. In line with the issue, Moore 1983:212 asserts that
content validity is most useful with intelligence, ability, achievement and skill, and proficiency test.
Ary 2004:296 as quoted by Furchan states that the researcher should compose the test, which is used as an instrument in the research, by consulting to
the experts in order for the test or the instrument to be valid. I took the following considerations before constructing the items of reading
comprehension test. 1.
Consulting the GBPP Basic Course Outline in selecting the items to be tested in the research. The test items involved the materials of reading
comprehension related to those mentioned in the Basic Course Outline. 2.
Consulting the first and second adviser before constructing the test items. 3.
Choosing the appropriate topics of the passages based on the curriculum used in order for the instrument to cover all the reading material items taught in the
third-grade of junior high schools. Besides using content validity, I used empirical validity by administering
try-out in my research. To find out the validity, I used this formula:
{ }
{ }
2 2
2 2
.
∑ ∑
∑ ∑
∑ ∑
∑
− −
− =
y y
N x
x N
y x
xy N
r
xy
Arikunto, 2002:
146
28
in which: r
xy
= correlation coefficient N = number of students
x = total of item score y = total of the score
3.7.2 Reliability of the Test
Heaton 1984:155 says that reliability is also an essential characteristic of a good test. Meanwhile, Gay and Dielhi as quoted by Sigit 2003:146 define that
reliability is the ability to measure without any mistakes and the result will always be consistence although the test is used by other people in different places. Gay
and Dielhi say that reliability means consistency, dependability and trustworthiness.
Reliability has to do with the result. It means that the examinee will always find approximately the same result if the same test is given to the same examinee
in different occasions, different places and if the answer sheets are graded by different people.
Reliability can be measured by using K-R 21 formula as folows:
⎟ ⎠
⎞ ⎜
⎝ ⎛ −
⎟ ⎠
⎞ ⎜
⎝ ⎛
= kVt
M -
k M
1 1
- k
k r
11
Arikunto, 2002:164
in which:
29
n Y
M n
n Y
Y V
2 2
t
Σ =
Σ −
Σ =
in which: r
11
: instrument reliability k
: total item to be tested M
: total score average Vt
: total varians Y
: total score n
: number of students
3.7.3 Level of Difficulty
The difficulty index or the facility value of an item shows how easy or difficult the item proved in the test. Analysis of difficulty level is intended to
select the items that have a good level of difficulty. An item is said to have a good level of difficulty if it is not too easy or too difficult. This formula was used to
compute the value of level of difficulty:
Js B
P =
Arikunto, 2005:208
in which:
P = the level of difficulty B = the number of students who answered correctly
30
JS = the total number of the students
3.7.4 Discriminating Power
Analysis of discriminating power is important to distinguish the high and low achievers. Heaton 1975:157 states that the discrimination of the test is its
capacity to discriminate among the different candidates and to reflect the differences in the performance of the individuals in the group.
The discriminating power of the items was measured by using this formula:
B B
A A
J B
J B
D −
=
Arikunto, 2005:213
in which: D = the discrimination index
B
B
A
= the number of students in upper group who answered the item correctly B
B
B
= the number of students in lower group who answered the item correctly J
A
= the number of students in upper group J
B
= the number of students in lower group
3.8 Correlation Analysis 3.8.1 Product Moment Correlation
This study involved two variables. Those two variables were reading comprehension ability as an independent variable and students’ national state
exam result as a dependent variable. This study estimated the students’ success in
31
English. According to the Standard Operational Procedure from the National Education Department, this success was realized by their achievement with the
score of at least 4.26 four point twenty six in their national state exam. I assumed that if the students’ comprehension towards passages in English was
good, they would be successful in their test. This assumption was based on the fact that the majority of the test items were dominated by passages or texts.
The estimation above was proved by using the formula called Product Moment Correlation, which studied the relationship between these two variables. I
used this formula to calculate the relationship of X that represented the students’ reading comprehension ability to Y that represented the students’ final
achievement, which was symbolized by r.
{ }
{ }
2 2
2 2
.
∑ ∑
∑ ∑
∑ ∑
∑
− −
− =
y y
N x
x N
y x
xy N
r
xy
Arikunto, 2002:146 in which:
r
xy
= correlation coefficient N= the number of students
x = independent variable score y= dependent variable score
If r
xy
r
tabel
meant that the hypothesis, stating that there was a relationship between reading comprehension ability and students’ national state exam result,
could be accepted.
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CHAPTER IV
DATA INTERPRETATION
Reading comprehension, which is one skill of the four language skills in English, is regarded as a significant skill that should be mastered by those who
learn English. In my opinion, secondary students need to master this skill, considering reading comprehension is one of the skills tested in the national state
exam. I assume that the students’ reading comprehension ability could influence their achievement in the final examination.
Regarding the importance of mastering reading comprehension, I conducted a test for I wanted to know the extent to which students’ master reading
comprehension and if there is a correlation between their comprehension ability with their achievement in doing their test.
To answer those two questions, I conducted research to prove my assumption that there is a correlation between students’ reading comprehension
ability with their examination results. I did a series of steps in my research and the result of the research is
described as the following:
4.1 Statistical Analysis
