a. Content Validity
This validity concerns with the content details of the instruments. This validity analysis analyzes all the content of the instruments or tests whether the content of
the instruments represents the material that would be measured by the instruments. The content of the test was presented by the table below:
Table 2. Table of specification
No Objectives
Item Numbers Total Items
Percentage
1 Identify the main idea
1, 8, 16, 20, 28 5
17 2
Inference 2, 12, 13, 18, 27, 29, 30
7 23
3 Reference
6, 11, 14, 23 4
13 4
Specific information 3, 4, 9, 10, 17, 21, 24, 25, 26
9 30
5 Vocabulary
5, 7, 15, 19, 22 5
17
Total 30
100
b. Construct Validity
This validity was used to the instruments which have some indicator to measure one aspect. The construct validity of the instruments are measured by evaluating
the content whether all the content of the instrument concern to one aspect or not.
3.6.3 Level of Difficulties
The writer used the following formula to see the level of difficulty of the tests. It was calculated by the following formula:
�� = �
Notes: LD
: level of difficulties R
: the number of the students who answer correctly N
: the total number of the students Shohamy, 1985:79
3.6.4 Discrimination Power
The writer used the following formula to see the discrimination power:
�� = −
Shohamy, 1985:81 The criteria were:
1. If the value is positive, it has discrimination because a large number or more
knowledgeable students than poor students got the item correct. If the value was zero, it means no discrimination.
2. If the value is negative, it has negative discrimination because more low-level
students than high-level students got the item correct. 3.
In general, the higher discrimination index, the better, in the classroom situation most items should be higher than 0.20indexes.
Shohamy, 1985:82
3.7 Data Analysis
In this research, there are two variables: independent and dependent variable. To collect the data of this research, the writer used test for two variables, they are
self-esteem test and reading comprehension test. Self-esteem is the independent variable because the writer assumes that self-esteem influences the
students’ reading achievement.
The students’ reading achievement is classified as the dependent variable which is affected by the self-esteem. Having collected the data
of two variables, the writer analyzed the data by using One-Way Anova with the significant value 0.05 that was computed by using SPSS.
3.8 Hypothesis Testing
The writer determined the criterion of the hypothesis acceptance. To decide whether the first hypothesis were accepted or rejected, the following criterion
acceptance were used:
H = F
value
F
table
H
1
= F
value
F
table
Notes: H
o
: there is no significant effect ofstudents’ self-esteem on their
reading comprehension achievement H
1
: there is a significant effect of students’ self-esteem and their
reading comprehension achievement
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