correlation analysis. The correlation coefficient was then interpreted to find out the relationship between students’ vocabulary mastery and their translation ability.
3.2 Population
In quantitative research, the researchers attempt to discover something about a large group of individuals by studying a much smaller group. According to
Lodico 2006:140, “A population is the wider group of individuals about which the researcher wants to make statements”.
“The population is the group of people we want to generalize to.” Muijs, 2004:15. The population is the group that the researcher wants to generalize
hisher findings to. Based on the definition above, the population of this study was the second
year students of SMA Negeri 1 Blora in the academic year of 20102011. The total number of the second year students of SMA Negeri 1 Blora is 297. They are
XI IA 1= 31, XI IA 2= 30, XI IA 3= 30, XI IA 4= 30, XI IA 5= 30, XI IS 1= 38, XI IS 2= 36, XI IS 3= 38, XI IS 4= 34.
3.3 Sample
Lodico in his book Methods in Educational Research stated, “A sample is a smaller group selected from a larger population in this case, a realistic
population that is representative of the larger population. Samples allow researchers to work with a smaller, more manageable subgroup of the realistic
population. Lodico, 2006:143.
There are some sampling techniques in quantitative research. For example, simple random sampling it involves the random selection of individuals from the
realistic population as a whole, stratified random sampling it would allow the researcher to stratify along the variable of party affiliation—that is, to select a
sample that was more representative of the population, cluster random sampling numbers are assigned to the cluster or subgroup within the realistic, and
convenience sampling. In this research, I used random sampling technique to choose the samples.
The total number of the eleventh grade of SMA Negeri 1 Blora is 297. According to Arikunto 2002:112, in random sampling technique, if the subject is more than
100, sample can be taken between 10-15 or 20-25 or more. Therefore, in this research, I took 30 students as the sample or approximately 10 of the
population.
3.4 Variable
According to Muijs 2004:8, variables are any characteristic of the unit we are interested in and want to collect e.g. gender, age, self-esteem. On the other
hand, Brown 2005:7 stated that a variable is something that may vary, or differ. Moreover, Brown 2005:8 also stated that the operationalization of variables
is a researcher’s chance to explain how each variable is being defined with respect to the construct in question.
From the definition above, it can be concluded that research variable includes the factors or the conditions that have a role in the phenomena. In order to assess
the relationship between variables in a study, the variable should be identified. In this study, there are two variables; they are dependent variable and independent
variable.
3.4.1 Independent Variable
An independent variable is variable selected and systematically manipulated by the researcher to determine whether, or the degree to which, it has
any effect on the dependent variable Brown, 2005:11. Tuckman 1978:58-59 stated that the independent variable is that factor which is measured, manipulated,
or selected by the experimenter to determine its relationship to an observed phenomenon.
The independent variable of this study is the students’ vocabulary mastery which is indicated by the vocabulary test.
3.4.2 Dependent Variable
A dependent variable is observed to determine what effect, if any, the other types of variable may have on it. In other words, it is the variable of
focus—the central variable—on which other variables will act if there is any relationship Brown, 2005:10. According to Tuckman 1978:59, the dependent
variable is that factor that appears, disappears, or varies as the experimenter introduces, removes, or varies the independent variable.
Based on the definition above, the dependent variable of this study is the students’ translation ability which is indicated by the score of the translation test.
3.5 Hypotheses
The hypotheses formulated in two laps, they are:
3.5.1 Null Hypothesis H
H0 There is no significant positive relationship between students’ mastery of vocabulary and their translation ability of the second year
students of SMA Negeri 1 Blora.
3.5.2 Alternative Hypothesis H
1
H1 There is a significant positive relationship between students’ mastery of vocabulary and their translation ability of the second year of SMA
Negeri 1 Blora.
Both of the hypotheses will be used in this research. After finding out the result from hypotheses based on the research, it will show which is more
appropriate to draw hypotheses of the research, using null hypothesis or alternative hypothesis.
3.6 Instrument
Instrument is the important thing in an experiment in which the reliability of the instrument will automatically affect the reliability of the data obtained.
Instrument is a means of collecting data. It can be in the form of observational sheet, questionnaire, interview, and test.
In line with the purpose of the study, that is to find out the correlation between students’ mastery of vocabulary and their translation ability of the second
year students of senior high school, the writer used two instruments. The instruments were vocabulary test and translation test.
For the vocabulary test, I used the multiple-choice type in order to facilitate the students to answer the test. The vocabulary test will cover the recognition of
synonyms and antonyms, definitions, and the appropriate word for the context. While in the translation test, the students were asked to translate an English text
into Indonesian.
3.6.1 The Condition of the Test
3.6.1.1 Reliability of the Instrument
Reliability refers to the consistency of scores, that is, an instrument’s
ability to produce “approximately” the same score for an individual over repeated testing or across different raters Lodico, 2006:87. According to Cohen,
Reliability is essentially a synonym for consistency and replicability over time, over instruments and over groups of respondents Cohen, 2000:117.
The instrument said to be reliable when approximately the same result are obtained on different occasion.
Unreliability is clearly a problem. If we measure something unreliably, our results are untrustworthy and any conclusions tainted. Unreliable instruments
will also lead to relationships with other variables being lower than if they were more reliable, thus perverting our ability to come to clear research findings.
3.6.1.2 Validity of the Instrument
Validity is the most important criteria in measuring an instrument. Validity is the touchstone of all types of educational research Cohen, 2000:106.
A test said to be valid when it can measure what is intended to be measured. According to Cohen in his book Research Methods in Education Cohen,
2000:131-132, with regard to validity, it is important to note here that an effective test will ensure adequate: content validity e.g. adequate and
representative coverage of program and test objectives in the test items, a key feature of domain sampling; criterion-related validity where a high correlation
co-efficient exists between the scores on the test and the scores on other accepted tests of the same performance; construct validity e.g. the clear relatedness of a
test item to its proposed constructunobservable quality or trait, demonstrated by both empirical data and logical analysis and debate, i.e. the extent to which
particular constructs or concepts can give an account for performance on the test; concurrent validity where the results of the test concur with results on other tests
or instruments that are testingassessing the same constructperformance—similar to predictive validity but without the time dimension; face validity that,
superficially, the test appears—at face value—to test what it is designed to test; jury validity an important element in construct validity, where it is important to
agree on the conceptions and operationalization of an unobservable construct; predictive validity where results on a test accurately predict subsequent
performance—akin to criterion-related validity; consequential validity where the inferences that can be made from a test are sound; systemic validity where
program activities both enhance test performance and enhance performance of the construct that is being addressed in the objective.
To ensure test validity, then the test must demonstrate fitness for purpose as well as address the several types of validity outlined above.
3.7 Procedures of Collecting Data
The procedures of collecting the data of this research involved several steps. The first step was constructing the vocabulary test and translation test.
The second step was trying out the instrument to examine whether or not they needed improvement. Before conducting the try out, I had got the school
headmaster’s and the English teacher’s permission to do the observation. The third one was collecting and analyzing the vocabulary test and translation
test to measure their validity and reliability. The fourth one was conducting the research. I conducted the research for the
vocabulary test and translation test. The last step was obtaining the scores of vocabulary test and translation test
and then computing the data. The procedures of collecting data of this research can also be seen in the
following diagram:
Figure 3.1 The Procedure of Collecting the Data of the Research
3.8 Procedures of Analyzing Data
