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Very good : 22-20
Average : 19-17
Needs work : 16-0
• has introductory paragraph with clear introductory statement
• has body paragraph with good organization • has concluding paragraph
• has coherence and cohesion Exceptional :
25-23 Very good
: 22-20 Average :
19-17 Needs work
: 16-0
GrammarStructure
• demonstrates control of basic grammar e.g., tenses, verb forms, noun forms, preposition,
articles • shows sophistication of sentence structure
with complex and compound sentences Exceptional :
15-14 Very good
: 13-12 Average :
11-10 Needs work
: 9-0
Word ChoiceWord Form
• demonstrates sophisticated choice of vocabulary items
• has correct idiomatic use of vocabulary • has correct word forms
Exceptional : 10
Very good : 9-8
Average : 7-6
Needs work : 5-0
Mechanics
• has good paragraph format • demonstrates good control over use of
capital letters, periods, commas, and semicolons
• demonstrates control over spelling • does not have fragments, comma splices, or
run-on sentences The students’ score of writing test = content score + organization score +
grammar score + word choice score + mechanics score = 25 + 25 + 25 + 15 + 10 = 100.
While the average of the students’ score in both pretest and posttest was counted by using the formula below:
the total of the students’ score The average of the students’ score =
the total of the students
3.8.2. The t-Test
All data collected of this study were analyzed. I compared the students’ score in pretest and posttest. The results of the comparison were used to answer the
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statement of the problem of this study, whether there is significant difference between writing achievement of students who are taught writing narrative texts by
using video clips and those who are taught without using video clips as media. “A t-test is a statistical test that allows you to compare two means to
determine the probability that the difference between the means is a real difference rather than a chance difference” Tuckman 1978: 257. Based on
Arikunto 2006: 311, the t-test formula is:
Where, t = t value
M
x
= the mean score of the experimental group M
y
= the mean score of the control group Σx
2
= the total of the square deviation of the experimental group Σy
2
= the total of the square deviation of the control group N
x
= the number of the students of the experimental group N
y
= the number of the students of the control group “To decide whether the sample means do differ enough, the researcher must
compare his calculated t value with an appropriate critical value. Two factors which are used to find the correct critical value are the degree of freedom df
associated with his calculated t value and the level of significance” Huck, Cormier, and Bounds1974: 51. To find the degree of freedom df, the formula is:
df = the total number of data observations upon which his t test is based - 2
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Huck, Cormier, and Bounds 1974: 52 state that “after locating the critical value in the t table, the researcher compares his calculated t value against it. If the
calculated t value is larger than the critical value, the researcher is then able to say that a significant difference exists between the two sample means. On the other
hand, if the calculated t value is less than the critical value, the researcher will be forced to conclude that the two sample means are not significantly different from
one another.” In addition, based on http:en.wikipedia.orgwikiStudent’s_t-
test
accessed June 14, 2011, in the t-test comparing the means of two independent samples, the following assumption should be met:
1 Each of the two populations being compared should follow a
normal distribution. This can be tested using a normality test. 2
If using student’s original definition of the t-test, the two populations being compared should have the same variance.
3 The data used to carry out the test should be sampled
independently from the two populations being compared.
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CHAPTER IV DATA ANALYSIS
This chapter deals with the analysis of the data that were found from the activities during the research. It consists of the result of the study, the result of
pretest, and posttest. This chapter also presents the comparison between the result of the pretest and the posttest.
4.1 Results of the Study
The data were obtained from the students’ scores achievement of the writing test of narrative texts. They were pretest scores and posttest scores from the
experimental group and the control group. The total scores of writing test consisted of the scores of five elements of good writing: content, organization,
grammar, word choice, and mechanics score. The complete computation of those five elements scores can be read on Appendix 11, 12, 13, 14. The following tables
are the simple tables for the scores of five elements of good writing for the pretest and the posttest:
Table 4.1 The Simple Table for the Scores of Five Elements of Good Writing for the Pretest
Elements of Good Writing The Experimental Group
The Control Group
Content 658 644
Organization 658 637
Grammar 589 591
Word Choice 381
372 Mechanics 223
225
Total 2509 2469
