6. Determining Standard Error of Mean of Variable Y, the formula is: SE
M
2
= SD
2
N
2
− 1 =
2.33 25 − 1
= 2.33
24 =
2.33 4.89
= .
7. Determining Standard Error of Difference of Mean of Variable X and Variable y, with formula:
SE
M
1
−M
2
= SE
M
1
2
+ SE
M
2
2
SE
M
1
−M
2
= 0.73
2
+ 0.47
2
SE
M
1
−M
2
= 0.5329 + 0.2916
SE
M
1
−M
2
= 0.8245
��
� −�
= .
8. Determining t with formula:
t =
M
1
−M
2
SE
M1 −M2
t =
17.92 − 11.68
0.908 t
= 6.24
0.908 � = .
9. Determining degree of freedom df, with formula: df =
N
1
+ N
2
− 2 df =
25 + 25 − 2 df = 50
− 2 �� =
df = 48 see the table of “t” values at the significance level of 5 = 2.011.
The value of df 48 at the degrees of significance 5 or t
table
is 2.011
3. The Data Interpretation
According to the calculation of the data, for the experiment class, the mean of the pre-test is 54, the mean of the post-test is 73.93, and the mean of the
gained score is 19.93; while for the control class, the mean of the pre-test is 52.4, the mean of the post-test is 71.13, and the mean of the gained score is
18.73. It means that the mean of the pre-test, the post-test, and the gained score in the experiment class are higher than the mean of the pre-test, the post-
test, and the gained score in the control class. Furthermore, the calculation of t-observation is 6.87 and the value of df
48 at significance level of 5 is 2.011. Comparing the t-observation with the t-table, the result of this study shows that t-observation t
o
= 6.87 is higher than t-table t
t
5 = 2.011 or 6.87 2.011. Because t-observation is higher than t-table t
o
t
t
in 5 significance level, so that the alternative hypothesis Ha is accepted and the null hypothesis Ho is rejected.
Based on Larsen-Freeman ’s argument in Chapter I, it has been proved that
the particular technique and strategy might look very different and might lead students to very different conclusions about their learning depending on how
the teachers managed. The writer feels that using visual media especially picture in teaching grammar give him lot of benefit; according to Celce-
Murcia and Hilles in Chapter I, the picture can be used in all phases of a grammar lesson i.e., in presentation, focused practice, communicative
practice, and for feedback and correction. Interesting ad entertaining pictures also motivate student to give a feedback of teacher’s explanation.
Especially for teaching degree of comparison, Ur in Chapter II highlighted that picture can be used for structured practiced and communicative practiced.
For structured practiced, the teacher gives each pair of students a picture of George and Bill who have different age; and both of students have to compare
their age by using comparative degree. While for communicative practice, students have to sit back to back so they cannot see each others pictures. Thus
the two students have to ask each other many questions and share a lot of information. In this activity, the students have a conversation to share a lot of
information about their pictures; they can think and talk about their picture by themselves naturally. Last but not least, in any non English lesson, the picture
also give lot of advantages, it can be used to play games, to illustrate stories, and to do numerous other activities such as to assist teacher in presentation or
to exercise based on Finocchiaro argument’s in chapter II. In conclusion, it can be interpreted that there is significant difference
between students’ achievement who were taught degrees of comparison by using pictures and those who were taught degree of comparison without using
pictures. So, that teaching the degree of comparison by using pictures is effective and applicable.
4. The Test of Hypothesis
After calculating the data, the writer tested his hypothesis based on the statistical hypothesis. The statistical hypothesis states:
a. If t-test t t-table t
t
: there is significant difference of students’
achievement that are taught degree of comparison through picture and without picture. the alternative Hypothesis Ha is accepted and null
Hypothesis H is rejected
b. If t-test t t-table t
t
: there is no significant difference of students’
achievement who are taught degree of comparison through picture and without picture. the alternative Hypothesis Ha is accepted and null
Hypothesis H is rejected.
