Research Finding

A. Research Finding

1. Description of the Data

The data of this research was the score of students’ post test. The researcher had given post test to both samples where the students were asked to create writing recount text about their holiday.

Actually, there are 59 students who are involved in the post test. Those students were divided into two classes, 29 students for experimental class and 30 students for control class. The researcher taught writing recount text by using Pow Tree strategy in experimental Actually, there are 59 students who are involved in the post test. Those students were divided into two classes, 29 students for experimental class and 30 students for control class. The researcher taught writing recount text by using Pow Tree strategy in experimental

All of the data were analyzed to find out the maximum and minimum scores, mean scores and standard deviation of post test of experimental and control class. The post-test data of experimental and control classes were shown as follows;

Table 4.1 The Score of Writing Test of Experimental Group and Control Group

Total Standard Class

score Deviation Experimental 29

The total score of writing test of both groups was significantly different. The total score of experimental group was 2393, the highest score was 90, the lowest score was 73, and standard deviation was 3.4. On the contrary, the total score of control group was 2258, the highest score was 82, the lowest score was 65 and standard deviation was 15.995.

2. Data Analysis

a. Experiment Class

X max : 90

n : 29

X max -X min

K : 1+3,3 log n Note :

X min : 73

I : R/K

I = Interval R = Range K = Number of Classes

R:X max -X min

= 90-73= 17 K : 1+3,3 log n

= 1+3,3 log 29 = 1+3,3 1,46 = 1+4,76= 5,76 = 6

=17/5,76=2,95 The interval of students writing score was 6. then the interval data of experimental class post test score can be seen in the table below.

I : R/K

Table 4.2 The Interval Data of Experimental Class Post Test Score VIII 3 Interval

No (Students’ Writing Scores) Frequency

1 73-75

2 76-78

3 79-81

4 82-84

5 85-87

6 88-90

Total

From the table above, it was found that most of students’ writing post test score in the experimental class was about 73-75,

there was 1 student got score at that interval, while the interval 76-78 there were 2 students, at interval 79-81 there were 7 students who got score at that interval, in the interval 82-84 there were 11

students, at interval 85-87 there were 6 students, and in the interval 88-90 there were 2 students who got score in that interval. The interval can be drawn as follow.

6 4 73-75 76-78 79-81 82-

84 85-87 88-90 2

73-75 76-78 79-81 82-84 85-87 88-90

Table 4.3

Calculation Process of Mean and Standard Deviation of Writing Test

2 Xi 2 Fi Xi Fi.Xi Fi.Xi

Experimental Group

F 1 X 1 2393

1 X 1 ) =  2393  = 5726449

S 1 = 3.4 Based on the table formulation above, researcher found that

mean of writing test experimental class was 82.52 and standard deviation was 3.4.

b. Control Class

K : 1+3,3 log n Note :

X min : 65

I : R/K

I = Interval R = Range K = Number of Classes

R:X max -X min

= 82-65= 17 K : 1+3,3 log n

= 1+3,3 log 30 = 1+3,3 1,47 = 1+4,77= 5,77 = 6

=17/5,77=2,94 The interval of students writing score was 6. then the interval data of experimental class post test score can be seen in the table below.

I : R/K

Table 4.4

The Interval Data of Control Class Post Test Score VIII 5

Interval

No (Students’ Writing Scores) Frequency

1 65-67

2 68-70

3 71-73

4 74-76

5 77-79

From the table above, it was found that most of students’ writing scores of post test in the control class about 65-67, where there was 1 student got

score at that interval, at interval 68-70 there were 4 students who got score at that interval, at interval 71-73 there were 3 students who got score at that interval. at interval 74-76 there were 10 students who got score at that interval, at interval 77-79 there were 8 students who got score at that interval and the last interval 80-82 there were 4 students who got score at that interval. The interval can be drawn as follow.

6 65-67 68-70 71-73 74-

4 76 77-79 80-82

65-67 68-70 71-73 74-76 77-79 80-82

Table 4.5

2 Xi 2 Fi Xi Fi Xi Fi Xi

Process of

Mean and

Standard Deviation of

Writing Test

F 2 X 2 2258

2 X 2 ) =  2258  = 5098564

2 = 15.995 S 2 = 15 . 995 S 2 = 3.99

Based on the table formulation above, researcher found that mean of writing test experimental class was 75.27 and standard deviation was 3.99. To explain more about Pow Tree strategy gives significant effect on students’ Based on the table formulation above, researcher found that mean of writing test experimental class was 75.27 and standard deviation was 3.99. To explain more about Pow Tree strategy gives significant effect on students’

Table 4.6 The Calculation of Comparison of Means Post-test of Experimental and

Control Class in Content, Organization, Vocabulary, Language Use, and Mechanic

No Aspects/

Difference Components

Post-test (Exp)

Post-test (Con)

4 Language Use

From the table of calculation of comparison of means post-test and control class can be explained that:

1. Content In experimental class, the mean post test scores of the students’ content was 24.58 while in control class, the mean of post test was 20.06 with 1. Content In experimental class, the mean post test scores of the students’ content was 24.58 while in control class, the mean of post test was 20.06 with

2. Organization In experimental class, the mean post test score of the students’ organization was 17.48 while in control class, the mean scores of post test was 16.6 with difference 0.88. It can be said that Pow Tree strategy helped the students in developing their ideas clearly in writing. Besides it made they have good competence in describe of an organization such as fluent expression, ideas clearly stated/supported, succinct, well-organized, and logical sequencing, and cohesive.

3. Vocabulary In experimental class, th e mean post test score of the students’ vocabulary was 17.93 while in control class, the mean scores of post test was

17.5 with difference 0.43. It can be said that Pow Tree strategy helped the students highly in mastering vocabulary. In addition based on the students’ writing, it showed that students had been developed their knowledge in descriptor of a vocabulary such as sophisticated range, effective word or idiom choice and usage, word form mastery, and appropriate register.

4. Language use In experiment al class, the mean post test score of the students’ language use was 19.89 while in control class, the mean scores of post test was 18.46 with difference 1.43. It can be said that Pow Tree strategy helped the students in mastering the language use.

5. Mechanics In experimental class, the mean post test score of the students’ mechanic was 2.62 while in control class, the mean scores of post test was 2.3 with difference 0.32. It can be said that the students’ writing who were in experiment class was better in every aspect. It showed that students had sufficient capability in using appropriate mechanics such as in punctuation, spelling, capitalization and paragraphing.

Meanwhile, to see what component of students’ writing were mostly significant, it can be seen from the different all component writing of both class.

First content, the different of both classes in content was 4.52. Second organization, the different of both classes in organization was 0.88. Third vocabulary, the different of both classes in vocabulary was 0.43 . Fourth language use, the different of both classes in language use was 1.43. The last mechanic, the different of both classes in mechanic was 0.32. So, from the explanation above, the researcher can said that the component of students’ writing were mostly have significant effect is content with different 4.52 from the both classes.

Based on the explanation above showed the students’ writing competence in aspects of content, organization, vocabulary, language use and

mechanic has really developed and the use of Pow Tree strategy for experimental have higher performance than Conventional strategy. It means that the hypothesis of this research was accepted.

3. Inferential Data Analysis

1) Prerequisite Hypothesis Testing

The prerequisite is necessary to determine whether the analysis of data for hypothesis testing can be continued or not. Some data analysis techniques demanding test prerequisite analysis. Analysis of variance requisite that data come from a population with normal distribution and group compared to homogeneous of data.

a. The normality of distribution test

Normality test had an objective to know the population normal or not. In this research, to do the normality test the researcher used Kolmogrov Smirnov and Shapiro Wilk. Test was performed in SPSS test. Testing criterion and distributed normal if the data was more than 0.05. The class was normal. Base on that test, the researcher got test of normality

class VIII 3 as experiment class. The summary of the result of test of normality and homogeneity of experiment group and control group is presented in the table below:

Table 4.7 The Result of Testing Normality Writing Post-Test

Tests of Normality

Kolmogorov-Smirnov a Shapiro-Wilk

VAR00 002

df Sig. VAR00001

Statistic

df Sig.

30 .132 a. Lilliefors Significance Correction

*. This is a lower bound of the true significance.

b. The homogeneity of variance test

To check the homogeneity of variance of the data, Levene’s test was conducted. The result of calculate using Levene test is as follows:

Table 4.8 The Result of Testing Homogeneity Writing Post-Test

Test of Homogeneity of Variance

df2 Sig. VAR00001

Levene Statistic

df1

Based on Mean

1 57 .411 Based on Median

.685

1 57 .463 Based on Median and with

.545

adjusted df

1 55.719 .463 Based on trimmed mean

Based on the table above, it can be said that two groups was normality and homogeneous. After the test of normality and homogeneity, the data were analyzed by using t- test by (Sudjana, 2005: 239) to see the effect of using Pow Tree strategies, the data observed of this research was analyzed by using t-test.

c. Hypothesis Testing

In order to see the effect of Pow Tree strategy gave any significant effect on students’ writing ability in these classes,

the data that was observed of this research was analyzed by using T test.

The calculation of T test between mean score of experiment and control group could be figured bellow:

= (29-1) 11.56 + (30-1) 15.92

29 + 30 - 2 = (28) 11.56 + (29) 15.92

57 S 2 = 13.78

S= 13 . 78

S = 3.71

s 1 1 n 1 n 2

0.93 t  7 . 795

df   n 1  n 2  2 

t- table =t (1- α ) (df)

=t (1-0.05) (57)

=t( 0.95) (57)

t- Table = 2.000

t- Calculate > t- table

From data analysis, it is found that t-calculated is 7.795, while critical value of the t- table is 2.000 at the degree of freedom were 54 and the level of significant is 0.05. The value of t- calculated in this research was higher than the value of t- table . It means that there is significant effect on students’ achievement between students’ are taught by Pow Tree strategy

than Conventional strategy at VIII Grade of Junior High School 1 Painan