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                         CHAPTER III 
                      RESERCH METHODOLOGY 
           3.1 Research Method 
             This research use quasi experimental design. Quasi experimental research is a 
           good  design  of  the  research  because  although  it  is  not  true  experiments,  it 
           provides reasonable controlled over most sources of invalidity and it is usually 
           stronger  than  the  pre  experimental  design  (McMillan  and  Schumacher,  2006). 
           Quasi  experimental  is  a  design  where  the  researcher  is  able  to  control  the 
           treatment but is not able to randomly assign the subject of the treatment (Ary, 
           2010). 
             Quasi experimental design focuses on treatment and outcome, hence the data 
           take  from pre test and post test in order to know whether mind mapping can 
           improve english writing skill of descriptive text. In this research design, there are 
           two kinds of classes used. There are the experimental class were given treatment 
           by  using  mind  mapping  and  controlled  class  by  without  mind  mapping  (Ary, 
           2010). 
           3.2 Hypotheses 
             This research has two hypotheses. The two hypotheses are null hypothesis 
           (H0) and alternative hypothesis (H1) that described as follows: 
           1) The null hypothesis (H0)
            Mind mapping can not improve English writing skill of descriptive text at the
            eight grade of SMPN 6 Pasuruan.
           2) The alternative hypothesis (H1)
            Mind mapping can improve English writing skill of descriptive text at the eight
            grade of SMPN 6 Pasuruan
           1.3  Population And Sample 
             Population  in  this  research  are  second  grade  students  of  SMPN  6  Kota 
           Pasuruan. Population is the group of interest to researcher, the group to whom the 
           researcher  would  like  to  generalize  the  result  of  study  (Sanjaya,  2013).  The 
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           population  of  this  research  is  the  second  grade  students  of  SMPN  6  Kota 
           Pasuruan. There are eight classes there (VIII-A, VIII-B, VIII-C, VIII-D, VIII-E, 
           VIII-F, VIII-G, VIII-H). The quantity of the students in second grade are 250 
           students.   
             Sample is portion of population (Azwar, 2010). the sample of this research 
           taken by two class from eight class that have the lower score of the middle test in 
           eight grade. The lower score of the middle test got by VIII-G (53) and VIII-H 
           (42). In addition, VIII-H become experimental  class and VIII-G become control 
           class and VIII-G has 30 students and than VIII-H has 30 students. A tecnique of 
           sampling is purposive sampling. Purposive sampling is choosing the sampling 
           based on the certain puposes to support the research (Sukardi, 2003). 
              
           3.4 Data Collection 
             This research used student’s score of pre test and post test as the data. To 
           collect  the  data,  the  research  needed  an  instrument  and  needed  to  do  several 
           procedures.  
              
           3.5 Instruments And Data Gathering Technique 
             Instruments is a tools that is use to collect and analyze the data objectively 
           and systematic in order to solve a problem or testing a hypothesis (Sanjaya, 2013). 
           In this study the researcher use pre test and post test instrument. The test related to 
           descriptive text. 
             Data gathering technique is a systematic procedures and standards to obtain 
           the  necessary  data  (Nasir,  2003).  Data  gathering  technique  in  this  study  use 
           student’s writing score of pre test and post test. The resercher need an instrument 
           and need to do several procedures. 
              
           3.6 Data Analysis Technique 
             The gathered data use to find out the differences of students’achievement in 
           experimental  class  and  controlled  class.  In  line  with  this,  the  resercher  uses 
           independent  sampel  t-test.  It  is  use  to  examine  the  significance  difference  of 
           student’s writing skill of descriptive text achievement between experimental class 
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                            and controlled class. The researcher use SPSS 21 versions to ease calculation the 
                            data. The formula of t-test as follow (Sudijono, 2006): 
                                                                         
                            Notes: 
                            M1 = Mean of Variable X (experimental class) 
                            M2 = Mean of variable Y (controlled class) 
                            SEM1 = Standard Error Mean of Variable X (experimental class) 
                            SE = Standard Error Mean of variable Y (controlled class) 
                               M2                       
                             
                                 To prove hypothesis, the data obtained in experimental class and control class 
                            are calculated by using p-value.  p-value is error value obtained from statistical 
                            calculations with assumption as follows (Riduwan et al., 2011): 
                             1)  If p-value > error of degree (α) 0.05 the null hypothesis (H0) is accepted and 
                                 alternative hypothesis (H1) is rejected. It is proven that Mind mapping can 
                                 not improve English writing skill of descriptive text at the eight grade of 
                                 SMPN 6 Pasuruan. 
                             2)  If p-value < error of degree (α) 0.05 the null hypothesis (H0) is rejected and 
                                 alternative hypothesis (H1) is accepted. It is proven that Mind mapping can 
                                 improve English writing skill of descriptive text at the eight grade of SMPN 6 
                                 Pasuruan. 
                             
                            3.7  RESEARCH PROCEDURE  
                                 The data for this study is obtain from the student scores of writing pre test 
                            and post test. To collect the data the procedure of research as follow:  
                            1.   Giving pre test 
                                 Pre test is delivere at the first time before the researcher apply the treatment 
                                 in experimental and control class.  
                            2.   Giving treatment 
                                 After  pre  test,  the  researcher  give  treatment  to  experimental  class. 
                                 Experimental  class  were  given  treatment  by  using  mind  mapping  and 
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                                 controlled class by without mind mapping. The treatment for experimental 
                                 class were given only two meeting. 
                            3.   Giving post test 
                                 After the treatment, the researcher give a post test to experimental and control 
                                 class.  By  giving  the  post  test,  the  researcher  know  whether  the 
                                 implementation of mind mapping in writing descriptive text has a significant 
                                 role in increas students writing english skill or not.  After that, the pre-test 
                                 and post test that produced will be scored by the researchers and classroom 
                                 teachers. It’s done in order to the value is given can be valid.