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                            In the hypothesis testing are two kinds of errors, namely the type I error

                     and the type II error. Type I error is a mistake to reject H0 when in fact H0 is
                     true. Type II error is the error accept H0 when in fact H1 is true.

                            Probability of a type I error occurs is denoted by  (alpha), which is often

                     also  called  the  significance  level.  While  probability  of  type  II  error  occurs

                     denoted by  (beta). In statistical hypothesis testing, probability of the two types

                     of  errors  are  expected  balanced  and  tailored  to  the  problem  under  study.
                     Probability value 1 -  is called the confidence interval, expressed probability

                     accept H0 when it is true.  Probability value 1 -  is called the power of the test,

                     states the probability to reject H0 when H0 is false.



                     4.1   HYPOTHESIS TESTING FOR SINGLE
                           POPULATION MEAN


                            The data of a sample taken from a population can be used to assess the

                     characteristics of its population. One of  the most interesting characteristics of

                     the  population to  be  studied  is  the  mean value.  There  are  three  forms  of the

                     formulation  of  a  test  hypothesis  for  the  mean  value  of  single  population,

                     namely:
                     1      H0  :   =  o
                            H   :     o
                              1

                     2      H0  :     o
                            H  :   <  o                                                         ( H1 )
                              1

                     3      H0  :     o
                            H  :   >  o
                              1

                            In the conduct of any hypothesis test, there are five steps to be followed :
                        a.  Formulating a test hypothesis, namely the null hypothesis (H0) and the

                            alternative hypothesis (H1). It is one of the formulas above.

                        b.  Calculate the sample statistics, ie the mean value of the sample  X







                                           ~~* CHAPTER 4   HYPOTHESIS TESTING *~~
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