Page 66 - Basic Statistics

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(use the value of the first sample variance S1 )
2
σ ˆ 2 = Estimated value for the second population variance
2
(use the value of the second sample variance S2 )
2
n1 = Number of observations in the first sample

n2 = Number of observations in the second sample

Testing criteria :

If this test using significance level  and Z obtained from (N2) or (N4),

then criteria to test the equality of the average of two independent populations

(two-tailed test):

H0 is accepted if  Z-actual   Z/2-table , or

Pr = [ P ( Z  -z actual ) + P ( Z  z actual) ]   , otherwise

H0 is rejected if  Z-actual  > Z/2-table , or

Pr = [ P ( Z  -z actual ) + P ( Z  z actual) ] < .

To test whether the means of the first population is smaller than the mean

of second population, one-tailed test was used, with the following formulation of

the test hypothesis

H0 : μ = μ
1
2
( N6 )
H1 : μ < μ
2
1

Testing the hypothesis (N6) with a normal distribution approach, using the
same formula with the value of Z in testing hypotheses (N1), namely:

a. If both population variance ( 1 and 2 ) is known, then
2
2
X X −
Z-hitung = 1 2 ( N2 )
σ
X 1 − X 2

~~* CHAPTER 4 TESTING HYPOTHESIS *~~