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Homework Help: Basic F-statistic question

  1. Nov 6, 2005 #1
    Consider the test of the hypotheses:
    Null: (sigma1)^2>=(sigma2)^2
    Alternative: (sigma1)^2<(sigma2)^2
    where α = 0.05 and:
    n1 = 8 and s1 = 13.0
    n2 = 10 and s2 = 11.5.
    What is the test statistic for F?

    Your Answer:
    1.278
    Correct Answer:
    1.278

    If the alternative hypothesis for two variances has "<", couldn't you switch the s1 and s2 in the f-stat equation to create an upper-tail test? if so, my test statistic would be 0.783
     
  2. jcsd
  3. Sep 7, 2007 #2

    EnumaElish

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    Science Advisor
    Homework Helper

    F test is a one-sided test. The square root of the F statistic is the absolute value of the t statistic for the one-sided test.
     
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