Two tailed F test, correct rejection of the null hypothesis












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I am performing an F test for equality of two variances by following this website formula https://itl.nist.gov/div898/handbook/eda/section3/eda359.htm, however it states that




In the above formulas for the critical regions, the Handbook follows the convention that Fα is the upper critical value from the F distribution and F1-α is the lower critical value from the F distribution. Note that this is the opposite of the designation used by some texts and software programs.




What are currently considered the right upper and lower critical values?
In two textbooks I actually found the designation opposite to the one given by the website. However,




given two samples m,n of 5 and 4 respectively,
a = 0.05,
the critical values are:
F1-a/2(m-1,n-1) = F0.975(4,3) = 0.10
Fa/2(m-1,n-1) = F0.025(4,3) = 9.97


To my understanding, F0.025 is the left tail limit and F0.975 the right tail limit. If this is correct, why has the left tail limit a higher critical value than the other?










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    0












    $begingroup$


    I am performing an F test for equality of two variances by following this website formula https://itl.nist.gov/div898/handbook/eda/section3/eda359.htm, however it states that




    In the above formulas for the critical regions, the Handbook follows the convention that Fα is the upper critical value from the F distribution and F1-α is the lower critical value from the F distribution. Note that this is the opposite of the designation used by some texts and software programs.




    What are currently considered the right upper and lower critical values?
    In two textbooks I actually found the designation opposite to the one given by the website. However,




    given two samples m,n of 5 and 4 respectively,
    a = 0.05,
    the critical values are:
    F1-a/2(m-1,n-1) = F0.975(4,3) = 0.10
    Fa/2(m-1,n-1) = F0.025(4,3) = 9.97


    To my understanding, F0.025 is the left tail limit and F0.975 the right tail limit. If this is correct, why has the left tail limit a higher critical value than the other?










    share|improve this question











    $endgroup$















      0












      0








      0





      $begingroup$


      I am performing an F test for equality of two variances by following this website formula https://itl.nist.gov/div898/handbook/eda/section3/eda359.htm, however it states that




      In the above formulas for the critical regions, the Handbook follows the convention that Fα is the upper critical value from the F distribution and F1-α is the lower critical value from the F distribution. Note that this is the opposite of the designation used by some texts and software programs.




      What are currently considered the right upper and lower critical values?
      In two textbooks I actually found the designation opposite to the one given by the website. However,




      given two samples m,n of 5 and 4 respectively,
      a = 0.05,
      the critical values are:
      F1-a/2(m-1,n-1) = F0.975(4,3) = 0.10
      Fa/2(m-1,n-1) = F0.025(4,3) = 9.97


      To my understanding, F0.025 is the left tail limit and F0.975 the right tail limit. If this is correct, why has the left tail limit a higher critical value than the other?










      share|improve this question











      $endgroup$




      I am performing an F test for equality of two variances by following this website formula https://itl.nist.gov/div898/handbook/eda/section3/eda359.htm, however it states that




      In the above formulas for the critical regions, the Handbook follows the convention that Fα is the upper critical value from the F distribution and F1-α is the lower critical value from the F distribution. Note that this is the opposite of the designation used by some texts and software programs.




      What are currently considered the right upper and lower critical values?
      In two textbooks I actually found the designation opposite to the one given by the website. However,




      given two samples m,n of 5 and 4 respectively,
      a = 0.05,
      the critical values are:
      F1-a/2(m-1,n-1) = F0.975(4,3) = 0.10
      Fa/2(m-1,n-1) = F0.025(4,3) = 9.97


      To my understanding, F0.025 is the left tail limit and F0.975 the right tail limit. If this is correct, why has the left tail limit a higher critical value than the other?







      statistics variance






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      edited 1 min ago







      Camilla

















      asked 10 mins ago









      CamillaCamilla

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