+ Reply to Thread
Results 1 to 1 of 1

Thread: F Stat vs. T Stat relationship

  1. #1
    Points: 3,466, Level: 36
    Level completed: 78%, Points required for next Level: 34

    Thanked 0 Times in 0 Posts

    F Stat vs. T Stat relationship

    I have a question about the F Stat vs. T stat relationship. I know that for ANOVA, the F stat = t^2, thus the p value of the (non-directional) F stat can be cut in half for a directional test (which is equivalent to a 1 tailed t test). Is the same true for an ANCOVA? What I am trying to do is test whether 1 group scores higher on a measure than another group, but my design uses covariates (thus the ANCOVA instead of a regular ANOVA). My impression is that since I'm talking about a relationship between the F and t distributions, that using the F stat from the ANCOVA and cutting the corresponding P-value in half would be equivalent to the p value of a one-tailed t test with the same degrees of freedom, and thus allow me to do a directional ANCOVA as I desire. (This uses the relationship of F=t^2 to find t, and the p value of the one tailed t-test with the same degrees of freedom would be ½ the p value of the two tailed t test, or the non-directional F test). I would like to make sure that this is accurate from a statistical standpoint. If not, is there an alternative way to do a directional ANCOVA test?

    Can anyone shed some light on this and/or give me a good reference for some reading on the subject.

    Last edited by confused; 02-20-2008 at 02:30 PM. Reason: innacurate wording in the question

+ Reply to Thread


Similar Threads

  1. More than just stat
    By lilfish08 in forum Statistics
    Replies: 12
    Last Post: 09-15-2010, 01:06 PM
  2. Stat help
    By p1ngputts in forum Statistics
    Replies: 4
    Last Post: 12-03-2008, 01:48 PM
  3. need help with stat problem
    By sunstone in forum Statistics
    Replies: 1
    Last Post: 10-27-2008, 02:47 AM
  4. Stat help please
    By wnachifa in forum Statistics
    Replies: 0
    Last Post: 06-16-2008, 03:58 PM
  5. stat example
    By needhelpforstat in forum Probability
    Replies: 1
    Last Post: 12-10-2006, 08:05 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts

Advertise on Talk Stats