Talk:F-test

message: Yeah, working through an example is great, but I'm not sure why all the calculations are needed. In particular calculating the column means (\overline{Y}) leads me into being very confused about calculating [Y] since they were the only previous Y's. Clearly I wasn't paying enough attention to the overline, but then I don't see why
they are needed at all; \overline{Y}_T also seems unnecessary. Please correct me if I'm wrong.
I also added a few sentences near the beginning in response to the many requests for simpler explanation. I hope they help a bit, and more importantly, are accurate. Regrettably, they also rely on the "factor-group" assumption, which Melcombe has already criticized (below in "Improvement required"). Does this need to be generalized, or is the categorical assumption correct for anovas? Obviously, my own understanding is still not strong enough here.
Also, perhaps these lines are too redundant with other attempts at simple clarity further below. Probably be nice to combine and get into the best spot, but trying to keep my modifications minimal given my own amateurness.
—Preceding unsigned comment added by Potamites (talk • contribs) 19:01, 25 April 2009 (UTC)
thread_title:  helpful example but all necessary?? 

message: I think it would be nice, if one can proved the standard form of reporting the F score: F(within group, between group)= ...
:Not clear Dfarrar 12:53, 18 April 2007 (UTC)
thread_title:  [A suggestion] 

message: Needs simpler explanation including examples of use.GraemeLeggett 08:13, 7 September 2007 (UTC)
thread_title:  This article is almost completely inpenetrable to the average reader 

message: I think the RSS in the Numerator should be RSS_2, not RSS_1, see e.g.: http://www.graphpad.com/help/Prism5/prism5help.html?howtheftestworks.htm -- user withouth account (sorry)
Insert formula here
I also think it is wrong. I am getting negative F values.  — Preceding unsigned comment added by 165.123.243.100 (talk) 17:22, 11 October 2013 (UTC)
thread_title:  [Error in Formula?] 

message: I am unhappy about the statement 
:"The general formula for an F- test is: F = (between-group variability) / (within-group variability)"
... since F-tests are used when there are no obvious "groups". Melcombe (talk) 09:24, 10 April 2008 (UTC)
thread_title: Improvement required

message: Can someone put out a call for help to the stat email lists or the statistics teaching email lists?  Surely this does not have to be painful.
WikiStat (talk) 18:56, 14 April 2008 (UTC)
thread_title: Call for Help

message: I had the chance to look up the general formuela again I'd stand by it for two reasons:1) SPSS output uses this notation for one way ANOVA 2) I looked this up in my stats book from college and it is was as I remembered it.
143.109.134.157 (talk) 04:23, 22 April 2008 (UTC)
thread_title: General Formula

message: The F-test for equality of variances is now characterized as being "extremely sensitive to non-normality". I'm generally opposed to such characterizations as it is hard for a casual reader to judge what "extreme" means.  It could easily be misinterpreted as meaning something stronger than is actually warranted.  But I don't have any direct experience with this rather obscure F-test (which is not the much more familiar ANOVA F-test). Skbkekas (talk) 04:55, 16 December 2010 (UTC)
thread_title:  Sensitivity to non-normality 

message: I think the 1-rss2 in the denominator of the test statistic doesn't make sense becuase it can produce negative values.  I think it should be simply rss2.  — Preceding unsigned comment added by 68.149.167.250 (talk) 16:05, 2 September 2011 (UTC)
replies: text: Agreed. The "1-" was added on 31 August by an IP editor. I've just undone that edit. Qwfp (talk) 07:48, 3 September 2011 (UTC)
thread_title:  Error in Nested F-test section? 

message: At the end of the section on one-way anova in the "post-hoc" analysis, it is not clear where the standard error formula comes from; should it not be something like: \sqrt{\frac{\frac{(1-3\frac13)^2 + (4-3\frac13)^2 + (5-3\frac13)^2}{2}}{3}}=1.2 (where 3\frac13 is the mean)?  — Preceding unsigned comment added by 93.172.96.24 (talk) 15:33, 21 September 2011 (UTC)
thread_title:  One-way ANOVA example standard error 

message: Does any one think that the One-way ANOVA example should be copied to the One-way ANOVA page? --IcyEd (talk) 12:07, 3 June 2013 (UTC)
thread_title:  One-way ANOVA example - copy to One-way ANOVA page? 

message: Seems kind of important but appears to be missing from the page...  — Preceding unsigned comment added by 74.72.229.113 (talk) 03:04, 17 January 2014 (UTC)
thread_title:  Missing testing null hypothesis that all betas are equal to zero 

message: The Formula for the F-test in the regression section was incoherent with the degrees of freedom used for the F-test after the formula.
Could someone with a statistics backgroud check the validity of the fomula in its current state?
79.60.157.114 (talk) 03:47, 7 March 2018 (UTC)
thread_title:  Possible error in the F-test formula for the regression