User talk:LindaGlass25

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An example of degrees of freedom can be found in the statistics of the health sicences, where the degrees of freedom (df) is the number of participants in a sample minus 1. This minus 1 has to occur to equal out the variance so that it is correct with the larger population from where the sample was taken. Thus formula is:
N-1
N = number of participants in sample
The variance has to be equaled out between the sample and the population thus we take 1 person out of the total number of people to produce a larger variance. This would then be an adequate account for error in variance size (See True Variance).

Hello. I have a number of problems with this passage that you added to degrees of freedom (statistics).

  • Your example is really no different from one already given in the article, so at best it's redundant. Perhaps the explanation can be simplified, but it shouldn't just appear twice for no reason.
  • You seem to suggest that "number of participants in a sample minus 1" applies only in the health sciences, rather than more generally.
  • You don't really given the context. The idea of "number of participants in a sample minus 1" makes sense PROVIDED one is considering residuals resulting from subtraction of a sample average from each observation in a sample. But you didn't say that.
  • Often in the health sciences, as in other fields, the number of degrees of freedom is NOT the "number of participants minus 1". In fairly simple regression problems, it's the number of observations minus 2. And it can be any of various other numbers as well.
  • Please note some differences in mathematical typesetting:
n − 1
n - 1
n−1
n-1
n - 1
n-1
n − 1
etc. And similarly with a capital N. I prefer the first one above, and that's somewhat conventional on Wikipedia. I also prefer lower-case n for sample-size, but that's somewhat context-dependent. Michael Hardy 03:46, 4 September 2006 (UTC)

[edit] df

Hi Michael,

I was thinking it could use a simple down to earth representation of this complex function using an example. If anyone else thinks so please let me know.

Linda

Hi I thought that a layman term would be best as most people int he talk section of the df think so, check it out.

LindaLindaGlass25 06:47, 4 September 2006 (UTC)