Re: Bloody Johnny Foreigner

On 8 Aug, 18:31, Robert Henderson <phi...@xxxxxxxxxxxxxxxxxxxx> wrote:
In message <1186554684.391269.67...@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>, Gavin
Cawley <g...@xxxxxxxxxxxxx> writes



Oh yes we can. Imagine runs scored being two percent less or more. RH

You have just shown that you have no idea about tests for statistical
significance. The difference must be large in comparison with the
standard error of the mean (which depends on the variance and the
number of players) in order to be significant. Therefore there a 2%
difference may or may not be significant.

OK, the discussion has soared embarrassingly above your IQ yet again.
RH

No Robert. I am a scientist, I regularly use tests of statistical
significance in my work, I know how such tests are performed. Go ask
your professional statistician, he will tell you exactly what I have
told you.

You could always look it up on Wikipedia, the Student's [a great
English scientist that you have probably never heard of] t-test or
better still Welch's test

http://en.wikipedia.org/wiki/Student's_t-test

and

http://en.wikipedia.org/wiki/Welch%27s_t_test

if you don't like wiki, read the original article (I can post you a
copy if you can't get it on-line or from your library)

Welch, B. L. (1947), "The generalization of "student's" problem when
several different population variances are involved", Biometrika 34:
28-35

In any case, you will see that the test statistic involves the sample
variances.

.

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