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Luis A. Afonso
Posts:
4,758
From:
LIsbon (Portugal)
Registered:
2/16/05


pvalue < alpha, correct to reject the Null!
Posted:
Oct 28, 2012 5:07 PM


Felt in the rejection interval, Firr
A few people angrily claim, that the pvalues commonly obtained in NHST are NOT, is even far away, what definition states: (From Wikipedia, the free encyclopedia): in statistical hypothesis testing, the pvalue is the probability of obtaining a test statistic at least as extreme as the one that was actually observed, assuming that the null hypothesis is true. ____________ Comment In fact, what all people do is to obtain a value that is simply pvalue = 1  F(z0), from F(z) , the Test Statistics Cumulative Distribution. Then if pvalue < alpha (a significance level chosen previously) we decide that the null hypotheses H0 is very unlike to be true; therefore we reject H0 in favour of Ha, the alternative one. Why do not change to pvalue to *firr* and keep the procedure: with the commonly chosen are only a 1/20 probability the *test* fall into the rejection interval if H0 is true. If it does we can be pratically sure that the null is false. (Down the pvalue, up the firr!)
Luis A. Afonso



