a bug with Student t-value??
Sunny Srivastava wrote:
Hi Huaru, Are you sure you are looking at 0.95 and NOT 0.975? as qt(0.975,9) = 2.262 generally tables are given for alpha/2 (alpha=0.05 in your case) significance. Please check carefully.
Or, put differently, tables are often given for two-sided p-values (especially in the back pages of textbooks), whereas qt() is for one-sided. I.e. the t distribution with 9 DF has a probability of 0.95 of falling BELOW 1.833 but also of falling BETWEEN -2.262 and +2.262.
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