Unformatted text preview: h. PDF of t ( n − 1 ) f(t) area = p-value 0 t-statistic t To find a p‐value the Appendix Table of the t‐distribution does not give enough detail to get any accuracy. Therefore, the calculation of an exact p‐value requires special purpose statistical computing. The p‐value illustrated above can be calculated with Microsoft Excel with the function: TDIST(t‐statistic, degrees_of_freedom, 1) ↑ one-sided alternative 13 Chapter 10 Other forms of the alternative hypothesis have meaningful application. A problem may suggest testing the null hypothesis: H0 : μ ≥ a or H0 : μ = a against the alternative hypothesis: H1 : μ < a The test procedure uses the same test statistic as given in previous discussion – but the calculation of the p‐value is different. From the data set, calculate the sample mean x and sample variance s 2 . From these results, calculate the t‐test statistic: t= 14 x−a s
n Chapter 10 For a significance level α , the decision rule is to reject the null hypothesis H0 if: t < − tc where t c is...
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- Null hypothesis, H1, H.1