Manually calculate a p-value | How to find p-value in t test
Thep-valueiscalculatedusingthesamplingdistributionoftheteststatisticunderthenullhypothesis,thesampledata,andthetypeoftestbeingdone(lower-tailedtest,upper-tailedtest,ortwo-sidedtest).Thep-valuefor:alower-tailedtestisspecifiedby:p-value=P(TSts|H0istrue)=cdf(ts)anupper-tailedtestisspecifiedby:p-value=P(TSts|H0istrue)=1-cdf(ts)assumingthatthedistributionoftheteststatisticunderH0issymmetricabout0,atwo-sidedtestisspecifiedby:p-value=2*P(TS|ts||H0istrue)=2*(1-cdf(|ts|))Where:PProbabilityofaneventTS...
The p-value is calculated using the sampling distribution of the test statistic under the null hypothesis, the sample data, and the type of test being done (lower-tailed test, upper-tailed test, or two-sided test).
The p-value for: a lower-tailed test is specified by: p-value = P(TS ts | H0 is true) = cdf(ts) an upper-tailed test is specified by: p-value = P(TS ts | H0 is true) = 1 - cdf(ts) assuming that the distribution of the test statistic under H0 is symmetric about 0, a two-sided test is specified by: p-value = 2 * P(TS |ts| | H0 is true) = 2 * (1 - cdf(|ts|)) Where: P Probability of an event TS Test statistic ts observed value of the test statistic calculated from your sample cdf() Cumulative distribution function of the distribution of the test statistic (TS) under the null hypothesisMinitab automatically displays p-values for most hypothesis tests. But you can also use Minitab to “manually” calculate p-va...