30.5 \(P\)-values: Two independent means
A \(P\)-value is needed to determine if the sample statistic is consistent with the assumption. Since the \(t\)-score is large, the \(P\)-value will be small using the 68–95–99.7 rule. This is confirmed by the software (jamovi: Fig. 30.1; SPSS: Fig. 30.2): the two-tailed \(P\)-value is \(0.011\). The small \(P\)-value suggests that the observations are inconsistent with the assumption (Table 28.1).
Click on the hotspots in the following image, to see what the SPSS output tells us.