OK, have I got a question for y'all! I'm teaching survival analysis and looking at Proportional Hazards Fit and Risk Ratios. In JMP 15 I'm getting a Prob>Chisq of <.0001 for my risk ratios (yes, it's an odd dataset where the differences in survival are rather large) with understandable 95% confidence limits. I've assumed this is testing the Ho that the risk ratio is not significantly different from a value of one. (Could be wrong there.) In JMP 16, however, evaluating the exact same data, I'm getting a Prob>Chisq of 0.9987 and zero for the lower 95% CI and nothing for the upper. Can anyone explain what is going on here?
