Using the ARGUS detector at the e+e storage ring DORIS II, we have measured the Michel parameters , , and for ! l  decays in -pair events produced at center of mass energies in the region of the resonances. Using ! as spin analyzing tags, we nd e = 0:68 0:04 0:08, e = 1:12 0:20 0:09, e = 0:57 0:14 0:07, = 0:69 0:06 0:08, = 1:25 0:27 0:14 and = 0:72 0:18 0:10. In addition, we report the combine...

In the presence of nuisance parameters, we derive an explicit higher order asymptotic formula to compare the expected lengths of conndence intervals given by likelihood ratio statistics arising from the usual proole likelihood and various adjustments thereof. Highest posterior density regions, with approximate frequentist validity, are also included in the study.

For hypotheses of the type H0 : θ = θ0 vs H1 : θ 6= θ0 we demonstrate the equivalence of a Bayesian hypothesis test using a Bayes factor and the corresponding classical test, for a large class of models, which are detailed in the paper. In particular, we show that the role of the prior and critical region for the Bayes factor test is only to specify the type I error. This is their only role sin...