February, 2003
© 2000, 2001 Scott S. Emerson, M.D., Ph.D.
Session 3: 9
Schedule of Analyses
Example: Analyses after 40%, 60%, 80%, 100% (maintain maximal sample size)
Null: Theta <= 0         (size  = 0.025)
Alt : Theta >= 0.4888    (power = 0.975)
(Emerson & Fleming (1989) symmetric test)
STOPPING BOUNDARIES: Sample Mean scale
                            a      d
    Time 1 (N= 138.09) 0.1024 0.3864
    Time 2 (N= 207.14) 0.1733 0.3155
    Time 3 (N= 276.19) 0.2155 0.2732
    Time 4 (N= 345.23) 0.2444 0.2444