s-news
[Top] [All Lists]

Re: Bug in s+seqtrial ?

To: <s-news@lists.biostat.wustl.edu>
Subject: Re: Bug in s+seqtrial ?
From: Abdulkadir Hussein <hussein@math.ualberta.ca>
Date: Sun, 25 Aug 2002 19:58:37 -0600 (MDT)
In-reply-to: <20020825143038.N7410-100000@sirius1.math.ualberta.ca>
Sorry. Please ignore  my previous e-mail regarding the bug in
s+seqtrial...
Actually, the code  was wrong in " alt.hypothesis=95 instead of
alt.hypothesis=c(105,95)..

Regards



On Sun, 25 Aug 2002, Abdulkadir Hussein wrote:

> Date: Sun, 25 Aug 2002 14:36:19 -0600 (MDT)
> From: Abdulkadir Hussein <hussein@math.ualberta.ca>
> To: s-news@lists.biostat.wustl.edu
> Subject: Bug in s+seqtrial ?
>
> Hi, to whoever is using s+seqtrial, the following code gives wrong
> scientific representation for the power (supposed to be "e-1"):
>
> seqDesign(prob.model = "normal", arms = 2, log.transform = F,
>       null.hypothesis = c(105, 105), alt.hypothesis = 95, variance
>        = c(324, 324), ratio = c(1, 1), nbr.analyses = 1, sample.size
>        = 138, test.type = "two.sided", power = "calculate", alpha =
>       0.025, epsilon = c(1, 1), design.family = seqScale(scaleType
>        = "X"), P = c(1, 1, 1, 1), R = c(0, 0, 0, 0), A = c(0, 0, 0,
>       0), display.scale = seqScale(scaleType = "X"))
>
> PROBABILITY MODEL and HYPOTHESES:
>    Two arm study of normally distributed response variable
>    Theta is difference in means (Treatment - Comparison)
>    Two-sided hypothesis test:
>            Null hypothesis : Theta =   0    (size  = 0.05    )
>     Alternative hypothesis : Theta < -10    (power = 8.797e-8)
>    (Fixed sample test)
>
> STOPPING BOUNDARIES: Sample Mean scale
>                           a       b      c      d
>     Time 1 (N= 138) -6.0064 -6.0064 6.0064 6.0064
>
>
>
>
> Regards
>
>
__________________________________________________________________
Abdulkadir Ahmed Hussein
Department of Mathematical Sciences
University of Alberta
Edmonton, Alberta
Canada T6G 2G1
Office: CAB 664
Phone: (403)436-4943
                W3: http://www.stat.ualberta.ca/~hussein

                Email: hussein@math.ualberta.ca
visit also: www.stat.ualberta.ca/~brg
___________________________________________________________________


<Prev in Thread] Current Thread [Next in Thread>