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help for ^scrsize^                                                (version 1.0.4)
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Power for one sample screening study
------------------------------------

    ^scrsize^ tp_rate fp_rate, ^nd(^#^)^ ^ndb(^#^)^ ^tpn^ull^(^#^)^ ^fpn^ull^(^#^)^
         [^,^ ^a^lpha^(^#^)^ ^ns^im^(^#^)^ ^d^ots ^nodis^play ]

Description
-----------

^scrsize^ determines power to detect improvement relative to the joint fixed
   null true (^tpnull(^#^)^) and false positive (^fpnull(^#^)^) rates for a sample
   with the specified alternative rates (^tp_rate^ & ^fp_rate^) and specified
   sample sizes for diseased (^nd(^#^)^) and non-diseased (^ndb(^#^)^) subjects.

   Power is based on rejection of the null (tpr,fpr) relative to one-sided
   1-alpha joint (tpr,fpr) confidence regions for simulated samples drawn
   under the alternative true and false positive rates.  Joint confidence
   regions are rectangles with upper left corner 0,1 corner of the TPR, FPR
   unit square, and with right and lower sides comprised by lower TPR limit
   and upper FPR limit based on 1 - 2*(1-sqrt(1-alpha)) level exact 2-sided
   confidence limits for the component tpr and fpr.

   Null and alternative true and false positive rates should be specified as
   numbers between zero and one.

  returned results:  r(power)


Options
-------

^nsim(^#^)^ specifies the number of simulated study samples to be drawn for
   determination of power.  The default is 500 samples if not otherwise
   specified.

^alpha(^#^)^ specifies the type I error rate.  the default is
   1 - ($S_level/100.), i.e. .05 if the level has not been set.  See @level@

^nodisplay^ suppresses output display (in case where only returned results are
    desired).

^dots^ optionally displays a dot on the screen for each simulated sample drawn.


Remarks
-------

Persons interested in reproducibility of results should set the random-number
seed by typing set seed # before running ^scrtest^; see help @generate@.


References
----------


Author
------

        Gary Longton, Fred Hutchinson Cancer Research Ctr.
        glongton@@fhcrc.org


Also see
--------

 On line: help for @roctab@,  @emroc@ if installed,
          @rocsize@ if installed, @aucsize@ if installed,


