Compute Probabilities Given Bounds and Drift

This program computes probabilities given bounds and drift.  It is based upon the Lan-DeMets method, and allows computation of boundaries at any time during the monitoring of a study. It is valid for any normal test statistic with independent increments. The information time is the ratio of accrued sample size to the total sample size for normal data.

Number of interim analyses
Equally spaced times between 0 and 1 Yes   No
Information Times: (>0 & <=1)
Overall significance level? (>0 and <=1)
One, two-sided symmetric or asymmetric? One   Two  Asymmetric
Type of spending function
Do you wish to truncate the standardized bounds? Yes   No
Do you wish to use drift parameters? Yes   No
How many drift parameters?
Enter drift parameters

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