License
Users
- The license is valid for one named user (not a location).
Multiple machines
- Each copy of the program is a single user license.
- The person named on the license is welcome to install the program on TWO machines (for example, a desktop and laptop) provided that he/she is the only user of the software.
- Only one "lab computer" per license is permitted. If the program is installed on a lab computer, it cannot be installed on any other computers.
- You will need a separate unlock code for each machine, which we supply at no cost.
- If you replace an existing computer in the future we supply a new code at no cost.
License Term
Get an unlock code
- For information on how to obtain or use a code, click here.
Payment Policy
- Payment must be received in full before the unlock code is released.
(A purchase order is not a substitute for payment).
Refunds
- Refunds will not be issued after the program has been unlocked.
Bulk Licensing
- When purchasing multiple licenses, the lease starts the day the customer requests the FIRST unlock code. All leases will be set to expire one or two years from that date.
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"This software is great and the ease of use is amazing. I normally use [another program] and was prepared to spend hours...With your program I had the graphs in minutes and the graphs got it exactly right. An incredible effort. Thanks!!"
Ricardo Pietrobon - Director of Outcomes Research, Division of Orthopedic Surgery and Ambulatory Anesthesia, Duke University
Power and Precision
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Power and Precision is a statistical power analysis software package for calculation of a sample size for a planned study. The program features an unusually clear interface, and many tools to assist the user in developing an understanding of power analysis.