You can use Calc > Calculator to transform binomial data (proportions) or Poisson data (counts).
Binomial data (proportions)
You must have one column (or stored constant) for the number of trials (n) and one for the number of events (x). Trials must be positive integers, and events must be integers between 0 and n inclusive.
For example, suppose your number of trials are in C1, your number of events are in C2, and you want the transformations stored in C3.
1. Choose Calc > Calculator.
2. In Store result in variable, enter C3.
3. In Expression, enter FTP(C1,C2).
4. Click OK.
The FTP command uses the transformation:
(arcsin(sqrt(np/(n+1))) + arcsin(sqrt((np+1)/(n+1))))/2
Poisson data (counts)
You must have one column (or stored constant) for the counts, which must contain nonnegative integers.
For example, suppose the counts are in C4, and you want the transformations stored in C5.
1. Choose Calc > Calculator.
2. In Store result in variable, enter C5.
3. In Expression, enter FTC(C4).
4. Click OK.
The FTC command uses the transformation:
(sqrt(x)+sqrt(x+1))/2
References:
Bisgaard, Soren and Howard T. Fuller (1994) Quality Quandaries, Analysis of Factorial Experiments with Defects or Defectives as the Response, Quality Engineering, 7(2), 429-443.
Freeman, M.F. and J.W. Tukey (1950) Transformations Related to the Angular and the Square Root, Annals of Mathematical Statistics, 21(4), 607-611.