What are the coordinates of the following points in a CCD?
a. central point (Blue round sign)
b. the N axis point (Red round sign)
c. 2N-f factorial points located at the corners (Yellow round sign)
Does it change with the type of Distribution Function used (Gaussian or
Uniform?)
|
The PDDOEL documentation indicates the points are based on probability so the location would be based on the design variable distribution. If the variable has a gaussian distribution (PDVAR,,GAUS) then the probabilities will be based on a Gaussian distribution. If the variable is uniform (PDVAR,,UNIF) then the probabilities will be based on a uniform distribution. This can be verified by looking at the sample points used in the database (file.pds) or in the sample file (file.samp). For example, if a random variable has a gaussian distribution with mean of 10 and standard deviation of 1, the sample values will be at the following locations. Probability Level = .005 ( - 2.58 sigma ) => 7.42 Probability Level = .05 ( - 1.65 sigma) => 8.35 Probability Level = .50 ( 0 sigma) => 10.00 Probability Level = .95 ( +1.65 sigma) = 11.65 Probability Level = .995 ( +2.58 sigma) = 12.58 |
||
|