Our research group in Brazil is having questions about PB desings, since we are not experts on this tool
years ago, we have acquired que Software Statistica 10, from statsoft. But a Dr. in Brazil claims the PB matrix on the software is wrong, because it differs from the original paper PB. It's my opinion that they would not make such mistake, since there are so many papers with different PB matrix. I have always designed PB using this software and I am afraid to ask, was all my experiments wrong then?
The matrix from the software in a 16 run PB is:
Standard Design: 2**(15-11) design (Spreadsheet1)
A B C D E F G H I J K L M N O
1 -1 -1 -1 -1 1 1 1 1 1 1 -1 -1 -1 -1 1
2 -1 -1 -1 1 1 1 -1 1 -1 -1 -1 1 1 1 -1
3 -1 -1 1 -1 1 -1 1 -1 1 -1 1 -1 1 1 -1
4 -1 -1 1 1 1 -1 -1 -1 -1 1 1 1 -1 -1 1
5 -1 1 -1 -1 -1 1 1 -1 -1 1 1 1 -1 1 -1
6 -1 1 -1 1 -1 1 -1 -1 1 -1 1 -1 1 -1 1
7 -1 1 1 -1 -1 -1 1 1 -1 -1 -1 1 1 -1 1
8 -1 1 1 1 -1 -1 -1 1 1 1 -1 -1 -1 1 -1
9 1 -1 -1 -1 -1 -1 -1 1 1 1 1 1 1 -1 -1
10 1 -1 -1 1 -1 -1 1 1 -1 -1 1 -1 -1 1 1
11 1 -1 1 -1 -1 1 -1 -1 1 -1 -1 1 -1 1 1
12 1 -1 1 1 -1 1 1 -1 -1 1 -1 -1 1 -1 -1
13 1 1 -1 -1 1 -1 -1 -1 -1 1 -1 -1 1 1 1
14 1 1 -1 1 1 -1 1 -1 1 -1 -1 1 -1 -1 -1
15 1 1 1 -1 1 1 -1 1 -1 -1 1 -1 -1 -1 -1
16 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
While the Orginal PB is the picture I've attached.
My question is, is there different ways to make a PB matrix, I have seen different papers with the original orthogonal PB matrix from Plackett and Burman paper, with all -1 (low value) on the last experiment like the image, and papers will all positive (high value) first run, like this handbook.
http://www.itl.nist.gov/div898/handbook/pri/section3/pri335.htm
Wikipedia on PB also shows a different matrix.
Please forgive my ignorance, but I was hoping for some guidance from someone who knows better than I do on this type of designs.
Thank you so much for your time.
Sincerely
Dr. Paulo Marcelo Avila Neto