Re: [Ifeffit] How to calculate F-value for XANES PCA results

2010-01-11 Thread Wayne Lukens
Hi Andrew, I don't completely understand what your question is, but I will try to answer you. First, Sam Webb should be able to answer exactly how F was calculated in Six-Pack. However, I can tell you how F is calculated in general. First of all, the number in the Excel spread-sheet is probably

Re: [Ifeffit] How to calculate F-value for XANES PCA results

2010-01-11 Thread Andrew
Hi everyone, Thank you Dr. Lukens for your help! Let me see if I understand the method that was described for the F-value for the variances using the Fernandez-Garcia definition (that was previously mentioned), and please correct me if I am mistaken. The Principal Component Analysis

Re: [Ifeffit] How to calculate F-value for XANES PCA results

2010-01-11 Thread Wayne Lukens
Hi Andrew, It is easier to use Fdist to calculate the probability that a given value of F corresponds is within the noise. The way to do this is to use FDIST(F, (v1-v2), v1), where F, v1, and v2 are explained below. If you have two models, model 1 and model 2, where model 1 has an additional