You really need to know the number of actual data points, which must come from the actual data. You should also know the experimental uncertainties of each point. Most standard procedures map the actual data to a uniform grid, sometimes with smoothing of the original data. Then the information content is lost. We are doing final testing on some general routines to address this and will make them available soon. -------------------------------------------------------------------------------------- Christopher Chantler, Professor, FAIP, Fellow American Physical Society Editor-in-Chief, Radiation Physics and Chemistry Chair, International IUCr Commission on XAFS President, International Radiation Physics Society School of Physics, University of Melbourne Parkville Victoria 3010 Australia +61-3-83445437 FAX +61-3-93474783 chantler@unimelb.edu.auhttps://owa.unimelb.edu.au/owa/redir.aspx?C=c7BoS0kVVkC1_S95-9x9l5cBu6YTjdAITgSrfUpfDAUV5oUH1LFYBcz08w8xvHMJoosZRdagfQM.&URL=mailto%3achantler%40unimelb.edu.au chantler@me.comhttps://owa.unimelb.edu.au/owa/redir.aspx?C=c7BoS0kVVkC1_S95-9x9l5cBu6YTjdAITgSrfUpfDAUV5oUH1LFYBcz08w8xvHMJoosZRdagfQM.&URL=mailto%3achantler%40me.com http://optics.ph.unimelb.edu.au/~chantler/xrayopt/xrayopt.htmlhttps://owa.unimelb.edu.au/owa/redir.aspx?C=c7BoS0kVVkC1_S95-9x9l5cBu6YTjdAITgSrfUpfDAUV5oUH1LFYBcz08w8xvHMJoosZRdagfQM.&URL=http%3a%2f%2foptics.ph.unimelb.edu.au%2f%7echantler%2fxrayopt%2fxrayopt.html http://optics.ph.unimelb.edu.au/~chantler/home.htmlhttps://owa.unimelb.edu.au/owa/redir.aspx?C=c7BoS0kVVkC1_S95-9x9l5cBu6YTjdAITgSrfUpfDAUV5oUH1LFYBcz08w8xvHMJoosZRdagfQM.&URL=http%3a%2f%2foptics.ph.unimelb.edu.au%2f%7echantler%2fhome.html ________________________________ From: Ifeffit on behalf of ifeffit-request@millenia.cars.aps.anl.gov Sent: Tuesday, 11 April 2017 3:00:02 AM To: ifeffit@millenia.cars.aps.anl.gov Subject: Ifeffit Digest, Vol 170, Issue 7 Send Ifeffit mailing list submissions to ifeffit@millenia.cars.aps.anl.gov To subscribe or unsubscribe via the World Wide Web, visit http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit or, via email, send a message with subject or body 'help' to ifeffit-request@millenia.cars.aps.anl.gov You can reach the person managing the list at ifeffit-owner@millenia.cars.aps.anl.gov When replying, please edit your Subject line so it is more specific than "Re: Contents of Ifeffit digest..." Today's Topics: 1. Information content from Athena for Hamilton test? (Will Bennett) 2. Re: Information content from Athena for Hamilton test? (Wayne Lukens) ---------------------------------------------------------------------- Message: 1 Date: Mon, 10 Apr 2017 13:59:36 +1000 From: Will Bennett To: ifeffit@millenia.cars.aps.anl.gov Subject: [Ifeffit] Information content from Athena for Hamilton test? Message-ID: Content-Type: text/plain; charset="utf-8" Hi everyone, Just a quick question regarding the "Information Content" output in Athena's LCF window. I've recently been playing around with using the Hamilton test (as outlined in Scott Calvin's book "XAFS for Everyone") to interrogate my combinatorics results. As many of you will know, this requires an estimate of the number of independent measurements in the data, in order to determine the degrees of freedom and subsequently the "a" value for computing the Lower Incomplete Beta Function. Would Athena's value for "Information Content" be appropriate to use as an estimate of the number of independent measurements in this case? How is this value of "Information Content" determined in Athena? Thanks in advance. Will