Author |
Message |
Pierre Dardenne (dardenne)
Senior Member Username: dardenne
Post Number: 53 Registered: 3-2002
| Posted on Thursday, December 02, 2010 - 3:04 pm: | |
Hi, concerning NIR validation, there is interesting information in ISO/12099. Pierre |
Howard Mark (hlmark)
Senior Member Username: hlmark
Post Number: 366 Registered: 9-2001
| Posted on Thursday, December 02, 2010 - 9:19 am: | |
Fernando - there is another, fairly new, ASTM standard, E2617 "Standard Practice for Validation of Empirically Derived Multivariate Calibrations" that should address some of your questions. It gives more information, and also specifies more stringent conditions than E1655 does, to ensure proper validation. Since it's new, it may still be undergoing revisions, so if you still have questions after reading E2617, send another question to this discussion thread and the primary authors of the Standards can address them (and possibly revise the standard based on your comments). Howard \o/ /_\ |
Fernando Morgado (fmorgado)
Junior Member Username: fmorgado
Post Number: 6 Registered: 12-2005
| Posted on Thursday, December 02, 2010 - 8:31 am: | |
Dear Sirs : I work during years in NIR and always I have a doubt about the correctly validation of a Model. I know is necesary have test samples, don�t outliers, measuring in the same conditions, etc. The real question is wich value calculate for to say this Model is validate. ASTM E 1655 say use minimum 20 samples and calculate T, if the T calculate is below a T table number with 95% confidence the Model is validate. The question is: If you have 20 test samples and the result NIR and LAB for that, how you can say the Model is validate. ( sample cover all the range of the model). For me R2, sec, sep, etc ara not a good procedure for decide if a model is validate or not. Some recomendations or comment. Thans Fernando Morgado |
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