5 replies to this topic

[poppysnoss]

Hello.

I have a pile of chemistry results on proximate analysis (ash, moistures, fats, proteins and salts) that I have been carrying out for a project. However, I need to compile process control charts and work out uncertainty on these tests.

I am no statistical wizard and literally have no idea where to start. Does anyone have an excel format or similar that I could plunk results into and it magically comes up with something of statistical worth??? Or even point me in the direction of where I could find something of worth???

I am sorry if this message seems a bit vague at the moment. I have been pouring hours into trying to suss something out and seem to have melted my brain.

If anyone has any words of wisdom, I would be eternally grateful.

Many thanks

[Simon]

Try these Pops and then feel free to ask further clarification questions.

How to Control Charts
Quality Control Charts

Regards,
Simon

[poppysnoss]

Thankyou Simon, that is EXACTLY what I'm looking for - ie charts with upper and lower limits etc.

However, I still don't exactly know how to turn my data into one of these charts. (Sorry, feeling uber-fick at the moment!)

I need to have a good few reads through all this before anything is going to sink.

As I said, me and stats are not a good mix. Ask me anything about the sciencey-bit and I'll have a good go, this on the other hand....

Pops

[vassilis]

If you could share your raw data then i could give you some piece of advice...!!

[AS NUR]

dear poppysnoss.. you can use Kragten spreadsheet to count analytical chemistry uncertainty.. you can get the file of this measurement technic from EURACHEM / CITAC Guide CG 4..
Sorry can't attach the file in here (to big..)

[poppysnoss]

Oh, thankyou As nur.

I do actually have a copy of that document kicking around but hadn't picked out the Kragten information. Will have a perusal now....