Dear Paul
I think you put that very well. >As far as I know (and I do NOT specialize in this), very few sets of RAW data are available for examination. I think this is correct. We have the spreadsheets - I have many different copies of the UCB/ETHOS WBT going back to 2003. By entering in the output data it is sometimes possible to work out what the numbers were in some cells and therefore make an updated calculation but not always. At a bare minimum we need a screenshot of the Test1-Test3 pages. It is then a matter of manually reproducing the entries. The problem with this approach is that the different versions of WBT 3.0 3.1 and 4.1.2 cannot be differentiated by looking at the Test pages. So it is not known which corrections have already been applied. It is much better to have the spreadsheet if one of those was used. As wood stove results have a high variability it is not possible to use one or two and get a meaningful guide about where it should be on a performance inventory chart. There are, or course, other tests in common use outside the USA. They either treat the raw data differently or they record different things and are not directly compatible or convertible. Were the calculated performance metrics between versions of tests not so different, based on the math alone, I would be tempted to say use the old ones as a general guide and start with the newest ideas and retain enough information to be able to update them. The situation is however not so favourable as the information provided is most frequently expected to tell the policy maker how much fuel a stove consumes from the environment. That being the case, the divergence is large, sometimes more than 250% of value. With Aprovecho, Berkeley, Colorado State, Univ of Johannesburg, the States of India and China and South Africa, the EU and various US states applying different understandings to the issue, whatever is agreed (which is always an interim solution) must be done with a clear notion of what the questions are and how such question are answered. >Well, having "older test results" possibly deemed NON-applicable would really shake up the stove evaluation situation. How old is "old"? Are the EPA Jetter-run tests already "old?" It was agreed in N Carolina this year that the current version (WBT 4.2.1) is valid for general use until updated again. This automatically defines any test performed using WBT 4.1.2 (pre-17 June 2012) or earlier 'old'. The same fuel consumption numbers used as input for previous versions are significantly (meaning more than 1 standard deviation) different, meaning 'detectably different'. That should settle the question of whether correcting forward is needed or not. If we are to still have a 'water boiling test only' as one complete tool, it requires several more corrections and the removal of invalid calculated numbers from the sheet so people stop reporting them as if they tell us something useful. The useful numbers should of course be retained. But prior to that we need to have a conversation about concepts - what the test is supposed to tell us and what to do to answer those questions. Paul, I appreciate the time you are putting into this. It is very important that these issues be discussed so ideas are solicited. Regards Crispin
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