Tuesday, February 24, 2009

APCOM calling

One more acronym to remember! APCOM stands for Application of Computers and Operations Research in the Mineral Industry. It adds up and it stuck. My son knows a lot about EMF and I know a little about metrology in the mineral industry. We added it up and posted an abstract for our APCOM paper. We did so before the first deadline in 2008 came and went. APCOM is still calling for papers. Another deadline passed on February 15, 2009. Where have all those abstracts gone? Popular myth has it that abstracts always swamp program chairs. APCOM is to be held at Vancouver, British Columbia, Canada, from October 6 to 9, 2009. It 's high time to complete the program.

APCOM’s preliminary program brings up The Future of Mining and Technology’s Role. It doesn’t add up to another acronym but does have a futuristic ring to it. The first day is set aside for Resource Identification Estimation and Planning. That's a load of cool stuff. And it’s comes to my home turf in Vancouver, British Columbia. I would like to show resource planners how to estimate metal contents and grades of reserves and resources. It fits APCOM’s preliminary program like a silk glove. We wrote about it in 1991. We want to talk a bit more about it in 2009.

But wait a pixel-picking second! Where would our paper fit in? Geostatistics 1 on the first day? And Geostatistics 2 on the same day? Looks like Geostatistics for the Next Century all over again. That was quite a krige-and-smooth-fest. It took place at Montreal in 1993 with Chairperson Dimitrakopoulos in charge. At that time he was all wrapped up at the cutting edge of conditional simulation with voodoo variances. What I wanted to do was talk about The Properties of Variances. Nowadays, Dimitrakopoulos is Editor-in-Chief, Journal for Mathematical Geosciences. He is still teaching McGill’s students all he knows about conditional simulation. Despite the fact that signs of change to come are posted on IAMG’s website.

In fact, IAMG in 2009 is promoting mathematics, statistics and informatics. I couldn’t have made it up. No longer does it stand for International Association for Mathematical Geology but for International Association for Mathematical Geosciences. Its mission is “…to promote, worldwide, the advancement of mathematics, statistics and informatics in the Geosciences”. How about that? Agterberg, IAMG’s Past President, has yet to explain why his distance-weighted average point grade doesn’t have a variance. He might one day be asked under oath to explain whether or not his distance-weighted average point grade has a variance.

The following formula gives Agterberg's distance-weighted average point grade of his set of five (5) point grades. Agterberg's real problem is that this formula converges on the Central Limit Theorem if all weighting factors converge on 1/n.

It’s a bit of a stretch for Agterberg and his associates “…to promote…” statistics but declare null and void David’s “…famous Central Limit Theorem”. It doesn't take a genius to prove that the next formula converges on David's famous one when each wi converges on 1/n. The question is then what Agterberg was thinking in 1970 and in 1974. Surely, it's about time he rights his wrong!

I’m a stickler for unbiased sampling practices and sound statistics. So, I’m not at all surprised that scores of geoscientists would rather work with real statistics than with surreal geostatistics. After all, statisticians test for spatial dependence, chart sampling variograms, and count degrees of freedom. No hanky panky with the kriging game. No ifs and buts about degrees of freedom! No functions without variances. All scientists and engineers on our little planet should make sound statistics a way of life.

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