They do it through market research. I have no idea how the numbers are actually calculated or what they really are. I'm going to make up a hypothesis here.

MS uses some statistical calculations to determine the number of random samples needed to get the information they want. They then randomly select that number of MSDN subscribers and contact them to take a survey.

Let's say 10% say they use VFP....then 10% of future sales will be credited to VFP. They don't care specifically what John Doe uses.

I have participated in both online and telephone surveys from MS. I can't say they were done to determine my MSDN usage, but I can't say they weren't either. I do know that I have been asked what my primary and secondary development tools are.


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>I'd say it's because of you buying history. But what about others? That's unexplainable. How could they tell that John Doe buying an MS MDSN Universal package for the first time and not only that but that John Does has never bought anything from MS before. So perhaps John Does first wanted to buy VFP but when he saw all he could get by investing a reasonable amount of money he decided to get MSDN instead.
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>For those case how do they interpret that sale?
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>Now way to do it. The official answer will probably look like "We have internal procedures that are followed so that we can establish the field of interests or our customers bla bla bla..."
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>So you'll get a politically correct answer. No way they'll ever tell you "No fu**ing way we can figure that out"
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>I'll believe an answer when I see numbers, a formula. In a word something logic besides words.