« on: June 07, 2009, 02:41:34 AM »
Thanks again, but my last post was on a different example. There are NO conditions or instructions other than to diagram the fact that Y is examined before X and Z are examined. It tells us only that there are 6 total examinations, and, like you said, no information as to whether perhaps 1 might occur on separate occasions.
I'm not sure whether those 4 scenarios that you typed up pertain to my last post, or my original post. The variables you chose and language are mixed up.
At any rate, I'm about to send you the pages that I'm talking about. You'll see what I mean then.
IMAGES HERE: http://picasaweb.google.com/changesmyweltanschauung/Powerscore#5344435170144698690
Scenario D above fits this example, using the same variables. C and D mimic the example you posted, just demonstrating why whether they can occur simultaneously or not does not lead to what you think it does. I just looked at the page. They are off in having ~Y in the last two, if X and Z can occur together.
The elimination of X and Z from the first slot and not the second though is not a recognition that they can occur together. That would still be the case, whether they can occur together or only separately.
"They DO recognize that X and Z could occur together in the second slot, and so just eliminate the possibility of them occurring first" <<<<<< That is where you are confusing yourself. They eliminate it from the first slot only, regardless whether X and Z can occur together or not.
Work it out on paper. Put Y in slot one. Slot two can be filled with X or Z or both. You can't eliminate them as possibilities for slot 2. That's true whether they can occur at the same time or not. That's why they aren't having you eliminate them from slot two.