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katastrofa
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Re: Why?

March 7th, 2020, 5:04 pm

"I think that's the nub of the issue here. I believe that influence diagrams IDs mathematize and formalize Wright's path diagrams but I find it hard to believe these fancy graphs are explanations rather than a description/model of causation. They are 'just' CS data structures??"

In statistics, DAGs are just a systematic organisation of knowledge or believes about phenomena. They don't explain anything, because statistics isn't supposed to explain - it only helps to validate the researcher's theory/prior*. Still, such description was lacking in many places before Pearl, e.g. "explaining away", which his formalism explains in an intuitive way.

*I'm a hard-core Baysian. Not that I think that frequentists are wrong. They are right in some (trivial and useless) cases.
 
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Cuchulainn
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Re: Why?

March 8th, 2020, 12:37 pm

Could one conclude that AI is in a constant state of crisis if the various proponents cannot even agree on what a probability is?

Different tools for different models of 'reality'???

//
AI became hype again at the end of the 80s. In those days the West tried to emulate Japan's 5th Generation Project. AI was all symbolic and driven by Prolog. I actually invested $ in a knowledge-based in Prolog for CAD and CAM. This was the era of expert systems and symbolic computationSoon afterwards I switched to C++.
In 2000 then the next wave was intelligent and mobile agents, also based on KBS.
 
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katastrofa
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Re: Why?

March 8th, 2020, 2:42 pm

@"Different tools for different models of 'reality'???"

I believe so (unless you're Collector ;-D). Reality is a wicked problem: changeable, interconnected, context dependent. One tool can work only for a while. Then you have to tailor it or develop a new one.
 
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Collector
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Re: Why?

March 15th, 2020, 9:09 pm

As we all naturally agree on, numbers and number systems must be rooted in the physical world. One cannot store, send or even think about a number without using energy. Assume 1 is one energy unit and 0 is no energy (nothing). Then standard binary 8 is smaller than binary 3 

In addition time is money, get energy now is better than get energy tomorrow, so if numbers are sent from right to left then we have (Receiver and sender operates with clocks)
Screen Shot 2020-03-15 at 10.06.01 PM.png
is this well known? Standard binary is not an arbitrage free number system!  I will grab all threes, and stuck u with eights..

only when nominal value is considerably higher than number value I can not arb you. I swap 8 for 3 all day long, and all night long. Mathematicians will go bankrupt (except Oxford-P)?