On Tue, Sep 9, 2008 at 4:27 AM, Pei Wang <[EMAIL PROTECTED]> wrote: > Sorry I don't have the time to type a detailed reply, but for your > second point, see the example in > http://www.cogsci.indiana.edu/pub/wang.fuzziness.ps , page 9, 4th > paragraph: > > If these two types of uncertainty [randomness and fuzziness] are > different, why bother to treat them in an uniform way? > The basic reason is: in many practical problems, they are involved > with each other. Smets stressed > the importance of this issue, and provided some examples, in which > randomness and fuzziness are > encountered in the same sentence ([20]). It is also true for > inferences. Let's take medical diagnosis > as an example. When a doctor want to determine whether a patient A is > suffering from disease D, > (at least) two types of information need to be taken into account: (1) > whether A has D's symptoms, > and (2) whether D is a common illness. Here (1) is evaluated by > comparing A's symptoms with D's > typical symptoms, so the result is usually fuzzy, and (2) is > determined by previous statistics. After > the total certainty of "A is suffering from D" is evaluated, it should > be combined with the certainty > of "T is a proper treatment to D" (which is usually a statistic > statement, too) to get the doctor's > "degree of belief" for "T should be applied to A". In such a situation > (which is the usual case, > rather than an exception), even if randomness and fuzziness can be > distinguished in the premises, > they are mixed in the middle and final conclusions.
Thanks, that's a good point that I haven't thought of. For example I have a _slight_ knee pain (fuzzy, z = 0.6) knee pain -> rheumatoid arthritis (p = 0.3) (excuse me for making up numbers) Then my system would convert knee pain (z = 0.6) to knee pain = true (binary) and conclude rheumatoid arthritis (p = 0.3) So there is some loss of information, but I feel this is OK. Many commonsense reasoning steps are lossy. We're not trying to build doctors here. A commonsense AGI can control a medical expert system to achieve professional levels. The point is, I can always keep P and Z orthogonal. YKY ------------------------------------------- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244&id_secret=111637683-c8fa51 Powered by Listbox: http://www.listbox.com