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|    comp.ai.fuzzy    |    Fuzzy logic... all warm and fuzzy-like    |    1,275 messages    |
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|    Message 889 of 1,275    |
|    sthomas@fuzzastat.com to All    |
|    ANN: FASS Regression Solver: efficient f    |
|    27 Nov 15 08:46:52    |
      This is to announce the FASS Regression Solver. It is a product of The Fuzzy       Analytical & Statistical Software Co. Ltd. (FASS). It solves the general       (non-linear) regression problem.              FASS, as the name implies, is offering software in which there is intimate       mixing, yet careful separation, between uncertainty of the probabilistic kind,       and that of the fuzzy kind.               Uncertainty in the fitted parameters of the regression model is fuzzy. This is       in general the case for uncertainty regarding a constant known only to within       a fuzzy term of description. Uncertainty in the measured data is also       represented as fuzzy in        general. Thus the data inputs are fuzzy, and the estimated parameters reported       as outputs are fuzzy also. Both are standardized as LABR fuzzy sets. The error       residuals are assumed to be zero-mean Gaussian.              Consistent with the LABR fuzzy representation for each parameter, any function       of the parameters may likewise have its derived fuzzy uncertainty also       represented as an LABR fuzzy set. Thus the prediction function of the mean is       represented as a fuzzy        LABR swath, grosser or more precise according as the degree of fuzziness       inherent in the fitted parameters deriving from the model and the data.       Likewise, 5% and 95% probability quantiles are LABR fuzzy swaths w.r.t to the       independent variables.               The fuzzy mapping of the uncertainty in each parameter accomplishes in       principle that which the Bayesian approach seeks among others to do, which is       to map the marginals describing the uncertainty in each fitted parameter. But       it is insisted that the        proper calculus that should always have applied to uncertain constants is that       of the possibility calculus. The fundamental mathematical object of the       possibility calculus is the absolute likelihood function (a.l.f). Under this       calculus, the need for a        subjective, or any other "prior", is obviated.              This calculus is a special case of a reformulated fuzzy logic. Jaynes was       correct in his assertion that a logic that did not uphold Aristotle, where       Aristotle applies, could not be a proper basis for addressing the statistical       inference problem. The        fuzzy logic here deployed is one in which Aristotle is upheld. The       reformulated fuzzy logic allows for flexible connectives, and shows how,       within the theory, these may be selected. The max/min rules apply in some       situations, the product/product-sum        rules in others, and the bounded-sum rules in others, and in general, the       reformulated fuzzy logic proposes a linear combination of these three basic       rules, mediated through the semantic consistency coefficient. The       determination of the latter is        internal to the theory under a fairly straight-forward rule easy to motivate       and justify.              The probabiility of the data may be represented as a product-sum (p-s)       integral over the a.l.f. This provides an obvious maximization criterion (max       p-s) for the general regression problem. It is akin to maximum likelihood       obviously, but uses a product-       sum rule of disjunction rather than a maximization rule, or bounded-sum rule.       Both of the latter are rejected in the light of the reformulated fuzzy logic,       which reserves the maximum and bounded-sum rules of disjunction respectively       for cases where there        is strong positive, or strong negative semantic consistency. In the case of       statistical inference, it is a rule of semantic independence that must apply,       consistent with the i.i.d assumption for a statistical sample.               This approach obviates Bayesian priors, as already mentioned. It also       sidesteps the known difficulties of the maximum likelihood estimate (MLE) of       being sometimes misleading both as to location and precision of the true value       sought. And it may be used        to give a full mapping of the uncertainty in fitted parameters, as the       Bayesian approaches (e.g. MCMC) rightly seek to accomplish.              The FASS Regression Solver rests on the analytic extensions to ideas explored       in an earlier work, "Fuzziness and Probability" (1995). Those extensions are       forthcoming in a monograph, "The unified theory of fuzzy logic, the       possibility calculus, and        statistical inference, with application to Gaussian regression analysis".              See the website: http://fuzzastat.com, for further details of the FASS       Regression Solver.               For those interested, note in particular that a seminar/tutorial is proposed       for Jan 26-Feb 2, 2016, in Port of Spain, Trinidad.              Sidney       --       Dr. Sidney Thomas       Executive Chairman and Principal       The Fuzzy Analytical & Statistical Software Co. Ltd.       http://fuzzastat.com              --- SoupGate-Win32 v1.05        * Origin: you cannot sedate... all the things you hate (1:229/2)    |
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