Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!ames!ncar!boulder!sunybcs!sybil!jagota From: jagota@sybil.cs.buffalo.edu (Arun Jagota) Newsgroups: comp.ai.neural-nets Subject: Re: : Step Function Keywords: learning,generalization Message-ID: <10167@eerie.acsu.Buffalo.EDU> Date: 12 Sep 89 14:40:04 GMT References: <1060@rex.cs.tulane.edu> <6980@sdcsvax.UCSD.Edu> <17538@bellcore.bellcore.com> <1727@cbnewsl.ATT.COM> <7011@sdcsvax.UCSD.Edu> <11308@boulder.Colorado.EDU> Sender: nobody@acsu.buffalo.edu Reply-To: jagota@sybil.UUCP (Arun Jagota) Organization: SUNY @ Buffalo Lines: 20 In article <11308@boulder.Colorado.EDU> bill@synapse.Colorado.EDU (Bill Skaggs) writes: > > Is it necessary to have a bias in order to be able to learn? > > Not always. If the training set includes an example of every >possible input, then the device only needs to be able to "memorize" >the correct responses -- it doesn't need a preset bias. > Even then, it might be *useful* to consider the complexity of the representation (the functional form) of the learned function that the device forms. A device will exhibit good functional form learning ability if it forms a *good* representation. Since what constitutes the *best* representation (min # of params, length of representation in bits, etc) is a subjective matter, this amounts to needing a bias. Moreover, an unbiased representation will be a table look-up which has no generalisation capability (whereas a *better* representation should have some generalisation capability). CSNET : jagota@cs.buffalo.edu BITNET : jagota@sunybcs