Path: utzoo!utgpu!watserv1!watmath!att!pacbell!pacbell.com!mips!apple!usc!elroy.jpl.nasa.gov!ames!dftsrv!hq!lgn!spoffojj From: spoffojj@hq.af.mil (Jason Spofford) Newsgroups: comp.ai.neural-nets Subject: Re: Observations on the State of NN theory Message-ID: Date: 28 Aug 90 01:28:01 GMT References: <3430013@hpwrce.HP.COM> Sender: news@hq.af.mil Lines: 36 In <3430013@hpwrce.HP.COM> kingsley@hpwrce.HP.COM (Kingsley Morse) writes: >I like the term "scale barrier". By the way, I wrote the GA so it would >randomly duplicate parts of the genetic code, in hopes of "repeating whole >structures or putting them together in different ways". Biological GAs >call it duplication mutation. I may have done it wrong though, because >the resultingly "stiff" brain was still thwarted by the "scale barrier". I was hoping you could expand a little on the GA/NN process you implemented. Do you evolve NN structures that are then subjected to a specific training algorithm, or do you evolve weights for a fixed structure or do you evolve both the weights and the structure? I have not reached the "scale barrier" as you mentioned. Perhaps it is because my problems are too small. What size/typeproblems are you attempting to solve? It could be that this scale barrier is a product of the scalability of the training algorithm (assuming you use one). On another note, I find the discussion on the brain's architecture very interesting. It's my OPINION that there are many types of neurons in biological systems. Some lend themselves to fixed behaviors and are relatively untrainable. For instance, neurons that control reflex actions. The genetic code must contain specific behaviors and connections for these neurons. On the other hand, some neurons are somehow influenced by training processes. They have very non-specific connections and behaviors. They are designed to be influenced by the environment and possibly by "Instructor" neurons. The genetic code in this instance does not directly encode behavior, it just sets the stage by which the behavior can be set or unset. Any other opinions? -- ---------------------------------------------------------- ) Jason Spofford The AF LAN Manager ( ) spoffojj@hq.af.mil George Mason Univ. Grad. Stud. ( ----------------------------------------------------------