This article characterizes the set of activation functions, bounded or unbounded, that allow feedforward network approximation of the continuous functions on the classic two-point compactification of R 1 . The characterization fails when the set of targets are continuous functions on the classic com
On the approximate realization of continuous mappings by neural networks
โ Scribed by Ken-Ichi Funahashi
- Publisher
- Elsevier Science
- Year
- 1989
- Tongue
- English
- Weight
- 733 KB
- Volume
- 2
- Category
- Article
- ISSN
- 0893-6080
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โฆ Synopsis
In this paper, we prove that any continuous mapping can be approximately realized by Rumelhart-Hinton-Williams' multilayer neural networks with at least one hidden layer whose output functions are sigmoid functions. The starting point of the proof for the one hidden layer case is an integral formula recently proposed by Irie-Miyake and from this, the general case (for any number of hidden layers) can be proved by induction. The two hidden layers case is proved also by using the Kolmogorov-Arnold-Sprecher theorem and this proof also gives non-trivial realizations.
๐ SIMILAR VOLUMES
In this paper, we prove that any finite time trajectory of a given n-dimensional dynamical system can be approximately realized by the internal state of the output units of a continuous time recurrent neural network with n output units, some hidden units, and an appropriate initial condition. The es
I4~, study the approximation o.f continuous mappings and dichotomies by one-hidden-layer networks from a computational point of view Our approach is based on a new approximation method specially designed for constructing "small networks. We give upper bounds on the size o.f these networks.
For the nearly exponential type of feedforward neural networks (neFNNs), the essential order of their approximation is revealed. It is proven that for any continuous function defined on a compact set of R(d), there exist three layers of neFNNs with the fixed number of hidden neurons that attain the