stem/AI/Neural Networks/SLP/Perceptron Convergence.md
andy d7ab8f329a vault backup: 2023-06-05 17:01:29
Affected files:
Money/Assets/Financial Instruments.md
Money/Assets/Security.md
Money/Markets/Markets.md
Politcs/Now.md
STEM/AI/Neural Networks/CNN/Examples.md
STEM/AI/Neural Networks/CNN/FCN/FCN.md
STEM/AI/Neural Networks/CNN/FCN/FlowNet.md
STEM/AI/Neural Networks/CNN/FCN/Highway Networks.md
STEM/AI/Neural Networks/CNN/FCN/ResNet.md
STEM/AI/Neural Networks/CNN/FCN/Skip Connections.md
STEM/AI/Neural Networks/CNN/FCN/Super-Resolution.md
STEM/AI/Neural Networks/CNN/GAN/DC-GAN.md
STEM/AI/Neural Networks/CNN/GAN/GAN.md
STEM/AI/Neural Networks/CNN/GAN/StackGAN.md
STEM/AI/Neural Networks/CNN/Inception Layer.md
STEM/AI/Neural Networks/CNN/Interpretation.md
STEM/AI/Neural Networks/CNN/Max Pooling.md
STEM/AI/Neural Networks/CNN/Normalisation.md
STEM/AI/Neural Networks/CNN/UpConv.md
STEM/AI/Neural Networks/CV/Layer Structure.md
STEM/AI/Neural Networks/MLP/MLP.md
STEM/AI/Neural Networks/Neural Networks.md
STEM/AI/Neural Networks/RNN/LSTM.md
STEM/AI/Neural Networks/RNN/RNN.md
STEM/AI/Neural Networks/RNN/VQA.md
STEM/AI/Neural Networks/SLP/Least Mean Square.md
STEM/AI/Neural Networks/SLP/Perceptron Convergence.md
STEM/AI/Neural Networks/SLP/SLP.md
STEM/AI/Neural Networks/Transformers/LLM.md
STEM/AI/Neural Networks/Transformers/Transformers.md
STEM/AI/Properties.md
STEM/CS/Language Binding.md
STEM/Light.md
STEM/Maths/Tensor.md
STEM/Quantum/Orbitals.md
STEM/Quantum/Schrödinger.md
STEM/Quantum/Standard Model.md
STEM/Quantum/Wave Function.md
Tattoo/Music.md
Tattoo/Plans.md
Tattoo/Sources.md
2023-06-05 17:01:29 +01:00

42 lines
2.1 KiB
Markdown

Error-Correcting Perceptron Learning
- Uses a McCulloch-Pitt neuron
- One with a hard limiter
- Unity increment
- Learning rate of 1
If the $n$-th member of the training set, $x(n)$, is correctly classified by the weight vector $w(n)$ computed at the $n$-th iteration of the algorithm, no correction is made to the weight vector of the perceptron in accordance with the rule:
$$w(n + 1) = w(n) \text{ if $w^Tx(n) > 0$ and $x(n)$ belongs to class $\mathfrak{c}_1$}$$
$$w(n + 1) = w(n) \text{ if $w^Tx(n) \leq 0$ and $x(n)$ belongs to class $\mathfrak{c}_2$}$$
Otherwise, the weight vector of the perceptron is updated in accordance with the rule
$$w(n + 1) = w(n) - \eta(n)x(n) \text{ if } w^Tx(n) > 0 \text{ and } x(n) \text{ belongs to class }\mathfrak{c}_2$$
$$w(n + 1) = w(n) + \eta(n)x(n) \text{ if } w^Tx(n) \leq 0 \text{ and } x(n) \text{ belongs to class }\mathfrak{c}_1$$
1. _Initialisation_. Set $w(0)=0$. perform the following computations for
time step $n = 1, 2,...$
2. _Activation_. At time step $n$, activate the perceptron by applying continuous-valued input vector $x(n)$ and desired response $d(n)$.
3. _Computation of Actual Response_. Compute the actual response of the perceptron:
$$y(n) = sgn[w^T(n)x(n)]$$
where $sgn(\cdot)$ is the signum function.
4. _Adaptation of Weight Vector_. Update the weight vector of the perceptron:
$$w(n+1)=w(n)+\eta[d(n)-y(n)]x(n)$$ where
$$
d(n) = \begin{cases}
+1 &\text{if $x(n)$ belongs to class $\mathfrak{c_1}$}\\
-1 &\text{if $x(n)$ belongs to class $\mathfrak{c_2}$}
\end{cases}
$$
5. _Continuation_. Increment time step $n$ by one and go back to step 2.
- Guarantees convergence provided
- Patterns are linearly separable
- Non-overlapping classes
- Linear separation boundary
- Learning rate not too high
- Two conflicting requirements
1. Averaging of past inputs to provide stable weight estimates
- Small eta
2. Fast adaptation with respect to real changes in the underlying distribution of process responsible for $x$
- Large eta
![slp-separable](../../../img/slp-separable.png)