Oct 19, 2007
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- More on decision trees
	- what to do with continuous-valued attributes?
		- binning strategies
	- what to do with missing attributes?
		- use probabilistic interpretations
		- read the book

- Next topic: neural networks

- Biological motivation and metaphor
        - axon
        - dendrites
        - processes taking place inside a neuron

- Models of artificial neurons
        - weighting different inputs;
        - summing; and
        - thresholding

- What are neurons capable of modeling
        - linear planes in hyperspace
                - e.g., AND in 2D space
                - e.g., OR in 2D space
                - not XOR (why?)

- Realization of classical gates in neurons
        - weights for AND gate
        - weights for OR gate

- Types of thresholding
	- use sign(x) for thresholding
	- sigmoid squashing perceptron
		- use 1/(1+e^(-x)) for thresholding
	- tanhx