Basic Concepts of Neural Networks The neurons in a neural network... Learning in ANNThe training procedure used by an artificial neural network... Learning in ANNA method of training art
Trang 1Chapter 8
Neural Networks for Data Mining
Trang 2Learning Objectives
Understand the concept and different types
of artificial neural networks (ANN)
Learn the advantages and limitations of
Trang 3Basic Concepts
of Neural Networks
Neural networks (NN)
Computer technology that attempts to
build computers that will operate like a
human brain The machines possess
simultaneous memory storage and works with ambiguous information
Trang 6The connection (where the weights are)
between processing elements in a neural
network
Trang 7Basic Concepts
of Neural Networks
Trang 8Basic Concepts
of Neural Networks
Trang 9historical cases
Trang 10Basic Concepts
of Neural Networks
The neurons in a neural network
Trang 11Basic Concepts
of Neural Networks
Trang 14In a neural network, the function that sums and transforms inputs before a neuron fires The relationship between the internal activation level and the output of a neuron
Trang 15Basic Concepts
of Neural Networks
Trang 16Basic Concepts
of Neural Networks
An S-shaped transfer function in the range of zero to one
A hurdle value for the output of a neuron to
trigger the next level of neurons If an output value is smaller than the threshold value, it will not be passed to the next level of neurons
The middle layer of an artificial neural network
Trang 17Basic Concepts
of Neural Networks
Trang 18Basic Concepts
of Neural Networks
Neural network architectures
algorithms include:
Trang 19Basic Concepts
of Neural Networks
Trang 20Basic Concepts
of Neural Networks
Trang 21Learning in ANN
The training procedure used by an artificial neural network
Trang 22Learning in ANN
Trang 23Learning in ANN
A method of training artificial neural networks in which sample cases are shown to the network
as input and the weights are adjusted to
minimize the error in its outputs
Trang 24Learning in ANN
A neural network architecture that uses
unsupervised learning
An unsupervised learning method created by Stephen Grossberg It is a neural network
architecture that is aimed at being more like in unsupervised mode
A type of neural network model for machine
Trang 25Learning in ANN
The general ANN learning process
Trang 26Learning in ANN
Trang 27Learning in ANN
The general ANN learning process
Trang 28Learning in ANN
The technique of matching an external pattern
to one stored in a computer’s memory; used in inference engines, image processing, neural computing, and speech recognition (in other words, the process of classifying data into
predetermined categories)
Trang 30historical cases
Trang 31Learning in ANN
How a network learns
parameters
working forward through the layers
output layer through the hidden layers
Trang 32Learning in ANN
Trang 33Developing Neural Network–Based Systems
Data collection and preparation
include all the attributes that are useful for solving the problem
Selection of network structure
The way in which neurons are organized in a neural network
Trang 34Developing Neural Network–Based Systems
Data collection and preparation
include all the attributes that are useful for solving the problem
Selection of network structure
Trang 35Developing Neural
Network–Based Systems
Trang 36Developing Neural Network–Based Systems
Learning algorithm selection
cover the training data and have the best predictive accuracy
Network training
set of weights and gradually enhances the fitness of the network model and the known data set
Trang 37Developing Neural Network–Based Systems
Testing
Comparing test results to actual results
well as potentially problematic situations
training set must be reexamined, and the training process may have to be repeated
Trang 38Developing Neural Network–Based Systems
Implementation of an ANN
other computer-based information systems and user training
developers are recommended for system improvements and long-term success
and management early in the deployment to
Trang 39Developing Neural
Network–Based Systems
Trang 40A Sample Neural Network Project
Trang 41Other Neural Network Paradigms
Hopfield networks
interconnectivity—each neuron is connected to every other neuron
previous values
constrained optimization problems, such as the classic traveling salesman problem (TSP)
Trang 42Other Neural Network Paradigms
Self-organizing networks
unsupervised mode
where neighborhoods of neurons are constructed
topologically close neurons are sensitive to similar inputs into the model
Trang 43Applications of ANN
ANN are suitable for problems whose
inputs are both categorical and numeric,
and where the relationships between inputs and outputs are not linear or the input data are not normally distributed