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Docente
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PALAGI LAURA
(programma)
1. Introduction.
Definition of learning systems. Goals and applications of machine learning (classification and regression). Basics on statistical learning theory (Vapnik
Chervonenkis bound). Underfitting and Overfitting. Use of data: training set, test set, validation set.
2. Artificial Neural Networks.
Neurons and biological motivation. Linear threshold units. The Perceptron and its learning algorithm (proof of convergence). Classification of linearly
separable patterns.
Multi-Layer Feedforward Neural Networks. Gradient method: basics. Back-propagation (BP) algorithm. BP batch version: proof of convergence and
choice of the learning rate. BP on-line version: incremental method, theorem of convergence. Momentum updating rule.
Radial-Basis function (RBF) networks: regularized and generalized RBF networks. Their use in interpolation and approximation. learning strategies and
error functions. Unsupervised selection of center. Supervised selection of weights and centers: decomposition methods into two blocks and decomposition methods into more blocks. Convergence theory of decomposition methods.
Early stopping
3. Support Vector Machines (Kernel methods)
Soft and hard Maximum Margin Classifiers. Quadratic programming formulation of the soft/hard maximum margin separators. Kernels methods.
Dual formulation of the primal QP problem. Wolfe duality theory for QP. KKT conditions. Frank Wolfe method: basics. Decomposition methods: SMO-type
algorithms, MVP algorithm, SVMlight, cyclic methods. Convergence theory. Implementation tricks: Caching, shrinking.
Choosing parameters: k-fold cross-validation. Multiclass SVM problems: one-against-one and one-against-all.
4. Practical use of learning algorithms.
5. Comparing learning algorithms from the optimization point of view.
6. Use of standard software (Weka, LIBSVM)
 Il materiale didattico è costituito da slide e note di lezioni.
Sono anche suggeriti i seguenti libri
Pattern Recognition and Machine Learning - Bishop - 2006
Deep Learning - Goodfellow, Bengio, Courville - 2016
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