Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Deep Learning 
Baptiste Wicht 
baptiste.wicht@gmail.com 
September 12, 2014 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Table of Contents 
1 Deep Learning 
2 Restricted Boltzmann Machine 
3 Deep Belief Network 
4 Convolutional RBM 
5 Convolutional DBN 
6 Conclusion 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
History 
Usages 
Difficulties 
Contents 
1 Deep Learning 
Definition 
History 
Usages 
Difficulties 
2 Restricted Boltzmann Machine 
3 Deep Belief Network 
4 Convolutional RBM 
5 Convolutional DBN 
6 Conclusion 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
History 
Usages 
Difficulties 
Definition 
Deep Learning (Wikipedia) 
Deep learning is a set of algorithms in machine learning that 
attempt to model high-level abstractions in data by using model 
architectures composed of multiple non-linear transformations 
Deep Learning (deeplearning.net) 
Deep Learning is a new area of Machine Learning research, which 
has been introduced with the objective of moving Machine 
Learning closer to one of its original goals: Artificial Intelligence. 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
History 
Usages 
Difficulties 
Definition (cont.d) 
Goal: Imitate the nature 
Set of algorithms 
Generally structures with multiple layers 
Often unsupervised feature learning 
Time-consuming training 
Sometimes large amount of data 
Generally complex data 
New name for an old thing 
hot topic 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
History 
Usages 
Difficulties 
History 
1960: Neural networks 
1985: Multilayer Perceptrons 
1986: Restricted Boltzmann Machine 
1995: Support Vector Machine 
2006: Hinton presents the Deep Belief Network (DBN) 
New interests in deep learning and RBM 
State of the art MNIST 
2009: Deep Recurrent Neural Network 
2010: Convolutional DBN 
2011: Max-Pooling CDBN 
Many competitions won and state of the art results 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
History 
Usages 
Difficulties 
Names 
Geoffrey Hinton 
Andrew Y. Ng 
Yoshua Bengio 
Honglak Lee 
Yann LeCun 
... 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
History 
Usages 
Difficulties 
Algorithms 
Deep Neural Networks 
Deep Belief Networks 
Convolutional Deep Belief Networks 
Deep SVM 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
History 
Usages 
Difficulties 
Usages 
Text recognition 
Facial Expression Recognition 
Object Recognition 
Audio classification 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
History 
Usages 
Difficulties 
Difficulties 
Large number of free variables 
Few insights on how to set them 
Complex to implement 
Large variations between papers 
Lot of refinements were proposed 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Contents 
1 Deep Learning 
2 Restricted Boltzmann Machine 
Definition 
Training 
Units 
Variants 
3 Deep Belief Network 
4 Convolutional RBM 
5 Convolutional DBN 
6 Conclusion 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Definition 
Restricted Boltzmann Machine 
Function: Learn a probability distribution over the input 
Generative stochastic neural network 
Visible and hidden neurons 
Neurons form a bipartite graph 
V visible units and visible biases 
H hidden units and hidden biases 
VxH weights 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Definition (Cont.d) 
Binary units (Bernoulli RBM) 
p(hj = 1|v) = (cj + 
mX 
i 
viwi,j ) 
p(vi = 1|h) = (bi + 
nX 
j 
hjwi,j ) 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Example 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Example 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Example 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Example 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Example 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Usages 
Unsupervised feature learning 
Classification with other techniques (linear classifier, SVM, ...) 
Limited to one layer of abstraction 
Stacking for higher-level models and classification 
Deep Belief Network 
Deep Boltzmann Machines 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Training 
Objective: Maximizing the log-likelihood 
Intractable 
Other methods have been developed: 
Markov Chain Monte Carlo (MCMC) (Too slow) 
Contrastive Divergence (CD) (Hinton) 
Persistent CD 
Mean-Field CD (mf-CD) 
Parallel Tempering 
Annealed Importance Sampling 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Contrastive Divergence 
For each data point 
1 Compute gradients g between t = k and t = k − 1 
2 Add   g to the weights and the biases 
Repeat for several epochs 
Experiments have shown that CD1 (k = 1) works well 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Contrastive Divergence 
When to stop training ? 
1 Proxies to log-likelihood: 
Reconstruction error 
Pseudo-likelihood (PCD) 
2 Visual inspection of the filters 
Training is relatively fast 
Can be trained on GPU 
Hard to compare two RBMs 
Hard to test an implementation correctly 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Contrastive Divergence Options 
Mini-batch training 
Momentum 
Weight decay 
Sparsity Target 
... 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Units 
RBM Was initially developed with binary units 
Different types of units can be used: 
Gaussian visible units for real-value inputs 
Softmax hidden unit for classification (last layer) 
Rectified Linear Unit (ReLU) units for hidden/visible 
Can be capped 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Units 
Variants 
Variants 
Convolutional RBM (see later) 
mean-covariance RBM (mcRBM) 
Sparse RBM (SRBM) 
Third-Order RBM 
Spike And Slab RBM 
Nonnegative RBM 
... 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Contents 
1 Deep Learning 
2 Restricted Boltzmann Machine 
3 Deep Belief Network 
Definition 
Training 
4 Convolutional RBM 
5 Convolutional DBN 
6 Conclusion 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Definition 
Deep Belief Network 
Generative graphical model 
Type of Deep Neural Network 
Multiple layer of hidden units 
Stack of RBMs 
Can be implemented with other autoencoders 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Definition (Cont.d) 
Each RBM takes input 
from previous layer output 
Each layer forms a 
higher-level representation 
of the data 
Number of hidden units in 
each layer can be tuned 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Training 
1 Train each layer, from bottom to top, with Contrastive 
Divergence (Unsupervised) 
2 Then treat the DBN as a MLP 
3 If necessary, fine-tune the last layer for classification 
(Supervised) 
Back propagation 
nonlinear Conjugate Gradient method 
Limited Memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) 
Hessian-Free CG (Martens) 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Probabilistic Max Pooling 
Contents 
1 Deep Learning 
2 Restricted Boltzmann Machine 
3 Deep Belief Network 
4 Convolutional RBM 
Definition 
Training 
Probabilistic Max Pooling 
5 Convolutional DBN 
6 Conclusion 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Probabilistic Max Pooling 
Definition 
Convolutional RBM 
Motivation: Translation-invariance 
Scaling to full-size images 
Variant of RBM, concepts remain the same 
NV xNV binary visible units 
K groups of hidden units 
NKxNK binary hidden units per group 
Each group has a NWxNW filter (NW , NV − NH + 1) 
A bias bk for each hidden group 
A single bias c for all visible units 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Probabilistic Max Pooling 
Definition (Cont.d) 
Binary units: 
p(hk 
j = 1|v) = (bk + (W~ k v v)j ) 
p(vi = 1|h) = (c + 
KX 
k 
(Wk f hk )i) 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Probabilistic Max Pooling 
Training 
Contrastive Divergence 
Gradients computations are done with convolutions 
Same refinements can be used (weight decay, momentum, ...) 
CRBM is highly overcomplete 
Sparse learning is very important 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Probabilistic Max Pooling 
Probabilistic Max Pooling 
Shrink the representation by a constant factor C 
Allows higher-level to be invariant to small translations 
Reduces computational effort 
Generative version of standard Max Pooling 
Pooling layer with K groups of pooling units 
Each group has NPxNP units 
NP , NH/C 
Each hidden block  (CxC) is connected to exactly one 
pooling unit 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Training 
Probabilistic Max Pooling 
Definition (Cont.d) 
Binary units: 
p(vi = 1|h) = (c + 
KX 
k 
(Wk f hk )i) 
I(hk 
j ) , bk + (W~ k v v)j 
p(hk 
j = 1|v) = 
exp(I(hk 
i )) 
1 + 
P 
j02
exp(I(hk 
i0)) 
p(pk 
= 0|v) = 
1 
1 + 
P 
j02
exp(I(hk 
i0)) 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Contents 
1 Deep Learning 
2 Restricted Boltzmann Machine 
3 Deep Belief Network 
4 Convolutional RBM 
5 Convolutional DBN 
6 Conclusion 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Definition 
Stack of Convolutional RBM 
With or without Probabilistic 
Max Pooling 
Each RBM takes input from 
previous layer output 
Each layer forms a higher-level 
representation of the data 
Number of hidden units in each 
layer can be tuned 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Feature Learning 
Source: Honglak Lee 
Each layer learns a different 
abstraction of features 
1 Stroke 
2 Parts of faces 
3 Faces 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Implementation 
Conclusion 
Contents 
1 Deep Learning 
2 Restricted Boltzmann Machine 
3 Deep Belief Network 
4 Convolutional RBM 
5 Convolutional DBN 
6 Conclusion 
Implementation 
Conclusion 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Implementation 
Conclusion 
Implementation 
Deep Learning Library (DLL) 
https://github.com/wichtounet/dll 
RBM 
Binary, Gaussian, Softmax, ReLU units 
CD and PCD 
Momentum, Weight Decay, Sparsity Target 
Convolutional RBM 
Standard version 
Probabilistic Max Pooling 
Various units 
CD and PCD 
Momentum, Weight Decay, Sparsity Target 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
Deep Learning 
Restricted Boltzmann Machine 
Deep Belief Network 
Convolutional RBM 
Convolutional DBN 
Conclusion 
Implementation 
Conclusion 
Implementation 
DBN 
Pretraining with RBM 
Fine-tuning with Conjugate Gradient 
Fine-tuning with Stochastic Gradient Descent 
Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning

Deep learning presentation

  • 1.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Deep Learning Baptiste Wicht baptiste.wicht@gmail.com September 12, 2014 Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 2.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Table of Contents 1 Deep Learning 2 Restricted Boltzmann Machine 3 Deep Belief Network 4 Convolutional RBM 5 Convolutional DBN 6 Conclusion Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 3.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition History Usages Difficulties Contents 1 Deep Learning Definition History Usages Difficulties 2 Restricted Boltzmann Machine 3 Deep Belief Network 4 Convolutional RBM 5 Convolutional DBN 6 Conclusion Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 4.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition History Usages Difficulties Definition Deep Learning (Wikipedia) Deep learning is a set of algorithms in machine learning that attempt to model high-level abstractions in data by using model architectures composed of multiple non-linear transformations Deep Learning (deeplearning.net) Deep Learning is a new area of Machine Learning research, which has been introduced with the objective of moving Machine Learning closer to one of its original goals: Artificial Intelligence. Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 5.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition History Usages Difficulties Definition (cont.d) Goal: Imitate the nature Set of algorithms Generally structures with multiple layers Often unsupervised feature learning Time-consuming training Sometimes large amount of data Generally complex data New name for an old thing hot topic Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 6.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition History Usages Difficulties History 1960: Neural networks 1985: Multilayer Perceptrons 1986: Restricted Boltzmann Machine 1995: Support Vector Machine 2006: Hinton presents the Deep Belief Network (DBN) New interests in deep learning and RBM State of the art MNIST 2009: Deep Recurrent Neural Network 2010: Convolutional DBN 2011: Max-Pooling CDBN Many competitions won and state of the art results Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 7.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition History Usages Difficulties Names Geoffrey Hinton Andrew Y. Ng Yoshua Bengio Honglak Lee Yann LeCun ... Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 8.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition History Usages Difficulties Algorithms Deep Neural Networks Deep Belief Networks Convolutional Deep Belief Networks Deep SVM Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 9.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition History Usages Difficulties Usages Text recognition Facial Expression Recognition Object Recognition Audio classification Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 10.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition History Usages Difficulties Difficulties Large number of free variables Few insights on how to set them Complex to implement Large variations between papers Lot of refinements were proposed Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 11.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Contents 1 Deep Learning 2 Restricted Boltzmann Machine Definition Training Units Variants 3 Deep Belief Network 4 Convolutional RBM 5 Convolutional DBN 6 Conclusion Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 12.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Definition Restricted Boltzmann Machine Function: Learn a probability distribution over the input Generative stochastic neural network Visible and hidden neurons Neurons form a bipartite graph V visible units and visible biases H hidden units and hidden biases VxH weights Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 13.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Definition (Cont.d) Binary units (Bernoulli RBM) p(hj = 1|v) = (cj + mX i viwi,j ) p(vi = 1|h) = (bi + nX j hjwi,j ) Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 14.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Example Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 15.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Example Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 16.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Example Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 17.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Example Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 18.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Example Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 19.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Usages Unsupervised feature learning Classification with other techniques (linear classifier, SVM, ...) Limited to one layer of abstraction Stacking for higher-level models and classification Deep Belief Network Deep Boltzmann Machines Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 20.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Training Objective: Maximizing the log-likelihood Intractable Other methods have been developed: Markov Chain Monte Carlo (MCMC) (Too slow) Contrastive Divergence (CD) (Hinton) Persistent CD Mean-Field CD (mf-CD) Parallel Tempering Annealed Importance Sampling Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 21.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Contrastive Divergence For each data point 1 Compute gradients g between t = k and t = k − 1 2 Add g to the weights and the biases Repeat for several epochs Experiments have shown that CD1 (k = 1) works well Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 22.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Contrastive Divergence When to stop training ? 1 Proxies to log-likelihood: Reconstruction error Pseudo-likelihood (PCD) 2 Visual inspection of the filters Training is relatively fast Can be trained on GPU Hard to compare two RBMs Hard to test an implementation correctly Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 23.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Contrastive Divergence Options Mini-batch training Momentum Weight decay Sparsity Target ... Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 24.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Units RBM Was initially developed with binary units Different types of units can be used: Gaussian visible units for real-value inputs Softmax hidden unit for classification (last layer) Rectified Linear Unit (ReLU) units for hidden/visible Can be capped Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 25.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Units Variants Variants Convolutional RBM (see later) mean-covariance RBM (mcRBM) Sparse RBM (SRBM) Third-Order RBM Spike And Slab RBM Nonnegative RBM ... Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 26.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Contents 1 Deep Learning 2 Restricted Boltzmann Machine 3 Deep Belief Network Definition Training 4 Convolutional RBM 5 Convolutional DBN 6 Conclusion Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 27.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Definition Deep Belief Network Generative graphical model Type of Deep Neural Network Multiple layer of hidden units Stack of RBMs Can be implemented with other autoencoders Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 28.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Definition (Cont.d) Each RBM takes input from previous layer output Each layer forms a higher-level representation of the data Number of hidden units in each layer can be tuned Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 29.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Training 1 Train each layer, from bottom to top, with Contrastive Divergence (Unsupervised) 2 Then treat the DBN as a MLP 3 If necessary, fine-tune the last layer for classification (Supervised) Back propagation nonlinear Conjugate Gradient method Limited Memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) Hessian-Free CG (Martens) Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 30.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Probabilistic Max Pooling Contents 1 Deep Learning 2 Restricted Boltzmann Machine 3 Deep Belief Network 4 Convolutional RBM Definition Training Probabilistic Max Pooling 5 Convolutional DBN 6 Conclusion Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 31.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Probabilistic Max Pooling Definition Convolutional RBM Motivation: Translation-invariance Scaling to full-size images Variant of RBM, concepts remain the same NV xNV binary visible units K groups of hidden units NKxNK binary hidden units per group Each group has a NWxNW filter (NW , NV − NH + 1) A bias bk for each hidden group A single bias c for all visible units Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 32.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Probabilistic Max Pooling Definition (Cont.d) Binary units: p(hk j = 1|v) = (bk + (W~ k v v)j ) p(vi = 1|h) = (c + KX k (Wk f hk )i) Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 33.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Probabilistic Max Pooling Training Contrastive Divergence Gradients computations are done with convolutions Same refinements can be used (weight decay, momentum, ...) CRBM is highly overcomplete Sparse learning is very important Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 34.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Probabilistic Max Pooling Probabilistic Max Pooling Shrink the representation by a constant factor C Allows higher-level to be invariant to small translations Reduces computational effort Generative version of standard Max Pooling Pooling layer with K groups of pooling units Each group has NPxNP units NP , NH/C Each hidden block (CxC) is connected to exactly one pooling unit Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 35.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Training Probabilistic Max Pooling Definition (Cont.d) Binary units: p(vi = 1|h) = (c + KX k (Wk f hk )i) I(hk j ) , bk + (W~ k v v)j p(hk j = 1|v) = exp(I(hk i )) 1 + P j02
  • 36.
    exp(I(hk i0)) p(pk = 0|v) = 1 1 + P j02
  • 37.
    exp(I(hk i0)) BaptisteWichtbaptiste.wicht@gmail.com Deep Learning
  • 38.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Contents 1 Deep Learning 2 Restricted Boltzmann Machine 3 Deep Belief Network 4 Convolutional RBM 5 Convolutional DBN 6 Conclusion Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 39.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Definition Stack of Convolutional RBM With or without Probabilistic Max Pooling Each RBM takes input from previous layer output Each layer forms a higher-level representation of the data Number of hidden units in each layer can be tuned Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 40.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Feature Learning Source: Honglak Lee Each layer learns a different abstraction of features 1 Stroke 2 Parts of faces 3 Faces Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 41.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Implementation Conclusion Contents 1 Deep Learning 2 Restricted Boltzmann Machine 3 Deep Belief Network 4 Convolutional RBM 5 Convolutional DBN 6 Conclusion Implementation Conclusion Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 42.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Implementation Conclusion Implementation Deep Learning Library (DLL) https://github.com/wichtounet/dll RBM Binary, Gaussian, Softmax, ReLU units CD and PCD Momentum, Weight Decay, Sparsity Target Convolutional RBM Standard version Probabilistic Max Pooling Various units CD and PCD Momentum, Weight Decay, Sparsity Target Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning
  • 43.
    Deep Learning RestrictedBoltzmann Machine Deep Belief Network Convolutional RBM Convolutional DBN Conclusion Implementation Conclusion Implementation DBN Pretraining with RBM Fine-tuning with Conjugate Gradient Fine-tuning with Stochastic Gradient Descent Baptiste Wichtbaptiste.wicht@gmail.com Deep Learning