Deep Learning - A Literature survey
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Transcript of Deep Learning - A Literature survey
A Technical seminar on
“DEEP LEARNING”
Student: Akshay N. Hegde 1RV12SIT02 Mtech –IT 1st sem
Department of ISE, RVCE
Presentation Outline• INTRODUCTION• LITERATURE SURVEY• EXAMPLES• METHADOLOGY• EXPERIMENTS• RESULTS• CONCLUSION AND FUTURE WORK• REFERENCES
INTRODUCTION• What is Deep Learning?• Some successful stories.• Examples of Deep learning.• Learning and training of Objects.• Conclusion & Future scope
Dept. of ISE, RVCE.
What is Deep learning?
• “Automatically learning multiple levels of representations of the underlying distribution of the data to be modelled”
• Deep learning algorithms have shown superior learning and classification performance
• In areas such as transfer learning, speech and handwritten character recognition, face recognition among others.
• A deep learning algorithm automatically extracts the low & high-level features necessary for classification.
• By high level features, one means feature that hierarchically depends on other features.
• “Automatic representation learning” is key point of interest of this kind of approach as the need for potentially time consuming handcrafted feature design is eliminated.
Semi-supervised learning
Unlabeled images (all cars/motorcycles)
What is this?
Car Motorcycle
Hierarchies in Vision• Lampert et al. CVPR’09
• Learn attributes, then classesas combination of attributes
ClassLabels
Attributes
Image Features
What we can do ? (With the right dataset)
• Recognize faces
• Categorize scenes
• Detect, segment and track objects
• 3D from multiple images or stereo
• Classify actions
What we can do..
Detect and Localize ObjectsCategorize Scenes
BEACH
Face Detection and Recognition
Why Deep Learning ?
• Data mining: using historical data to improve decision– medical records ⇒ medical knowledge– log data to model user
• Software applications we can’t program by hand– autonomous driving– speech recognition
• Self customizing programs– Newsreader that learns user interests
Some success stories
• Data Mining
• Analysis of astronomical data• Human Speech Recognition• Handwriting recognition• Face recognition
• Fraudulent Use of Credit Cards• Drive Autonomous Vehicles
• Predict Stock Rates
• Intelligent Elevator Control• DNA Classification
Spectrogram
Detection units
Max pooling unit
Deep learning examplesConvolutional DBN for audio
Convolutional DBN for audio
Spectrogram
Probabilistic max pooling
X3X1 X2 X4
max {x1, x2, x3, x4}
Convolutional Neural net:Convolutional DBN:
X3X1 X2 X4
max {x1, x2, x3, x4}
Where xi are real numbers.
Where xi are {0,1}, and mutually exclusive. Thus, 5 possible cases:
Collapse 2n configurations into n+1 configurations. Permits bottom up and top down inference.
0
0 0 0 0
0
0 0 0 0 0 0 0 0 0 0
00000 0
1 1
1
1
11
1
1
Convolutional DBN for audio
One CDBN layerDetection units
Max pooling
Detection units
Max poolingSecond CDBN
layer
Convolutional DBN for Images
Visible nodes (binary or real)
Wk
Detection layer H
Max-pooling layer P
Hidden nodes (binary)
“Filter” weights (shared)
‘’max-pooling’’ node (binary)
Input data V
Convolutional DBN on face images
pixels
edges
object parts(combination of edges)
object models
Learning of object parts
Examples of learned object parts from object categoriesFaces Cars Elephants Chairs
Training on multiple objects
Plot of H(class|neuron active)
Trained on 4 classes (cars, faces, motorbikes, airplanes).
Second layer: Shared-features and object-specific features.
Third layer: More specific features.
• Unsupervised feature learning: Does it work?
Unsupervised & Supervised Training
EXPERIMENTS & RESULTS
State-of-the-art task performance
TIMIT Phone classification Accuracy
Prior art (Clarkson et al.,1999) 79.6%
Stanford Feature learning 80.3%
TIMIT Speaker identification Accuracy
Prior art (Reynolds, 1995) 99.7%Stanford Feature learning 100.0%
Audio
Images
Multimodal (audio/video)
CIFAR Object classification Accuracy
Prior art (Yu and Zhang, 2010) 74.5%
Stanford Feature learning 75.5%
NORB Object classification Accuracy
Prior art (Ranzato et al., 2009) 94.4%
Stanford Feature learning 96.2%
AVLetters Lip reading Accuracy
Prior art (Zhao et al., 2009) 58.9%Stanford Feature learning 63.1%
VideoUCF activity classification Accuracy
Prior art (Kalser et al., 2008) 86%
Stanford Feature learning 87%
Hollywood2 classification Accuracy
Prior art (Laptev, 2004) 47%Stanford Feature learning 50%
• Fig. 1. DeSTIN Hierarchy for the MNIST dataset studies. Four layers are used with 64, 16, 4 and 1 node per layer arranged in a hierarchical manner.
• At each node the output belief b(s) at each temporal step is fed to a parent-node.
• At each temporal step the parent receives input beliefs from four
child nodes to generate its own belief (fed to its parent) and an advice value a which is fed back to the child nodes.
Named-entity recognition (NER)
• Also known as entity identification and entity extraction is a subtask of information extraction that seeks to locate and classify atomic elements in text into predefined categories such as the names of persons, organizations, locations, expressions of times, quantities, monetary values, percentages, etc.
• Most research on NER systems has been structured as taking an unannotated block of text, such as this one:
• “Jim bought 300 shares of Acme Corp. in 2006.”
• And producing an annotated block of text, such as this one:
<ENAMEX TYPE="PERSON"> Jim </ENAMEX> bought <NUMEX TYPE="QUANTITY"> 300 </NUMEX> shares of <ENAMEX TYPE="ORGANIZATION"> Acme Corp. </ENAMEX> in <TIMEX TYPE="DATE">2006</TIMEX>
• State-of-the-art NER systems for English produce near-human performance. For example, the best system entering MUC-7 scored 93.39% of F measure while human annotators scored 97.60% and 96.95%
CONCLUSION & FUTURE WORK
• Test result shows that a deep learning approach allows better classification than popular classifiers on the handcrafted features chosen in this work.
• This is a significant advantage over the typical classification approach that requires careful (and possibly time consuming) selection of features.
• Instead of hand-tuning features, use unsupervised feature learning
• Advanced topics:o Self-taught learning o Scaling up
• More practical implementations must be done.• Researches are going on by Stanford University.
REFERENCES• [1]D. Erhan, Y. Bengio, A. Courville, P. A. Manzagol, P. Vincent, and S. Bengio, "Why Does
Unsupervised Pre-training Help Deep Learning?," Journal of Machine Learning Research, vol. 11, pp. 625-660, Feb 2010.
• [2] P. Vincent, H. Larochelle, I. Lajoie, Y. Bengio, and P.-A. Manzagol, "Stacked Denoising Autoencoders: Learning Useful Representations in a Deep Network with a Local Denoising Criterion," Journal of Machine Learning Research, vol. 11, 2010.
• [3] G. Hinton, S. Osindero, and Y. Teh, “A fast learning algorithm for deep belief nets,” Neural computation, vol. 18, no. 7, pp. 1527–1554, 2006.
• [4] D. Keysers, “Comparison and Combination of State-of-the-art Techniques for Handwritten Character Recognition: Topping the MNIST Benchmark,” Arxiv preprint arXiv:0710.2231, 2007.
• [5] H. Lee, Y. Largman, P. Pham, and A. Ng, “Unsupervised feature learning for audio classification using convolutional deep belief networks,”Advances in neural information processing systems, vol. 22, pp. 1096– 1104, 2009.
• [6] Francis, Quintal, Lauzon, “An introduction to deep learning,” IEEE Transactions on Deep Learning, pp. 1438–1439, 2012.