Coursera 深度学习笔记 I.Neural Networks and Deep learning-01介绍
01. Introduction to Deep learning
1. What is a neural network
example 1-Single neural network
Housing price prediction
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linear regression problem
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ReLU (Rectified Linear Unit 修正线性单元) function
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A “Neuron” is what connects the input(x=size) with the output(y=price)
example 2-Multiple neural network
- other features besides size, should also be taken into account
- input layer -> hidden unit->y
2. Supervised learning with Neural Networks
supervised learning-> given correct output matching input data
I. regression & classification problems
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regression
- predict results within a continuous output->map input variables to some continuous function
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classification
- discrete output->discrete categories
II. Types of Neural Network
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Concolution Neural Network(CNN)
- images
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Recurrent Neural Network(RNN)
- one-dimentional sequence data
- e.g. translation, speech recognition
- hybrid neural network architecture
- e.g. autonomous driving
III. Structured vs. unstructured data
- Structured data:
- have well-defined features such as price, age
- Unstructured data:
- e.g. pixel, raw audio, text
3. Why is Deep learning taking off
Due to
- a large amount of data available through the digitization of the society
- faster computation
- innovation in the development of neural network algorithm