课程二(Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization)，第二周（Optimization algorithms） —— 2.Programming assignments:Optimization

Optimization Welcome to the optimization's programming assignment of the hyper-parameters tuning specialization. There are many different optimization algorithms you could be using to get you to the minimal cost. Similarly, there are many different p…

课程二(Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization)，第三周（Hyperparameter tuning, Batch Normalization and Programming Frameworks） —— 2.Programming assignments

Tensorflow Welcome to the Tensorflow Tutorial! In this notebook you will learn all the basics of Tensorflow. You will implement useful functions and draw the parallel with what you did using Numpy. You will understand what Tensors and operations are,…

课程二(Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization)，第一周（Practical aspects of Deep Learning） —— 4.Programming assignments:Gradient Checking

Gradient Checking Welcome to this week's third programming assignment! You will be implementing gradient checking to make sure that your backpropagation implementation is correct. By completing this assignment you will: - Implement gradient checking…

课程回顾-Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization

训练.验证.测试划分的量要保证数据来自一个分布偏差方差分析如果存在high bias如果存在high variance正则化正则化减少过拟合的intuitionDropoutdropout分析其它正则化方法数据增加(data augmentation)early stoppingensemble归一化输入归一化可以加速训练归一化的步骤归一化应该应用于:训练.验证.测试梯度消失/爆炸权重初始化通过数值近似计算梯度优化算法mini-batchmomentumRMSpropAdam调参顺序批规范化Ba…

《Improving Deep Neural Networks:Hyperparameter tuning, Regularization and Optimization》课堂笔记

Lesson 2 Improving Deep Neural Networks:Hyperparameter tuning, Regularization and Optimization 这篇文章其实是 Coursera 上吴恩达老师的深度学习专业课程的第二门课程的课程笔记. 参考了其他人的笔记继续归纳的. 训练,验证,测试集 (Train / Dev / Test sets) 在机器学习发展的小数据量时代,常见做法是将所有数据三七分,就是人们常说的 70% 训练集,30% 测试集.如果明确设…

Coursera Deep Learning 2 Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization - week1, Assignment(Initialization)

声明:所有内容来自coursera,作为个人学习笔记记录在这里. Initialization Welcome to the first assignment of "Improving Deep Neural Networks". Training your neural network requires specifying an initial value of the weights. A well chosen initialization method will help…

[C4] Andrew Ng - Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization

About this Course This course will teach you the "magic" of getting deep learning to work well. Rather than the deep learning process being a black box, you will understand what drives performance, and be able to more systematically get good res…

Coursera Deep Learning 2 Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization - week2, Assignment(Optimization Methods)

声明:所有内容来自coursera,作为个人学习笔记记录在这里. 请不要ctrl+c/ctrl+v作业. Optimization Methods Until now, you've always used Gradient Descent to update the parameters and minimize the cost. In this notebook, you will learn more advanced optimization methods that can spee…

Coursera, Deep Learning 2, Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization - week1, Course

Train/Dev/Test set Bias/Variance Regularization 有下面一些regularization的方法. L2 regularation drop out data augmentation(翻转图片得到一个新的example), early stopping(画出J_train 和J_dev 对应于iteration的图像) L2 regularization: Forbenius Norm. 上面这张图提到了weight decay 的概念 Weigh…

Coursera Deep Learning 2 Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization - week1, Assignment(Gradient Checking)

声明:所有内容来自coursera,作为个人学习笔记记录在这里. Gradient Checking Welcome to the final assignment for this week! In this assignment you will learn to implement and use gradient checking. You are part of a team working to make mobile payments available globally, and…

吴恩达《深度学习》-第二门课 (Improving Deep Neural Networks:Hyperparameter tuning, Regularization and Optimization)-第一周：深度学习的实践层面 (Practical aspects of Deep Learning) -课程笔记

第一周:深度学习的实践层面 (Practical aspects of Deep Learning) 1.1 训练,验证,测试集(Train / Dev / Test sets) 创建新应用的过程中,不可能从一开始就准确预测出一些信息和其他超级参数,例如:神经网络分多少层:每层含有多少个隐藏单元:学习速率是多少:各层采用哪些激活函数.应用型机器学习是一个高度迭代的过程. 从一个领域或者应用领域得来的直觉经验,通常无法转移到其他应用领域,最佳决策取决于所拥有的数据量,计算机配置中输入特征的数量,…

Coursera Deep Learning 2 Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization - week3, Hyperparameter tuning, Batch Normalization and Programming Frameworks

Tuning process 下图中的需要tune的parameter的先后顺序, 红色>黄色>紫色,其他基本不会tune. 先讲到怎么选hyperparameter, 需要随机选取(sampling at random) 随机选取的过程中,可以采用从粗到细的方法逐步确定参数有些参数可以按照线性随机选取, 比如 n[l] 但是有些参数就不适合线性的sampling at radom, 比如 learning rate α,这时可以用 log Andrew 很幽默的讲到了两种选参数的实际场景…

Coursera Deep Learning 2 Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization - week1, Assignment(Regularization)

声明:所有内容来自coursera,作为个人学习笔记记录在这里. Regularization Welcome to the second assignment of this week. Deep Learning models have so much flexibility and capacity that overfitting can be a serious problem, if the training dataset is not big enough. Sure it do…

吴恩达《深度学习》-课后测验-第二门课 (Improving Deep Neural Networks:Hyperparameter tuning, Regularization and Optimization)-Week 1 - Practical aspects of deep learning（第一周测验 - 深度学习的实践）

Week 1 Quiz - Practical aspects of deep learning(第一周测验 - 深度学习的实践) \1. If you have 10,000,000 examples, how would you split the train/dev/test set? (如果你有 10,000,000 个样本,你会如何划分训练/开发/测试集?) [ ]98% train . 1% dev . 1% test(训练集占 98% , 开发集占 1% , 测试集占 1%) 答案…

Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization（第一周）深度学习的实践层面 (Practical aspects of Deep Learning)

1. Setting up your Machine Learning Application 1.1 训练,验证,测试集(Train / Dev / Test sets) 1.2 Bias/Variance(偏差和方差) 高偏差(high bias)称为"欠拟合"(underfitting), 练集误差与验证集误差都高. 高方差(high variance)称为过拟合(overfitting), 训练集误差很低而验证集误差很高. 1.3 Basic "recipe"…

Coursera Deep Learning 2 Improving Deep Neural Networks: Hyperparameter tuning, Regularization and Optimization - week2, Optimization algorithms

Gradient descent Batch Gradient Decent, Mini-batch gradient descent, Stochastic gradient descent 还有很多比gradient decent 更优化的算法,在了解这些算法前,需要先理解 Exponentially weighted averages 这个概念 Exponentially weighted average 是一种计算平均值的方法,非常省storage 和 memory, 但是不是很精确.…

[C2W3] Improving Deep Neural Networks : Hyperparameter tuning, Batch Normalization and Programming Frameworks

第三周:Hyperparameter tuning, Batch Normalization and Programming Frameworks 调试处理(Tuning process) 目前为止,你已经了解到,神经网络的改变会涉及到许多不同超参数的设置.现在,对于超参数而言,你要如何找到一套好的设定呢?在本节中,我想和你分享一些指导原则,一些关于如何系统地组织超参调试过程的技巧,希望这些能够让你更有效的聚焦到合适的超参设定中. 关于训练深度神经网络最难的事情之一是你要处理的参数的数量,下面粗…

Improving Deep Neural Networks 笔记

1 Practical aspects of Deep Learning 1.1 Train/Dev/Test sets 在小样本的机器学习中,可以分为60/20/20. 在大数据训练中,不需要划分很多的开发集和测试集.假如共有一百万数据,可以只取其中1万条作为开发集,1万条作为测试集.剩下的作为训练集. 某些时候会没有开发集.但是这么叫不确切,应该成为没有测试机. 注意:这里的train/dev/test应该是同一个数据集里.例如图片什么的需要相同的分辨率. 1.2 bias/variance…

[C2W2] Improving Deep Neural Networks : Optimization algorithms

第二周:优化算法(Optimization algorithms) Mini-batch 梯度下降(Mini-batch gradient descent) 本周将学习优化算法,这能让你的神经网络运行得更快.机器学习的应用是一个高度依赖经验的过程,伴随着大量迭代的过程,你需要训练诸多模型,才能找到合适的那一个,所以,优化算法能够帮助你快速训练模型. 我们希望可以利用一个巨大的数据集来训练神经网络,而深度学习没有在大数据领域发挥最大的效果其中一个难点在于,在巨大的数据集基础上进行训练速度很慢.因此…

[C2W1] Improving Deep Neural Networks : Practical aspects of Deep Learning

第一周:深度学习的实用层面(Practical aspects of Deep Learning) 训练,验证,测试集(Train / Dev / Test sets) 本周,我们将继续学习如何有效运作神经网络,内容涉及超参数调优,如何构建数据,以及如何确保优化算法快速运行,从而使学习算法在合理时间内完成自我学习.第一周,我们首先说说神经网络机器学习中的问题,然后是随机失活神经网络,还会学习一些确保神经网络正确运行的技巧,带着这些问题,我们开始今天的课程. 在配置训练.验证和测试数据集的过程中做…

课程一(Neural Networks and Deep Learning)，第四周（Deep Neural Networks） —— 3.Programming Assignments: Deep Neural Network - Application

Deep Neural Network - Application Congratulations! Welcome to the fourth programming exercise of the deep learning specialization. You will now use everything you have learned to build a deep neural network that classifies cat vs. non-cat images. In…

Neural Networks and Deep Learning 课程笔记（第四周）深层神经网络（Deep Neural Networks）

1. 深层神经网络(Deep L-layer neural network ) 2. 前向传播和反向传播(Forward and backward propagation) 3. 总结 4. 深层网络中的前向传播(Forward propagation in a Deep Network) 向量化实现过程可以写成: 注:这里只能用一个显示for循环,l 从 1 到 L,然后一层接着一层去计算. 如何减少bug 4.1 核对矩阵的维数(Getting your matrix dimensions…

吴恩达《深度学习》-第一门课 (Neural Networks and Deep Learning)-第四周：深层神经网络(Deep Neural Networks)-课程笔记

第四周:深层神经网络(Deep Neural Networks) 4.1 深层神经网络(Deep L-layer neural network) 有一些函数,只有非常深的神经网络能学会,而更浅的模型则办不到. 对于给定的问题很难去提前预测到底需要多深的神经网络,所以先去尝试逻辑回归,尝试一层然后两层隐含层, 然后把隐含层的数量看做是另一个可以自由选择大小的超参数,然后再保留交叉验证数据上评估,或者用开发集来评估. 一些符号注意: 用 L 表示层数,上图5hidden layers :…

Must Know Tips/Tricks in Deep Neural Networks

Must Know Tips/Tricks in Deep Neural Networks (by Xiu-Shen Wei) Deep Neural Networks, especially Convolutional Neural Networks (CNN), allows computational models that are composed of multiple processing layers to learn representations of data with…

Must Know Tips/Tricks in Deep Neural Networks (by Xiu-Shen Wei)

http://lamda.nju.edu.cn/weixs/project/CNNTricks/CNNTricks.html Deep Neural Networks, especially Convolutional Neural Networks (CNN), allows computational models that are composed of multiple processing layers to learn representations of data with mul…

[C1W4] Neural Networks and Deep Learning - Deep Neural Networks

第四周:深层神经网络(Deep Neural Networks) 深层神经网络(Deep L-layer neural network) 目前为止我们学习了只有一个单独隐藏层的神经网络的正向传播和反向传播,还有逻辑回归,并且你还学到了向量化,这在随机初始化权重时是很重要.本周所要做的是把这些理念集合起来,就可以执行你自己的深度神经网络. 严格上来说逻辑回归也是一个一层的神经网络,浅与深仅仅是指一种程度.有一个隐藏层的神经网络,就是一个两层神经网络.当我们算神经网络的层数时,我们不算输入层,我们只…