吴恩达《深度学习》-课后测验-第一门课 (Neural Networks and Deep Learning)-Week 4 - Key concepts on Deep Neural Networks（第四周 测验 – 深层神经网络）

Week 4 Quiz - Key concepts on Deep Neural Networks（第四周 测验 – 深层神经网络）

\1. What is the “cache” used for in our implementation of forward propagation and backward propagation?(在实现前向传播和反向传播中使用的“cache”是什么？)

【 】It is used to cache the intermediate values of the cost function during training.(用于在训练期间缓存成本函数的中间值。)

【 】We use it to pass variables computed during forward propagation to the corresponding backward propagation step. It contains useful values for backward propagation to compute derivatives.(我们用它传递前向传播中计算的变量到相应的反向传播步骤，它包含用于计算导数的反向传播的有用值。)

【 】It is used to keep track of the hyperparameters that we are searching over, to speed up computation.(它用于跟踪我们正在搜索的超参数，以加速计算。)

【 】We use it to pass variables computed during backward propagation to the corresponding forward propagation step. It contains useful values for forward propagation to compute activations.(我们使用它将向后传播计算的变量传递给相应的正向传播步骤，它包含用于计算计算激活的正向传播的有用值。)

答案

【★】We use it to pass variables computed during forward propagation to the corresponding backward propagation step. It contains useful values for backward propagation to compute derivatives.(我们用它传递前向传播中计算的变量到相应的反向传播步骤，它包含用于计算导数的反向传播的有用值。)

Note: the “cache” records values from the forward propagation units and sends it to the backward propagation units because it is needed to compute the chain rule derivatives.(请注意：“cache”记录来自正向传播单元的值并将其发送到反向传播单元，因为需要链式计算导数。)

 

\2. Among the following, which ones are “hyperparameters”? (Check all that apply.)(以下哪些是“超参数”？)

【 】size of the hidden layers \(