# Identify What Does Not Fix Vanishing Gradients
Which change is not a reliable remedy for vanishing gradients in a deep neural network: adding skip connections, using an activation such as ReLU, raising the learning rate, or adding batch normalization? Explain the mechanism behind your choice and the limitations of the other interventions.
### What a Strong Answer Covers
- Gradient propagation through a product of layer derivatives.
- Why increasing the optimizer step size does not repair a vanishing gradient signal.
- How skip connections, activation choice, and normalization can help without guaranteeing a cure.
```hint Separate signal from step size
The gradient is computed before the optimizer multiplies it by the learning rate.
```
### Follow-up Questions
- Can ReLU units still stop transmitting gradients?
- Why can residual connections help very deep models?
Overview: Explain why raising the learning rate does not fix vanishing gradients and compare skip connections, ReLU, and batch normalization.
Which change is not a reliable remedy for vanishing gradients in a deep neural network: adding skip connections, using an activation such as ReLU, raising the learning rate, or adding batch normalization? Explain the mechanism behind your choice and the limitations of the other interventions.
What a Strong Answer Covers Guidance
Gradient propagation through a product of layer derivatives.
Why increasing the optimizer step size does not repair a vanishing gradient signal.
How skip connections, activation choice, and normalization can help without guaranteeing a cure.
Follow-up Questions Guidance
Can ReLU units still stop transmitting gradients?
Why can residual connections help very deep models?