如何识别神经网络的神经元与层数？请求验证谷歌图片猜测

Hey there! Let's clear up the confusion around counting neurons and layers in neural networks—it's a super common sticking point when you're starting out.

First, Let's Lock Down the Definitions #

There are two key conventions to keep in mind, since different resources might use slightly different rules:

• Neurons: Every single node/circle in the diagram counts as a neuron. That includes input neurons (the leftmost row), hidden neurons (middle rows), and output neurons (rightmost row). No exceptions here—just count all the circles!
• Layers: This is where things can vary:
  • Standard deep learning convention: We only count computational layers (hidden layers + output layer). The input layer doesn't get counted because it doesn't perform any computation—it just passes data into the network.
  • Some introductory resources: They might include the input layer when counting total layers. So you'll see phrases like "3-layer network" referring to input + 1 hidden + output.

Relating This to Your Lecture Slide #

Your slide says 3 neurons and 2 layers. Using the standard convention, that means you've got 2 computational layers (hidden + output) with a total of 3 neurons split between them—like 2 hidden neurons + 1 output neuron, or 1 hidden + 2 output. If the slide was using the inclusive convention, it would be input + 1 hidden layer (but that would be 2 layers total, with 3 neurons across both—so input might have 1, hidden 2, for example).

Verifying Your Google Image Guess #

Since I can't see the image you found, if you can describe its structure (e.g., "3 rows of neurons: left row has 4, middle has 5, right has 2"), I can confirm your count right away. For example:

• If your guess was "8 neurons, 2 layers" for an image with 3 input, 3 hidden, 2 output: That's correct! Total neurons = 3+3+2=8, and 2 computational layers (hidden + output).
• If you guessed "3 layers" for that same image: That's only correct if the resource counts the input layer as a layer.

Fire away with the image details, and we'll get your guess verified!

内容的提问来源于stack exchange，提问作者asilvester635