<p>I've seen several people say that sigmoids are like a saturating firing rate of a neuron but I don't see how or why they interpret it as such. I especially don't see the relationship between a &quot;rate&quot; (so a number of something over time, I guess here it's the number that a neuron activates in a unit of time) and the sigmoid graph. For me it resembles more to the voltage output of an operational amplifier in some cases.</p>

CC BY-SA 4.0
2021-03-21T22:20:27.037Z
Sigmoid outputs a value between 0-1, this can be interpreted as the probability of the neuron ‘firing’.
David
CC BY-SA 4.0
2021-03-21T23:17:18.470Z
@DavidIreland that could be an interpretation. Like the probability of a neuron "firing" when the input is x is $\sigma (x)$ (where $\sigma$ denotes the sigmoid function).
Daviiid
CC BY-SA 4.0
2021-03-22T09:26:40.187Z
It would be nice if you could provide 1-2 references where people say "sigmoids are like a saturating firing rate of a neuron", just to have more context.
nbro
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2021-03-22T11:54:21.700Z
@nbro You're right, sorry for this imprecision. So a friend of mine told me about this interpretation (it was given by his professor and he found it cool) and when I searched for it I found this post: https://datascience.stackexchange.com/questions/14349/difference-of-activation-functions-in-neural-networks-in-general I agree it's not many people I just thought that since it's a professor who said it, he maybe have read/heard it somewhere else etc... ^^'
Daviiid
<artificial-neuron><neurons><sigmoid>
Why is the sigmoid function interpreted as a saturating firing rate of a neuron?
Daviiid
# Why is the sigmoid function interpreted as a saturating firing rate of a neuron?

(Asked by: username_0 on 2021-03-21)

I've seen several people say that sigmoids are like a saturating firing rate of a neuron but I don't see how or why they interpret it as such. I especially don't see the relationship between a "rate" (so a number of something over time, I guess here it's the number that a neuron activates in a unit of time) and the sigmoid graph. For me it resembles more to the voltage output of an operational amplifier in some cases.

**Tags:** artificial-neuron, neurons, sigmoid

> **Comments:**
> **username_1**: Sigmoid outputs a value between 0-1, this can be interpreted as the probability of the neuron ‘firing’.  
> **username_0**: @username_1Ireland that could be an interpretation. Like the probability of a neuron "firing" when the input is x is $\sigma (x)$ (where $\sigma$ denotes the sigmoid function).  
> **username_2**: It would be nice if you could provide 1-2 references where people say "sigmoids are like a saturating firing rate of a neuron", just to have more context.  
> **username_0**: @username_2 You're right, sorry for this imprecision. So a friend of mine told me about this interpretation (it was given by his professor and he found it cool) and when I searched for it I found this post: https://datascience.stackexchange.com/questions/14349/difference-of-activation-functions-in-neural-networks-in-general I agree it's not many people I just thought that since it's a professor who said it, he maybe have read/heard it somewhere else etc... ^^'  

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## 0 answers

