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A comment on A tutorial on the free-energy framework for modelling perception and learning.

Re:A tutorial on the free-energy framework for modelling per... by tomjakubowski on Friday July 06, 2018 @08:44PM (#17476196)
> The non-linear function that relates size v to photosensory input u is assumed to be g(v)=v^2

I am having a hard time understanding this sentence - how does g(v) = v^2 relate the size v and the input u if the expression mentions only v?

Is it meant to be v = g(u) = u^2? Is it u = g(v) = v^2?

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Re:A tutorial on the free-energy framework for modelling per... by yorwba on Friday July 06, 2018 @09:11PM (#17476277)
"We assume that this signal [i.e. u] is normally distributed with mean g(v) and variance Σ_v."

That means that there's no deterministic function that fixes u for a given v, but only a distribution of possible values. (It's closer to u = v^2 than the opposite, though.) The precise relationship is expressed symbolically in the likelihood function given in the next part.

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Re:A tutorial on the free-energy framework for modelling per... by tomjakubowski on Friday July 06, 2018 @09:27PM (#17476327)
Thank you!
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