mathematical optimization - Why aren't neural networks convex? -


unlike linear , logistic regression, anns cost functions not convex, , susceptible local optima. can provide intuition why case anns , why hypothesis cannot modified produce convex function?

i found sufficient explanation here:

https://stats.stackexchange.com/questions/106334/cost-function-of-neural-network-is-non-convex

basically since weights permutable across layers there multiple solutions minima achieve same results, , function cannot convex (or concave either).


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