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thanks to Ulrich Neumann I am getting close to the solution of my problem... However, Mathematica tells me that no points satisfy the constraints of the following problem:

 i = 117; A = 1*10^4; a = 10;
f[w_?NumericQ, p_?NumericQ] := (A - a p) (p - w) 
pR[w_?NumericQ] := Block[{p}, NArgMax[{f[w, p], p >= 0, w >= i}, p]]
J[w_?NumericQ] := (A - a pR[w]) (w - i)
NMaximize[{J[w], {w > i, f[w, pR[w]] > 0}}, w, Method -> "NelderMead",
  AccuracyGoal -> 3]

Yet, it is easy to show that $pR[181]=590.5$ and $f[181, 590]>0$, so that $w>i$, $p>=0$ and $f[w, pR[w]] > 0$ are fulfilled.

So where exactly is this code letting me down?

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1 Answer 1

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Remove the constraint w>i. NArgMax expects only constraints depending on p!

pR[w_?NumericQ] :=Block[{p}, NArgMax[{f[w, p], p >= 0(*,w\[GreaterEqual]i*)}, p]]

Now the NMaximize evaluates

J[w_?NumericQ] := (A - a pR[w]) (w - i)
NMaximize[{J[w], {w > i, f[w, pR[w]] > 0}}, w,Method ->"NelderMead",AccuracyGoal -> 3, EvaluationMonitor :> Print[{w, J[w]}]]

but probably didn't find a solution...

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