In[]:=
Clear["Global`*"]​​​​B:=.1​​ϵ:=3​​β:=.3​​σ:=1​​alphabar:=0.​​s:=1​​u:=.3​​ϕ[Z_]:=PDF[NormalDistribution[0,1],Z]​​Φ[Z_]:=CDF[NormalDistribution[0,1],Z]​​IMR[Z_]:=ϕ[Z]/Φ[Z]​​​​g[z_,n_]:=(s-u)*(σ*z+alphabar)+Log[n]+
Log
IMR[σ*s-z]
IMR[z-σ*u]

(ϵ-1)*(1-β)
​​​​h[n_]:=z/.FindRoot[g[z,n],{z,0}]​​Plot[h[n],{n,.01,100}]​​
Out[]=
20
40
60
80
100
-1.6
-1.4
-1.2
-1.0
-0.8
-0.6
-0.4
-0.2
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