d PR-∞∞g(χ)g ⅛j + χ) Q g (⅛Wk + x>
dri(wi)
dwi
- μ-j=--------7------kj-7------<0- < 0. (54)
μw PR-∞∞ h (x) h (pj-pi + x) Q H (pk-pi + x)dx
j≠i 4 M k k≠i,j ^ 7
Note that, at the symmetric equilibrium:
dPw (n 1) ∞
---- =------- I g (x) G (x) dx,i = 1...n. (55)
dWi ISym μw ./ ∞ ,
Therefore:
dri(wi) μd Γw
(56)
------ =---T
dwi |Sym μw γ-
where Γw = R-∞∞ g2 (x) Gn-2 (x) dx and Γ- = R-∞∞ h2 (x) Hn-2 (x) dx. The
profit function is now:
πei (wi ,w-i ,p)= [ri (wi) - wi - c] NPiw - (F + S) . (57)
B.2 Short-run equilibrium
The best reply of subcenter i is (seeing w.l.o.g. N =1)
dei(wi,w-i,P) _ d dri (wi) Λ P w ( ( } ʌ dPw
dWi =V dWi - 1) Pi + (ri (wi) - wi - c) dWi .
Thus, using (55) and (55) we get:
- μ~ rw + 1^ 1 + (pe - We - c) (n - 1) Γw = 0 (58)
Vw Γ- J n p μw v 7
Or:
i i 1 μ-d μw∖
pe = c+we+ nτn-!) Vr-+ H.
Note that, for the double exponential distribution Γd = Γw =1 n2 , then
we get the formula: (17), as expected. We have therefore proved the following
result:
Proposition 8 Consider a differentiated labour and product labour. with i.i.d.
preferences with density function h (.) for the product market and g (.) for the
labour market Then, there exists a unique symmetric Nash equilibrium in prices
and wages given by:
pe = c + We +
1
n(n- 1)
μ________μ-__.__μw________ʌ
\ R-∞∞ h2 (x) H n-2 (x) dx R∞∞ 92 (x) Gn-2 (x) dx J
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