IV - Specific Factors: The Ricardo-Viner Model - Gregory Corcos

in the short run, some factors are mobile across sectors, others not: ... Specific factors model ⇔ short-run. 1 ... Closed economy labor market equilibrium for given.
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IV - Specific Factors: The Ricardo-Viner Model —  How important is the assumption of perfect factor mobility between sectors in the HO model?

—  The specific-factors model takes the polar opposite assumption: some factors are sector-specific

—  Interpretation: factor adjustments take time —  in the short run, some factors are mobile across sectors, others not: capital vs labor, skilled labor vs unskilled —  HO model: all factors are mobile ⇔ long-run Specific factors model ⇔ short-run

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—  Can we still predict the trade content? —  What are the welfare gains? —  Even if the RV setting is close to the HO model, all results will depend on factor mobility or immobility and not on relative endowments

⇒ factor mobility is a critical assumption

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—   1. The Closed Economy —   2 goods, X and Y —   But 3 inputs: labor, L, and 2 types of capital, R and S —  labor is perfectly mobile across sectors —  R and S are specific to sector X and Y, respectively —  Factor endowments: L , R and S

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—  Technology: constant returns to scale

⎧ X = F X (L X , R ) ⎨ ⎩Y = FY (LY , S )

subject to

⎧L X + LY ≤ L ⎪ ⎨R ≤ R ⎪S ≤ S ⎩

—   Competitive equilibrium

⎧ p ∂F X = w ⎪ X ∂L X ⎨ ∂F ⎪ p Y Y = w ⎩ ∂LY

⎧ p ∂F X = r ⎪ X ∂R ⎨ ∂F ⎪ p Y Y = s ⎩ ∂S

! ## R = R " S=S # #$ LX + LY = L

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—  Recall: decreasing marginal productivities

∂F X (LX , R ) ∂L X − +

∂F X (LX , R ) ∂R + −

—   Closed economy labor market equilibrium for given commodity prices and specific factor endowments: see next figure

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w

X

Total Income of S Total Income of R

wY ∂FY pY ∂LY

=

w LY

pX

LX Wage bill of sector X

∂F X ∂L X =

LX w Wage bill of sector Y

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—  2. The Impact of the Trade Liberalization —  Same kind of production frontiers as in the HO model (labor marginal productivity is not constant) ⇒ a country exports the good whose price increases and imports the other one ⇒ gains from trade for the country as whole or for a consumer that owns factors in the same proportions as the country

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—   More intricate problem: to determine in which country the price is lower under autarky (to determine trade patterns)

—  Assume: p Y constant and p X increases ⇒ the country exports good X

⇒ 

⇒ 

∂F X pX ∂L X ∂FY pY ∂LY

shifts uniformly upward

is left unchanged

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Increase in pX

w

w

w

*

w

A

LY

C

A A X

T X

L L

wY

LX 9

A → B: no Labor mobility B → C: Labor mobility

w

w w

LY

wY

X

X A

B

C

A A X

* X

L L

w* wY LX

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—  Trade liberalization implies A → C, which can be decomposed in: —  A → B: no labor mobility between sectors

⇒ the wage increases in the sector whose price increases ⇒ w X increases ⇒ no change in sector Y ⇒ w constant Y —  B → C: labor mobility ⇒ labor moves towards sector X in which wages are higher ⇒ LX increases, LY decreases ⇒ labor productivity decreases in sector X and increases in sector Y ⇒ new equilibrium wage

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—  Changes in nominal returns (s, r : nominal returns to S and R, respectively) —  w increases

—  r  increases (as LX and pX increases ⇒ marginal productivity in value of R ∂FX increases) p ( L , R) X

∂R

X

—  s decreases as LY decreases ⇒ decreases marginal productivity of S )

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n  Grains from trade: pY constant, pX increases n  in terms of Y, real gains = nominal gains üS owners lose üR owners gain ü labor owners gain

n  in terms of X: üS owners lose (nominal return decreases and price increases) üR owners gain (LX increases ⇒ capital intensity decreases ⇒ productivity that is equal to the real return of R in sector X increases) ü labor owners lose with the same reasoning

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⇒ S owners lose from free trade ⇒ R owners gain from free trade ⇒ ambiguous effect for labor owners: gain in term of good Y and lose in terms of good X ⇒ the total effect depends on preferences

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—  3. What About the Free Trade Theorems of the HO Model? —  3.1 ”Lemmas”: Impact of the increase in a factor endowment at fixed commodity prices

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3.1.1. Increase in the endowment in S,

w

wY

X

*

w ' * w

LY

S

B

*

A '

LX LX

w ' * w

LX

Expansion of sector Y, increase of w 16 and decrease of r and s

—  Decrease in s: —  when S increases, the marginal productivity of labor for a

given L increases and the marginal productivity of S decreases ⇒ given L, wX