| Who? |
Jacob Viner first examined the specific
factors model, which is a variant of the Ricardian model.
It was further developed by Paul Samuelson and Ronald
Jones. It is also called the Ricardo-Viner model. Michael Mussa (1974)
developed the graphical approach to illustrate the main results of this
model. In contrast to the Ricardian model, this model includes factors
other than labor. |
| Mobile vs Specific Factors |
Thus, there are two types of factors. Labor is the mobile factor that can move between the two sectors. Each
of the other two factors is assumed to be specific to a
particular industry. That is, the quantity of each specific factor is fixed
and cannot move to the other industry. Specific factors cannot move between
industries.
Examples of specific factors: climates, soil, skilled workers. |
Assumptions:
2 goods x 3 factors |
K is used in industry 1 only.
T is used in industry 2 only.
Labor is mobile.
The economy produces two goods using two factors of production,
capital and labor in a perfectly competitive market. Capital is assumed
to be specific to each industry, and is immobile between industries. In
the two good model, there are two specific factors, K and T.
In this sense, Jones calls it a 2-good, 3-factor model.
(K = Kapital, which is capital in German, T = Terra in Latin, meaning
land or earth. We do not use L to denote land because it is reserved for
labor, and the lower case l looks like "one." It is best to
avoid confusing symbols.) |
Example

|
Finland produces ocean cruisers and leather products
such as reindeer fur, mink and fox coats.
Lapland, the nothern part of Finland, is sparsely inhabited
by mostly Indians who hunt these wild animals. This cold climate or forest
is a factor specific in the leather goods industry.
In the urban areas Finns are also engaged in cruise ship
building and Finland exports cruisers to European countries. In addition
to well educated workers, the ship building industry requires a large
amount of capital, which is specific to that industry in that it cannot
be used in the leather goods industry. Finnish workers are mobile between
the two industries. |
 |
Palio in Siena, Italy (2000). Horse trainers are specific
to the horse industry. Jockeys ride horses without saddles. |
| Specific Factors model vs Heckscher-Ohlin |
In a Heckscher-Ohlin model to be studied shortly, both
factors, capital and labor, are assumed to be mobile. Recall that in production
decisions, some factors are fixed (and hence specific) in the short run,
but all factors are variable inputs in the long run. Hence, the HO model
is a long-run model, whereas the specific factors model is a short
run model in which capital and land inputs are fixed but labor is a variable
input in production. |
| Production |
y1 = F(K,L1) y2
= G(T,L2)
In contrast to the Ricardian model, labor is the mobile
factor between the two industries.
Resource constraint:
L1 + L2 = L
π1 = p1y1 - wL1
- rK
Consider a change in the amount of labor employed, ΔL1.
Δπ1 = p1Δy1
- wΔL1 = 0 for a maximum profit (The profit function
must reach a peak or a plateau so that a change in profit is zero)
Divide both sides by ΔL1.
p1MPL1 = w
Alternatively,
p1 = w/MPL1 = MC1 (For
instance, if the marginal worker produced 2 automobiles and got paid $60,000,
marginal cost of the automobile is $30,000).
p2 = p2y2
- wL2 - sT (s = land rental, sT = landlords' income)
p2MPL2 = w.
p1MPL1 = p2MPL2
p1/p2 = MRT = MC1/MC2 |
| |
|
| No specialization |
Diminishing Returns: Marginal product of
labor (or any other input) declines as more is employed. ⇒ PPF is
concave to the origin.!
Unlike in the Ricardian model, labor is shared between
the two industries. Thus, the specific factors model explains why a country
produces a product and also imports it. For instance, the US produces
but also imports oil from the Middle East. |
| No wage equalization |
p2MPL2 = w,
p*2MP*L2 = w*.
Thus, w ≠ w*"
If labor productivities are the same in
the two countries, free trade equalizes wage rates. However, due to diminishing
marginal returns, marginal product of labor decreases with employment.
In general, MPLi is not equal to MP*Li in any industry.
Free trade equalizes output prices, but not wages. |
| Allocation of labor |
 |
| Price effect |
How does a change in the output price affect income
distribution?
An increase in the price of the exportable increases wage.
An increase in the price of the exportable increases
rent.
More generally,
|
| Which factor benefits |
A price increase benefits the specific factor in that
sector.
An increase in the price of a good increases the rent
of the factor specific to that industry.
For instance, international trade raises the price of
the exportable good (foodstuff, such as corn and soybean), which in turn
raises the price of the factor stuck in that industry such as land. That
is, trade raises land value in the Midwest.
The US government now endeavors to achieve energy independence,
i.e., independence from imported oil. Billions of dollars are now being
invested to develop alternative source of energy such as ethanal from
corn or switchgrass. This increase in the price of ethanol should increase
the land value in the Midwest, because it is a fixed factor there.
|
| Effect of Free Trade |
This implies that a movement toward free trade
(FT) increases the price of the exportable (p1), and hence
free trade increases the return to the factor (K) specific to the export sector. |
| |
An increase in the price of the exportable increases
its output. Note that PPF is concave to the origin, unlike that in the
Ricardian model.
 |

The Silkroad |
Silk was invented by the Liangzhu people who settled down
in Liangzhu (near Shanghai now) about 3000 BC. The Liangzhu people was trading
jade artifacts during the Neolithic period (3300-2200 BC) even before their
first dynasty, Xia. In the "Arabian Nights," the story of Aladdin,
a lazy boy in China, indicates that Arabia was an intervening region on
the silk road and Arabia connected China and Africa. Gold, amber, and ivory
were prized in China and imported from Africa. Aladdin itself is either
Persian or Arabic name, meaning "faithful." The intervening regions
also joined the trade on the silk road. |
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