Relationship Between Prices and Wages
by Steven Suranovic ©1997-2006
The Ricardian model assumes that the wine and cheese
industries are both perfectly competitive. Among the assumptions of perfect
competition is free entry and exit of firms in response to economic profit.
If positive profits are being made in one industry then, because of perfect
information, profit-seeking entrepreneurs will begin to open more firms
in that industry. The entry of firms however, raises industry supply which
forces down the product price and reduces profit for every other firm in
the industry. Entry continues until economic profit is driven to zero. The
same process occurs in reverse when profit is negative for firms in an industry.
In this case firms will close down, one by one, as they seek more profitable
opportunities elsewhere. The reduction in the number of firms reduces industry
supply which raises the products market price and raises profit for all
remaining firms in the industry. Exit continues until economic profit is
raised to zero. This implies that if production occurs in an industry, be
it in autarky or free trade, then economic profit must be zero.
Profit is defined as total revenue minus total cost. Let represent profit in the cheese industry. We can write this as,
where PC is the price of cheese in ($/lb), wC is the wage paid to workers in ($/hr), PCQC is total industry revenue, and wCLC is total industry cost. By rearranging the zero profit condition we can write the wage as a function of everything else to get,
Recall that the production function for cheese is . Plugging this in for QC above yields,
If production occurs in the wine industry then profit will be zero as well. By the same algebra we can get :
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