Quasi-linear utility
The utility functionU(x0,x1,...,xn) = x0 + Σiui(xi), where ui(⋅) are strictly concave functions. This generates demand functions for goods xi that depend only on their own prices in terms of the numeraire x0. That adds to tractability, but unfortunately implies that income elasticities of all goods but x0 are zero.
Quota by country
A quota that specifies the total amount to be imported (or exported) and also assigns specific amounts to each exporting (or importing) country.
Quota rent
The economic rent received by the holder of the right (or license) to import under a quota. Equals the domestic price of the imported good, net of any tariff, minus the world price, times the quantity of imports.