檸檬市場的推導 - 經濟

it is assumed (1) that both type one traders and
type two traders are von Neumann-Morgenstern maximizers of
expected utility; (2) that group one has N cars with uniformly
distributed quality X, 0<=X<=2 , and group two has no cars; (3) that
the price of "other goods" M is unity.
Denote the income (including that derived from the sale of
automobiles) of all type one traders as Y1 and the income of all
type two traders as Y2. The demand for used cars will be the sum
of the demands by both groups. When one ignores indivisibilities,
the demand for automobiles by type one traders will be
Dl = Y1 / P mu / P >1
Dl =0 mu / P <1.
And the supply of cars offered by type one traders is
(1) S2 = pN /2 p <=2 N is the numbers of automobile
with average quality
(2) mu = p / 2.
(To derive (1) and (2), the uniform distribution of automobile
quality is used.)

請問各位,上述的(1)與(2)如何推導而得??

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