Suppose U is set of objects, E is a set of {0,1}-valued parameters : Z6 A# r A# z, m' q
& q. M b4 y& k4 p
for describing objects in U. For any u in U, define an additive utility * y' ]+ }1 X9 g 5 p4 l0 C6 o! ~( l V8 Dfunction f as follows: ( [3 {2 ?$ S- L& A4 p ?2 l9 e8 @, x" S& F5 @ f (u ) e (u ), (对e属于E,e(u)求和) 7 \* l1 H1 A; A8 A1 C. s/ Y % w( H* [3 S0 j3 }" L# g; O e E , o) U' E, f& E$ h. Q, r! w1 h& z( L4 X0 O
where e(u ) 0,1. u is called an optimal solution if it is one of the ' {0 K7 [2 q+ p. Z- N
3 ?! ^; {% X, B" X$ [9 imaximum points of function f with respect to normal order. For 8 ~. r! M3 J$ R& q) I& g
9 v( f& D/ b2 L6 E0 M U, E: d
certain reasons, some values are missing. It costs if we want to find 5 w- I) M4 X) V& o, U; A. r' ?( O9 c, m. G# @
out what these values are. We assume that we know nothing about ) Z( m# C3 g( R: J( }6 L- b7 K+ Z% |2 {, i& o( t; ]4 G
the probability of these values being 0 or 1. So my questions are: ; G/ @ Z, k) I) U2 G4 U! `" |/ L9 I2 C
(1.) Which unknown value should we figure out firstly if we want to 4 ^# t0 q# U) O9 o* h! Y7 d
% o9 u. n2 g9 t- x( c find at least one optimal solution?