let Prob be Probability of Special_SigmaField2 ; for n being Nat
for r being Real st r > 0 holds
for jpi being pricefunction
for d being Nat
for RV being Real-Valued-Random-Variable of Special_SigmaField2 st RV = {1,2,3,4} --> ((jpi . d) * (1 + r)) & RV is_integrable_on P2M Prob & RV is_simple_func_in Special_SigmaField2 holds
jpi . d = expect ((Real_RV (r,RV)),Prob)
let n be Nat; for r being Real st r > 0 holds
for jpi being pricefunction
for d being Nat
for RV being Real-Valued-Random-Variable of Special_SigmaField2 st RV = {1,2,3,4} --> ((jpi . d) * (1 + r)) & RV is_integrable_on P2M Prob & RV is_simple_func_in Special_SigmaField2 holds
jpi . d = expect ((Real_RV (r,RV)),Prob)
set Omega2 = {1,2,3,4};
set F2 = Special_SigmaField2 ;
let r be Real; ( r > 0 implies for jpi being pricefunction
for d being Nat
for RV being Real-Valued-Random-Variable of Special_SigmaField2 st RV = {1,2,3,4} --> ((jpi . d) * (1 + r)) & RV is_integrable_on P2M Prob & RV is_simple_func_in Special_SigmaField2 holds
jpi . d = expect ((Real_RV (r,RV)),Prob) )
assume A00:
r > 0
; for jpi being pricefunction
for d being Nat
for RV being Real-Valued-Random-Variable of Special_SigmaField2 st RV = {1,2,3,4} --> ((jpi . d) * (1 + r)) & RV is_integrable_on P2M Prob & RV is_simple_func_in Special_SigmaField2 holds
jpi . d = expect ((Real_RV (r,RV)),Prob)
let jpi be pricefunction ; for d being Nat
for RV being Real-Valued-Random-Variable of Special_SigmaField2 st RV = {1,2,3,4} --> ((jpi . d) * (1 + r)) & RV is_integrable_on P2M Prob & RV is_simple_func_in Special_SigmaField2 holds
jpi . d = expect ((Real_RV (r,RV)),Prob)
let d be Nat; for RV being Real-Valued-Random-Variable of Special_SigmaField2 st RV = {1,2,3,4} --> ((jpi . d) * (1 + r)) & RV is_integrable_on P2M Prob & RV is_simple_func_in Special_SigmaField2 holds
jpi . d = expect ((Real_RV (r,RV)),Prob)
let RV be Real-Valued-Random-Variable of Special_SigmaField2; ( RV = {1,2,3,4} --> ((jpi . d) * (1 + r)) & RV is_integrable_on P2M Prob & RV is_simple_func_in Special_SigmaField2 implies jpi . d = expect ((Real_RV (r,RV)),Prob) )
assume ASS0:
( RV = {1,2,3,4} --> ((jpi . d) * (1 + r)) & RV is_integrable_on P2M Prob & RV is_simple_func_in Special_SigmaField2 )
; jpi . d = expect ((Real_RV (r,RV)),Prob)
set myconst = 1 / (1 + r);
Z1:
expect ((Real_RV (r,RV)),Prob) = (1 / (1 + r)) * (expect (RV,Prob))
by ASS0, RANDOM_1:def 2, RANDOM_1:27;
B1:
expect (RV,Prob) = Integral ((P2M Prob),RV)
by ASS0, RANDOM_1:def 2, RANDOM_1:def 3;
reconsider FOmega = {1,2,3,4} as Element of Special_SigmaField2 by PROB_1:5;
D1:
FOmega = dom RV
by FUNCT_2:def 1;
SS:
( R_EAL RV = RV & RV is nonnegative )
then
expect (RV,Prob) = integral+ ((P2M Prob),(R_EAL RV))
by D1, B1, MESFUNC6:82;
then Q3:
expect (RV,Prob) = integral' ((P2M Prob),(R_EAL RV))
by MESFUNC5:77, MESFUNC6:49, ASS0, SS;
set myr = (jpi . d) * (1 + r);
d in NAT
by ORDINAL1:def 12;
then TT:
0 <= jpi . d
by FINANCE1:def 2;
( ( for x being object st x in dom (R_EAL RV) holds
(R_EAL RV) . x = (jpi . d) * (1 + r) ) & dom (R_EAL RV) in Special_SigmaField2 & 0 <= (jpi . d) * (1 + r) )
by ASS0, FUNCOP_1:7, TT, A00;
then Q4:
expect (RV,Prob) = ((jpi . d) * (1 + r)) * ((P2M Prob) . (dom (R_EAL RV)))
by Q3, MESFUNC5:104;
( dom (R_EAL RV) = {1,2,3,4} & {1,2,3,4} = [#] Special_SigmaField2 )
by FUNCT_2:def 1;
then
expect (RV,Prob) = ((jpi . d) * (1 + r)) * 1
by Q4, PROB_1:30;
then Spec:
expect ((Real_RV (r,RV)),Prob) = (jpi . d) * ((1 / (1 + r)) * (1 + r))
by Z1;
1 = (1 * (1 + r)) * ((1 + r) ")
by XCMPLX_1:203, A00;
hence
jpi . d = expect ((Real_RV (r,RV)),Prob)
by Spec; verum