:: deftheorem defines -random_variable-like FINANCE1:def 5 :
for Omega, Omega2 being set
for Sigma being SigmaField of Omega
for Sigma2 being SigmaField of Omega2
for X being Function of Omega,Omega2 holds
( X is Sigma,Sigma2 -random_variable-like iff for x being set st x in Sigma2 holds
X " x in Sigma );