Conditional Expectation - Basic Properties

Basic Properties

Let (Ω, M, P) be a probability space, and let N be a σ-subalgebra of M.

  • Conditioning with respect to N  is linear on the space of integrable real random variables.
  • More generally, for every integrable N–measurable random variable Y on Ω.
  •   for all BN and every integrable random variable X on Ω.
  • Jensen's inequality holds: If ƒ is a convex function, then
  • Conditioning is a contractive projection
for any s ≥ 1.

Read more about this topic:  Conditional Expectation

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