6533b830fe1ef96bd129726f

RESEARCH PRODUCT

Martingale Convergence Theorems and Their Applications

Achim Klenke

subject

Doob's martingale inequalityUniform integrabilityPure mathematicsDoob's martingale convergence theoremsLocal martingaleAlmost surelyMartingale (probability theory)Stock priceStochastic integralMathematics

description

We became familiar with martingales X=(X n ) n∈N0 as fair games and found that under certain transformations (optional stopping, discrete stochastic integral) martingales turn into martingales. In this chapter, we will see that under weak conditions (non-negativity or uniform integrability) martingales converge almost surely. Furthermore, the martingale structure implies L p -convergence under assumptions that are (formally) weaker than those of Chapter 7. The basic ideas of this chapter are Doob’s inequality (Theorem 11.4) and the upcrossing inequality (Lemma 11.3).

https://doi.org/10.1007/978-1-4471-5361-0_11