This work is concerned with the theory of initial and progressive enlargements of a reference filtration F with a random time τ. We provide, under an equivalence assumption, slightly stronger than the absolute continuity assumption of Jacod, alternative proofs to results concerning canonical decomposition of an F -martingale in the enlarged filtrations. Also, we address martingales’ characterization in the enlarged filtrations in terms of martingales in the reference filtration, as well as predictable representation theorems in the enlarged filtrations.
Mots-clés : initial and progressive enlargements of filtrations, predictable projection, canonical decomposition of semimartingales, predictable representation theorem
@article{PS_2013__17__550_0, author = {Callegaro, Giorgia and Jeanblanc, Monique and Zargari, Behnaz}, title = {Carthaginian enlargement of filtrations}, journal = {ESAIM: Probability and Statistics}, pages = {550--566}, publisher = {EDP-Sciences}, volume = {17}, year = {2013}, doi = {10.1051/ps/2011162}, mrnumber = {3085632}, zbl = {1296.60106}, language = {en}, url = {http://archive.numdam.org/articles/10.1051/ps/2011162/} }
TY - JOUR AU - Callegaro, Giorgia AU - Jeanblanc, Monique AU - Zargari, Behnaz TI - Carthaginian enlargement of filtrations JO - ESAIM: Probability and Statistics PY - 2013 SP - 550 EP - 566 VL - 17 PB - EDP-Sciences UR - http://archive.numdam.org/articles/10.1051/ps/2011162/ DO - 10.1051/ps/2011162 LA - en ID - PS_2013__17__550_0 ER -
%0 Journal Article %A Callegaro, Giorgia %A Jeanblanc, Monique %A Zargari, Behnaz %T Carthaginian enlargement of filtrations %J ESAIM: Probability and Statistics %D 2013 %P 550-566 %V 17 %I EDP-Sciences %U http://archive.numdam.org/articles/10.1051/ps/2011162/ %R 10.1051/ps/2011162 %G en %F PS_2013__17__550_0
Callegaro, Giorgia; Jeanblanc, Monique; Zargari, Behnaz. Carthaginian enlargement of filtrations. ESAIM: Probability and Statistics, Tome 17 (2013), pp. 550-566. doi : 10.1051/ps/2011162. http://archive.numdam.org/articles/10.1051/ps/2011162/
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