TY - GEN
T1 - Exploiting symmetry in the planning graph via explanation-guided search
AU - Zimmerman, Terry
AU - Kambhampati, Subbarao
PY - 1999/1/1
Y1 - 1999/1/1
N2 - We present a method for exploiting the symmetry in the planning graph structure and certain redundancies inherent in the Graphplan algorithm, so as to improve its backward search. The main insight underlying our method is that due to these features the backward search conducted at level k + 1 of the graph is essentially a replay of the search conducted at the previous level k with certain well-defined extensions. Our method consists of maintaining a pilot explanation structure capturing the failures encountered at previous levels of the search, and using it in an intelligent way to guide the search at the newer levels. The standard EBL and DDB techniques can be employed to control the size of the pilot explanation. The technique has been implemented in the EGBG system, and we present a preliminary empirical study.
AB - We present a method for exploiting the symmetry in the planning graph structure and certain redundancies inherent in the Graphplan algorithm, so as to improve its backward search. The main insight underlying our method is that due to these features the backward search conducted at level k + 1 of the graph is essentially a replay of the search conducted at the previous level k with certain well-defined extensions. Our method consists of maintaining a pilot explanation structure capturing the failures encountered at previous levels of the search, and using it in an intelligent way to guide the search at the newer levels. The standard EBL and DDB techniques can be employed to control the size of the pilot explanation. The technique has been implemented in the EGBG system, and we present a preliminary empirical study.
UR - http://www.scopus.com/inward/record.url?scp=0032596420&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0032596420&partnerID=8YFLogxK
M3 - Conference contribution
AN - SCOPUS:0032596420
SN - 0262511061
T3 - Proceedings of the National Conference on Artificial Intelligence
SP - 605
EP - 611
BT - Proceedings of the National Conference on Artificial Intelligence
PB - AAAI
T2 - Proceedings of the 1999 16th National Conference on Artificial Intelligence (AAAI-99), 11th Innovative Applications of Artificial Intelligence Conference (IAAI-99)
Y2 - 18 July 1999 through 22 July 1999
ER -