SIAC Seminar

TITLE: Graph-based methods for efficiently constructing
factorial designs

SPEAKER: Dr. Abhishek K. Shrivastava

ABSTRACT:

Fractional factorial designs are among the most popular
class of experimental designs among practitioners. Usually, a factorial design
is selected after comparing all the designs in a catalog of designs for a given
size. Designs in these catalogs should be distinct under relabeling of factors,
level labels and run order, i.e., they should be mutually non-isomorphic.
Testing two designs for isomorphism is computationally hard, and construction
of non-isomorphic catalogs is even tougher with the large number of designs
that need to be compared for isomorphism. In this talk, I will present a new
approach for solving design isomorphism by representing designs as graphs. The
resulting graph isomorphism problem can be efficiently solved using methods
available in literature. Further, in the case of regular designs, I will show
how these graph representations can be exploited for speeding up the efficiency
of catalog construction by reducing the number of isomorphism tests. I will
demonstrate the gains from this approach by presenting results for 2-level regular
fractional factorial and 2-level split-plot designs.

Bio:

Abhishek K. Shrivastava is an Assistant Professor in the
Department of Manufacturing Engineering and Engineering Management in City
University of Hong Kong, Hong Kong. He received his B. Tech. (Honors) in
Industrial Engineering from I.I.T. Kharagpur, India, in 2003, and his Ph.D. in
Industrial Engineering from Texas A&M University, College Station, USA, in
2009. His research interests are in statistical modeling and analysis of
complex systems, design of experiments and rare event detection. He is a member
of INFORMS, IIE, ASA and IMS.