Dominance-Based Rough Sets for Tehran Seismic Vulnerability Assessment Amiri 1 , A. R., M. R. Delavar 2 , S. M. Zahrai 3 , M.R. Malek 4 I.Hatefi Afshar 1 1: GIS MSc student, Dept. of Surveying and Geomatic Eng., College of Eng. University of Tehran Email: aamiry@ut.ac.ir 2: Assist Prof. , Dept. Of Surveying and Geomatic Eng. , Center of Excellence in Geomatics Eng. And Disaster Management, College of Eng. University of Tehran. Email: mdelavar@ut.ac.ir 3: Assist Prof. , School of Civil Eng. , College of Eng. , University of Tehran, Tehran, Iran Email: mzahrai@ut.ac.ir 4: Assist Prof. , Faculty of Geodesy and Geomatics, KN Toosi. Industrial Univesity, Tehran, Iran Email: mmalek@ut.ac.ir Abstract This paper outlines sorting Tehran blocks in terms of seismic vulnerability using rough set theory. Tehran is located on a number of known and unknown faults and for this reason is vulnerable to earthquake. Therefore, development of seismic vulnerability could help national disaster organization to create and implement a plan to promote awareness of earthquake vulnerability and implementation of seismic vulnerability reduction project in Tehran. One of the methods which construct a comprehensive preference model that could be used to support the sorting task, is dominance-based rough set approach (DRSA). DRSA is an extension of the rough set which has been proposed by Greco et al. (1999). The classic rough set approach can not consider the preferential and order properties of criteria, because it is based on the use of indiscernibility relation. However, our aim is to sort the urban blocks, then we must take into account preference orders in the domains of criteria. DRSA replaces the indiscernibility relation by the dominance relation. In this paper, at first, we make a preference model using preferential information about a number of Tehran blocks given by Tehran seismic vulnerability map prepared using intuistic fuzzy method. Then we achieve a comprehensive preference model in the form of "if…then…" decision rules. These rules are derived from rough approximations of decision classes, where the antecedent (condition part) specifies values assumed by some criteria and the consequence (decision part) specifies an assignment to a few decision classes. The decision classes are the grade of seismic vulnerability in this research. Finally using the decision rules and whole database of Tehran, a sorting seismic vulnerability map is produced and successfully tested. Keywords: Dominance-Based Rough Set, Seismic Vulnerability, Multicriteria Decision Making, Decision Rules, Dominance Relation 1- Introduction One of the most well known risks affecting urban areas is earthquake. Therefore, existing a seismic vulnerability map helps national disaster organizations to create and implement a plan to promote awareness of earthquake vulnerability and implementation of seismic vulnerability reduction project in Tehran. Determination of vulnerability of urban blocks is a multicriteria decision making problem. The multicriteria sorting is defined as assigning a set of objects described by a set of criteria to one of pre-defined and preference-ordered categories. In this paper, objects