1. An exposure apparatus for exposing each of a plurality of regions arranged on a substrate, said apparatus comprising: a measurement device configured to acquire an image signal of an alignment mark formed in the region and to measure a position of the alignment mark based on the signal; and a processor configured to i) cause the measurement device to measure a position of the alignment mark formed in each of at least two regions of the plurality of regions, under a plurality of measurement conditions, ii) calculate a feature value of the signal acquired with respect to each of the at least two regions under each of the plurality of measurement conditions, iii) calculate, with respect to each of the plurality of measurement conditions, a coefficient of a transformation equation which transforms a coordinate of a designed position of the alignment mark to a value that approximate the feature value corresponding to the designed position, the transformation equation being formulated from a coordinate transformation equation which transforms a coordinate of the designed position to a value that approximates a coordinate of the measured position corresponding to the designed position, by replacing the measured position with the feature value, and iv) set a measurement condition, under which the measurement device measures the position of the alignment mark, based on the coefficient calculated with respect to each of the plurality of measurement conditions.