A Brattle economist was retained by a tire distributor alleged to have conspired with a tire manufacturer to provide it with more favorable pricing and exclude a rival distributor from the downstream market. Brattle provided an expert report and testimony demonstrating that it was not in the interest of the manufacturer to exclude the rival distributor, and that competition in the downstream market had not been adversely affected by any differences in pricing as the rival distributor had simply switched to selling other brands of tires.