2 The segment may have influence over other segments. Celebrities are an obvious example, but in the business-to-business world it is common for some companies to have influence or even power over others. For example, when Westinghouse invented air brakes for trains, it targeted a railroad which operated out of Chicago and persuaded it to fit the system. This meant that any other railroad company which intended to run trains through Chicago needed to adopt the same system in order to be compatible with other trains.