 This policy dimension of the creative city concept has been criticized by others as being a tool, not for revitalizing cities, but for the creation of an industry dedicated to offering promises of urban renewal.In Richard Florida's work on creative cities and the creative class, he quantifies various measures of the "creative potential" of a city, and then ranks cities based on his "creativity index".This, in turn, encourages cities to compete with one another for higher rankings and the attendant economic benefits that supposedly come with them.