causal mechanism and suffers from circular logic. John Montgomery writes that "what Florida has devised is a set of indices which simply mirror more fundamental truths about creative milieux or dynamic cities." Montgomery also disagrees with the cities that Florida designates as most creative, writing that London, not Manchester and Leicester, should be one of the top in the U.K. A critique of Florida's research and theoretical framework has been developed by Matteo Pasquinelli (2006) in the context of Italian Operaismo. Statistical indices and composition Scholars in the disciplines of economics, geography, sociology, and related social sciences have challenged Florida's conception of the "creative class", particularly for the perceived fuzziness of the concept and the lack of analytical precision. A number of studies have found problems with Florida's statistical indices. Hoyman and Faricy, using Florida's own indices, find no statistical evidence that cities with higher proportions of Creative Class workers correlated with any type of economic growth from 1990–2004. By using metropolitan areas as the unit of analysis, the high degree of socio-spatial variation across the metropolitan region is ignored. Studies and popular accounts have questioned whether the creative class is more likely to live in the homogenous, low-density suburban periphery. Social scientists have also identified problems with the occupational composition of the creative class. Economic geographer Stefan Kratke challenges the inclusion of financial and real estate professionals within the creative class on two accounts: 1) these individuals played a decisive role as the "dealer class" in the 2007 financial crises, and therefore cannot be considered a basis for sustainable urban and regional economic growth; and 2) the financial and real estate industries (especially in headquarter cities) are economically significant regional/urban players only because they are largely "reliant on inflows of wealth created by productive activities in other regions." Moreover, Kratke argues that the "political class" is also ill-suited to be included within creative class, as they are, in many cases, implicated in neoliberal financial deregulation and the rise in highly unstable urban and regional growth regimes evident through real estate bubbles across the United States and in other countries. In "Urban Development and the Politics of the Creative Class", Ann Markusen argues that workers qualified as being in the Creative Class have no concept of group identity, nor are they in occupations that are inherently creative. Markusen also notes that the definition of the Creative Class is based largely