Other empirical studies, such as those conducted by Norton (1992), have found statistically significant relationships between the density of telecommunication lines and economic growth rates. The idea is that telecommunication services help to reduce transactional and information costs that then exert a positive influence on mean investment ratios, which in turn lead to growth. While there are cogent criticisms of this analysis (for instance, concerning the methodological adequacy of and problems with the econometric techniques used), these studies nonetheless begin to guide our understanding about the role that telecommunication and ICTs can play in economic transformation, especially in the global South.