 Blau and Fingerman (2009), drawing from these and other studies, refer to weak ties as "consequential strangers," positing that they provide some of the same benefits as intimates as well as many distinct and complementary functions.In the early 1990s, American social economist James D. Montgomery contributed to economic theories of network structures in labor market.In 1991, Montgomery incorporated network structures in an adverse selection model to analyze the effects of social networks on labor market outcomes.