“…DeGraba (2001) asserts that a positive access charge would cause a bias in favor of the technology with high marginal costs because the access charge reflects only the marginal cost. Kim and Lim (2004) argue that the revenue-sharing rule for interconnection charges may give a firm a perverse incentive to raise its own cost in order to grab a higher share of the revenues. Valletti and Cambini (2005) show that firms tend to collude by underinvesting in quality in a two-way interconnection model of telecommunications.…”