1/4  and labor market slack; the markup, too, is important because it varies over time depending on changes in the competitive environment, expected future costs, and other factors.
At first glance, the empirical structural models currently favored in academic research and discussed at this conference--such as the New Keynesian Phillips curve--appear to conform to the informal policymaker model: Expectations formation is dealt with formally, and price inflation, at least in some empirical representations, is directly tied to measures of unit labor costs.