1. The problem statement, all variables and given/known data Which branch of mathematics predominates in the equation below? 2. Relevant equations Source: http://en.wikipedia.org/wiki/Taylor_rule 3. The attempt at a solution I know that a line over a number can mean either a statistical mean or a complex conjugate, and that a star in the exponent of a number is usually used to specify either a complex conjugate or delta x in Riemann sums. Which is the case in this equation? I think that it's most likely complex conjugate notation, but I'm not sure. Oh, and the main question is: Which branch of mathematics predominates in this equation?