%0 Generic %D 2006 %T Membrane Computing and Economics: Numerical P Systems %A Gheorghe Paun %A Radu Paun %C Warsaw, Poland %I IOS Press %K economics %K Membrane computing %K Turing computability %K Universality %N 1-2 %P 213-227 %U http://portal.acm.org/citation.cfm?id=1231159.1231179&coll=GUIDE&dl=GUIDE&CFID=1691426&CFTOKEN=24108515 %V 73 %X With inspiration from the economic reality, where numbers are basic entities to work with, we propose a genuinely new kind of P systems, where numerical variables evolve, starting from initial values, by means of production functions and repartition protocols. We prove that non-deterministic systems of this type, using polynomial production functions, characterize the Turing computable sets of natural numbers, while deterministic systems, with polynomial production functions having non-negative coefficients, compute strictly more than semilinear sets of natural numbers. A series of research topics to be addressed in this framework are mentioned.