Properties of a renewal process approximation for a spin market model
  In this short note we investigate the natur of the phase transitions in a spin market model as a function of the interaction strength between local and global effects. We find that the stochastic dynamics of this stylized market model exhibit a periodicity whose dependence on the coupling constant in the Ising-like Hamiltonian is robust to changes in the temperature and the size of the market. 
Muffasir Badshah, Robert Boyer and Ted Theodosopoulos