An existingmodel available in literature wasmodified to degrade the accuracy of private
information from an informer, so that he can manipulate the securities market repeatedly in a long
period. The analysis result shows tha,t the informer has tomake the public believe in his honesty to
lead the publics' believes in the assets and manipulate themarke.t The long-period equilibrium of an
informerwhomay change his statuses between honesty and dishonesty is that it is impossible for the
public to fully know his status, information transferkeeps on and his creditability ismore than 1/2.