According to the law of large number, the mean should converge to BS formula. With small number of simulations, anything can happen.
nbfyjhz 发表于 2010-12-28 16:55 
dear fellow students:
i have a question about the value of the put option.
i have two methods: 1: B-S model, using the solution of SDE, carry out 500 simulations 2. use the B-S formula,
both of them have the same mu, sigma. S0 and r, T
why the mean of simulation is lower than the B-S formula
thank you very much
Best regard!