The article presents a new method for estimating continuous time stochastic volatility models without needing option prices or volatility data. By using a modified importance sampling technique and the Euler-Maruyama scheme, the researchers were able to accurately estimate the model. Their Monte Carlo studies showed that the method works well, and empirical applications demonstrated its usefulness. Importantly, the results suggest that the Heston model may not be the best fit for this type of analysis.