Innovative products have received special attention for very long time. Compared to mature products, innovative products exhibit different demand pattern since demand is changing over time throughout the life cycle. Several papers aim at forecasting demand changes. Among these, Rodgers (1976) reviews relevant marketing research on new product adoption and diffusion process. Gatignon and Robertson (1985) provide a framework for diffusion modeling. Brownstone and Train (1998) study how to forecast product penetration with flexible substitutable patterns. They model customer making a purchasing decision among several substitutable products, and apply choice models including “mixed logits” model. Peres, Muller, and Mahajan (2010) provide a recent review on the progress of innovation diffusion and new product growth model. All of these papers study new product demand as a diffusion process, with theoretical roots found in sociology, geology, etc. (Gatignon & Roberston, 1985).