We purchase various products and services in every day. A process, which selects the product and service by consumer, is called a purchasing decision process. Generally speaking, the purchasing decision process consists of five stages. There are problem cognition, information search, substitute validation, purchasing decision, and action after the purchase. We pay attention to the substitute validation as which a consumer estimates it among two or more alternative related with an item. In this paper, the product selection action of the consumer about the notebook PC in consideration of the synergistic effect of two or more attributes is studied. Further, we analyze the impact of the parameter about a consumer's degree of satisfaction on product selection using sugarscape model.