Consumer behavior is the study of individuals, groups, or organizations and the processes they use to select, secure, and dispose of products, services, experiences, or ideas to satisfy needs and the impacts that these processes have on the consumer and society. It blends elements from psychology, sociology, social anthropology and economics. It attempts to understand the decision-making processes of buyers, both individually and in groups. It studies characteristics of individual consumers such as demographics and behavioral variables in an attempt to understand people's wants. It also tries to assess influences on the consumer from groups such as family, friends, reference groups, and society in general.Customer behavior study is based on consumer buying behavior, with the customer playing the three distinct roles of user, payer and buyer. Research has shown that consumer behavior is difficult to predict, even for experts in the field. Relationship marketing is an influential asset for customer behavior analysis as it has a keen interest in the re-discovery of the true meaning of marketing through the re-affirmation of the importance of the customer or buyer. A greater importance is also placed on consumer retention, customer relationship management, personalisation, customisation and one-to-one marketing. Social functions can be categorized into social choice and welfare functions.
Each method for vote counting is assumed as social function but if Arrow’s possibility theorem is used for a social function, social welfare function is achieved. Some specifications of the social functions are decisiveness, neutrality, anonymity,monotonicity, unanimity, homogeneity and weak and strong Pareto optimality. No social choice function meets these requirements in an ordinal scale simultaneously. The most important characteristic of a social function is identification of the interactive effect of alternatives and creating a logical relation with the ranks. Marketing provides services in order to satisfy customers. With that in mind the productive system is considered from its beginning at the production level, to the end of the cycle, the consumer (Kioumarsi et al., 2009).