How to predict consumers; behaviors? For budget strategy example, it is the budget constraint and it is the amount of general consumers' income have available to spend on the kind of products and services. To maximize general consumer individual enjoyment. Consumers should make sure that they spend their income. So, that the last dollar spent on each product lives them the same marginal utility. The income effect is the change in the quantity demanded of a product that results from the effect is a change in the price on consumer purchasing power. The substitution effect is the change in the quantity demanded of a product that results from a change in price making the product or service more or less expensive relating to other products or services, holding constant the effect of the price change on consumer purchasing power.Therefore, it seems that consumers usually calculate he/she needs to allocate how much income to make budget to spend how much expenditure to buy how much number to the kind of product or consume how many time(s) to the kind of service to satisfy his /her utility needs. This is general consumer individual spending budget psychological attitude or emotion to influence that he/she needs to make choice whether he/she ought spend how much expenditure to buy the kind of product to use or consume the kind of service. Therefore, it the firm can gather how many consumer number has the general income level in society. Then, it can attempt to predict whether how many consumer number will expect to buy the kind of products to use or consume the kind of services to enjoy in the year. It is based on general consumers will need to make budget to spend allocation whether they ought or ought not buy the kind of products to use or consume the kind of services to enjoy in the year. Thus, when the firm can measure whether how many people who own will earn the least income level to own the purchase power to buy the kind of products or consume the kind of services in the year. Then, it can apply this data to analyze whether how much product price or service price level is the most reasonable level to charge consumers in order to achieve the maximum customer number to compare competitors in the similar kinds of products or similar service providers in the market more easily.It bases on demand and supply theory. Because the society has people need to buy any kinds of products to use or consume any kinds of services to enjoy So, social influences will affect consumption choices. Social factors can have an effect on consumption. For example, the amount of utility people receives from consuming a product often depends on how much other people they know who also consume the product. It is a network externality in the consumption of a product, if the usefulness of the product increases with the number of consumers who use it. There is also evidence that people like to be treated fairly.