As a marketing concept, consumers’ behavior covers a lot of elements that involve in the consumption processes. As Solomon(2007) stated consumers’ behavior was a serious of processes which include purchasing, using, or disposing of products, services, ideas, or experiences to satisfy their desires and needs. The consumers’ behavior is also considered involving interactions and exchanges (Peter and Olson, 1993). For the interactions, the target market and what the consumers really need must be well known and understood by the marketers (Peter and Olson, 1993). However, it is not only related with the consumers’ experiences during the purchase processes, such as their feelings, thoughts and actions, but also some external factors, like the brand, packaging, price, advertising and so forth. Meanwhile, references group, culture background, economic circumstances and social status, especially the advertisement, and so on, are all deemed to be the factors which influence consumers’ decision.
When you think about reference groups, there are a number of perspectives that one has to consider. According to Hawkins (2010), a reference group is a group whose presumed perspectives or values are being used by an individual as the basis for his or her current behavior. Thus, a reference group is simply a group that an individual uses as a guide for behavior in a specific situation (p.227).
From a marketing perspective, reference groups are groups that serve as frames of reference for individuals in their purchase or consumption decisions. Reference groups that influence general or broadly defined values or behavior are called normative reference groups. Reference groups that serve as benchmarks for specific or narrowly defined attitudes or behavior are called comparative reference groups. A comparative reference group might be a neighboring family whose lifestyle appears to be admirable and worthy of imitation. Normative reference groups influence the development of a basic code of behavior. Comparative reference groups influence the expression of specific consumer attitudes and behavior. The meaning of “reference group” has changed over the years. Originally, reference groups were narrowly defined to include only those groups with which a person interacted on a direct basis. The concept gradually has broadened to include both direct and indirect individual and group influences.
Indirect reference groups consist of those individuals or groups with whom a person does not have direct face-to-face contact, such as movie stars, sports heroes, political leaders, TV personalities, or even a well-dressed and interesting looking person on the streets. However, references a person might use in evaluating his or her own general or specific attitudes or behavior vary.
These Groups may be classified according to a number of variables. Four criteria are particularly useful: membership, strength of social tie, type of contact, and attraction.

THE INFLUENCE OF REFERENCE GROUPS

Reference groups influence consumer behavior in two ways:
1) They set levels of aspiration for the individual, i.e. they offer clues as to what Lifestyle should be led.
2) They define the actual items/services considered acceptable for displaying those aspirations—the kind of housing, clothing, or car, for example, deemed appropriate for a member of the group. Consumers also look to reference groups for guidance and advice. Reference groups are usually small groups, and are not as broad as an entire social class. The reference group concept was, in fact, originally developed in connection with small groups. These include the family, close friends, neighbors, religious groups, work groups and also, athletic groups. The family is recognized as an important reference group. In addition, various family members may play different roles in the purchase consumption process. Like the family, there are several other social groups that have an enormous influence on our lives. They regulate our lives through establishing standards of dress and conduct, and the accomplishment of tasks on a face-to-face basis. Issues of importance to marketing concerning reference group influence can be summed up into three questions.
What influence do reference groups exert on individuals?
How does reference group influence vary across products and brands?
How Reference Groups Influence Consumption?

Reference groups affect consumers through a variety of means:
Through norms,
Through information, and
Through influencing the value expressive needs of consumers.
They influence consumers through bringing about attitude changes by encouraging the expression of certain values and attitudes expressed through the group. Because an individual wants to be a part of a group, he or she will be influenced by the values and attitudes of the group. Furthermore, groups whose members exhibit similar social characteristics are more susceptible to attitude change than groups whose members are less homogeneous. Thus people frequently buy products that others in their group buy. Individuals who feel a strong sense of identification with a group do so because they derive strong psychological or material benefit from being associated with the group.

Figure 1.1 "Reference Group and Social Influence" provides an overview of reference group influences and the ways in which they affect behavior.

This figure summarizes the connections between social groups and consumer attitudes, values, beliefs, and behavior. A social norm is any rule of behavior for meeting societal expectations. All members of a group must adhere to the normative system established for that group. To enforce normative systems, groups tend to exert conformity pressures, either direct or indirect, on their members. Such pressures are actions taken to encourage or force members to act, think, and/or express themselves in certain ways. A college peer group may find one member’s choice of clothing unacceptable and subject that member to ridicule until the accepted dress code is adopted.
Those who seem to feel the most pressure to conform are newcomers to a group who are attempting to establish themselves as legitimate members.
The difference between the price we pay for conformity (loss of freedoms, time commitment, financial commitment, etc.) and the rewards obtained for doing so (levels of acceptance, advancement within the group, prestige gained, etc.) determines for each of us whether we will conform to group expectations and to what extent.
Aware of the desire to conform, marketers typically offer products that are a visible statement of that conformity. Moreover, by showing their products within a group setting, being used by people typical of the group, advertising plays on the consumer’s desire to conform.
Reference Group Types
Reference groups are of two types: primary and secondary.
A primary reference group:
This is one with which the members have frequent face-to-face contact and are close knit. Families, households, study groups, work teams, roommates, and fishing pals are all primary groups. Members exert considerable influence on one another, including marketplace influence, simply because they are significant in one another’s lives.
A secondary reference group:
This is one in which interaction with other members is less frequent. Professional organizations, church congregations, large social clubs, and alumni associations are examples. Secondary groups are often made up, however, of several smaller primary groups.
Reference groups are also either formal or informal.
A formal group
This is one in which there is some sort of structure and, in some cases, for which there are specific membership requirements. To join a civic club you may have to make a formal application, be voted in, and pay dues. To join a professional club, you may have to meet educational requirements. If the club runs regularly scheduled luncheons each month, you are likely to be obligated to attend, particularly if the club is both formal and primary.
An informal group
This is one that has no special membership or attendance requirements other than common interests. Walking clubs, reading groups, and mother-and-toddler play groups are typical examples. Although they may be primary, the groups do not have rigid schedules or rules.
Therefore all the above mentioned primary, secondary, formal, and informal—are all membership groups where a membership group is one to which a person currently belongs. A group that a person would like to be part of, but to which she or he does not currently or may never belong, is known as an aspirational group. Here individuals may attempt to emulate group members by taking on the “cloak of membership”—that is, by dressing, acting, and even thinking the way they perceive members do. Classifying consumers according to aspirational groups allows marketers to create special appeals. Think of the products or services endorsed by athletic or entertainment superstars. Such products are positioned to appeal to people or consumers who want to be like their hero e.g Paul Tergat Johnny Walker commercial.
Other reference groups are dissociative. A dissociative group is one that individuals avoid or deny connections with. Examples would include a political party with which a person would never wish to be connected, an ethnic group, or a hate group like the “rivalry groups” e.g. Anti-socialites, anti ODM, anti-Jubilee.

Reference Group Influences
There are several ways of viewing reference group influence
Reference Groups as Part of the Socialization Process it is through the process of socialization that we learn the norms, appropriate behavior patterns, and values of a society or of a group within it. As part of a reference group, we may be socialized by observing “correct” group behavior and emulating it. Some groups formally teach new members about these things. As part of a reference group, we may be the ones to pass on appropriate role behavior and values. Often, the latter are reflected in purchase choices, and marketers attempt to position their products and services appropriately. Retailers, for example, may advertise the type of shoes most popular with college students to show freshmen the styles that will help them fit in on campus, thus accelerating socialization. E.g Supra shoes among freshmen in campuses across Nairobi. Reference Groups as Setters of Roles
Roles are behavior patterns that people are expected to carry out based on the positions they hold within groups. Members of the group expect certain behaviors and feel the need to conform to them.
Reference Groups as Information Sources
When a reference group is used as an information source, individuals obtain and use all types of information from group members. Information is gathered either verbally or in writing from the group or by direct demonstration, instruction, or observation of group members.

Reference Groups as Normative Influences
Members of the group are influenced by the system. Individuals act in ways that will meet the normative system expectations of the group. The reward for this conforming behavior is increased group acceptance. If norms are not accepted or acted on, rewards may be withheld or sanctions imposed.
Reference Groups as an Expression of Self-Value
Members of the group are influenced by the system. Individuals act in ways that will meet the normative system expectations of the group. The reward for this conforming behavior is increased group acceptance. If norms are not accepted or acted on, rewards may be withheld or sanctions imposed.

In conclusion

The influence of reference groups on marketplace decisions varies. Overall, groups tend to be more influential on product decisions than they are on either brand or outlet choices. Group influence on choice depends on whether a product is privately or publicly consumed (its visibility) and whether it is classified as a necessary or a luxury.
Group influence is greatest for products and brands that are luxuries and highly visible while nonvisible, non-luxury purchases such as bed mattresses are barely subject to group influence at all, since it is unlikely group members will see this product.