[UUID] The consumer decision making process is influenced by various factors, those factors can be summarized as social, psychological and personal factors. Social factors include reference groups and group compliance so that behaviour is influenced by specific values, codes and culture and distinguishes groups from each other.
A family brings its own values, codes and rituals and represent a special reference group with family members frequently exchanging feedback on consumed products and/or future planned purchases. This interaction is a fundamental building block in influencing purchase behaviour within a family.
Various studies showed that the family is changing its structural influence in the society, with in the past holding the traditional role of a providing security is now replaced by a more nuclear family model containing unmarried couples, one-person households or lone-parent families.
Those changes surely influence buying behaviour but as for now we can recognize the traditional family as main collective decision making unit that is distinguish from other reference groups to the extent that a face to face interaction is taken place regularly, subordination of one’s personal consumption goals in connections with the family goals of upcoming buying decisions, products are shared and thereby rules for consumption will influence any decision prior the actual purchase and finally family members can act as purchasing agent for another member of the family.
Particular the last point of being a purchasing agent for another family member, has changed during the last ten or twenty years. In fact that parents spent less time in making purchase decisions for the whole family puts children in a unique position to influence product purchase and diffuse a parents income.
The mentioned factors above will lead to dispute and potential conflict that need to be resolved by its members and resulting in a higher value for compliance compared with other reference groups.
Aside those individual influence factors, a family consists of different stages (family life cycle) where its members pending on age and social status influences others members to change their buying behaviour to reflect a projected social image. This image projection creates expectation on other family members to adapt their social image and buying behaviour.
For example, in the earlier stage of the family life cycle, mother and father are role models in connection on how children perceive decision making and buying behaviour. This influence will deteriorate over time and substituted by media (television, Internet etc.) and other reference groups (friends, school etc.) which will then lead children to influence their parents on product selection and buying behaviour.
A more positive development is that several writers mentioning children as a major driving force when in comes to decisions on environmental friendly products.
In general, less discussion might emerge on commodity products with a lower foothold value but in light of higher value investment such as cars, TV sets or cloth for children discussion are unavoidable as sex-roles and socialization are influencing priorities and affection for alternative products.
For instance, the decision on where to go on holiday is a typical example of a syncratic decision making process, it involves every member of family with opinions differ in length and width so that the process of finding the right solution forces concessions on everybody to ensure family harmony can be preserved.
But of course certain product categories are selected through an autocratic decision where more or less one member of the family is assigned to carry out the responsibility and decision making.
Research on Japan, Family, Purchase behaviour
[Rose, Boush and Shoham, 2002] David Boush, Aviv Shoham, Gregory M Rose, (2002) “Family communication and children’s purchasing influence: a cross-national examination“, Journal of Business Research, 55 (2002) 867– 873 .
[Ogawa and Wan, 2007] Kazuo Ogawa, Junmin Wan, (2007) “Household debt and consumption: A quantitative analysis based on household micro data for Japan“, Journal of Housing Economics Volume 16, Issue 2, June 2007, Pages 127-142 .
Research on China, Family, Purchase behaviour
[Wang, Holloway, Beatty and Hill, 2007] Sijun Wang, Betsy B Holloway, Sharon E Beatty, William W Hill, (2007) “Adolescent influence in family purchase decisions: An update and cross-national extension“, Journal of Business Research, Volume 60, Issue 11, November 2007, Pages 1117-1124 .
 ^ [Blythe, 2005] Jim Blythe, (2005) “Essentials of Marketing“,3rd Edition, Financal Times Management , Chapter 3. ; [Copley, 2004] Paul Copley, (2004) “Marketing Communications Management: Concepts and Theories, Cases and Practices“, Butterworth-Heinemann , Chapter 3. ; [Solomon et al., 2006] Margaret Hogg, Michael R Solomon, Gary J Bamossy, Soren Askegaard, (2006) “Consumer Behaviour: A European Perspective“,3rd, Financial Times/Prentice Hall , Chapter 11.
 ^ [Foxman, Tansuhaj and Ekstrom, 1989] Ellen R Foxman, Patriya S Tansuhaj, Karin M Ekstrom, (1989) “Family Members’ Perceptions of Adolescents’ Influence in Family Decision Making“, The Journal of Consumer Research, Vol. 15, No. 4 (Mar., 1989) (pp. 482-491) . ;[Beatty and Talpada, 1994] Sharon E Beatty, Salil Talpade, (1994) “Adolescent Influence in Family Decision Making: A Replication with Extension“, The Journal of Consumer Research, Vol. 21, No. 2 (Sep., 1994) (pp. 332-341) .