215 people in 8 districts in HCMC were interviewed. These districts have been chosen because most people gather there to live and work. That is, the consumers around those districts are extremely diverse which will ensure the results of the interviews are not biased. Furthermore, the network of convenience stores in those district is huge.
In this study, two different consumer product categories were selected: washing powder, (a type of cleaning agent) and perfumes. In order to be interviewed, the interviewees must have bought both products no more than 3 months from the present. Moreover, the interviewee must be the person who is responsible for purchasing those categories of products.
Non-probability sampling method is used in this study. Non-probability sampling is a non-random selection which depends upon the biased view of the researcher. Therefore, it is impossible to calculate the probability of any objects included in a sample. This sampling method is preferred because it saves time and money compared to probability sampling. It is easier to use and can be employed when the sample population is relatively small, as is the case of this study. Additionally, non-probability sampling uses
More specifically, this study employs quota sample which is a type of non-probability sampling method often used in market research. The relevant factors such as gender, age range, and family size are controlled to ensure the groups in the sample are corresponding to the groups in the population.1.
Following the criteria (quota and inclusion criteria), a set of 35 questions were sent to selected subjects who satisfy all requirements. The quota criteria are comprised of 3 factors: gender, family size, and city. At least 50% of the sample was women, 30% was single househo