Data collection method

3.4.1. Types of data

In general, secondary and primary data are two main types of data with its own advantages and disadvantages.

a. Secondary data

Secondary data is normally known as the data collected by other researchers in their prior research for different purposes and is currently being re-analyzed (Saunders et al, 2007) Secondary data consist of not only qualitative but also quantitative data which could be either raw data or published data. It has variety of sources to select from including journal articles, conference reports, published books, media or the Internet.

Numerous advantages are brought by applying secondary data in comparison with the primary one. Firstly, using secondary data will save more time than using primary data as secondary one is prepared to use without long data collection procedure (Church, 2001).. In addition, secondary data is enabled to be not limited by the geography boundaries as primary

data under the application of e-searching tools (Srivastava and Rego, 2011). Moreover, applying secondary data will bring economy because some of them are provided freely in the Internet or libraries of universities.

However, the researchers should look back some several drawbacks of secondary data. Initially, because of the huge secondary information available, it is difficult to assure the reliability and accuracy of the collected data which requires a careful selection and great e-searching skill. Secondly, it is inappropriate to use secondary data for the new research objectives as it was previously collected by other purpose. That makes researcher find difficult to control the secondary data to fit his own research design. Finally, while using secondary data, the issue of authenticity and copyright should also be taken notice of

In this research, the company‟s marketing department provided secondary data which will be analyzed and presented under the forms of tables and charts. Lately, to provide a sound theoretical framework for the research, secondary data from other sources such as books and the Internet will also be used.

b. Primary data

Primary data, however, is the data originated from the direct data collection of the researcher which is analyzed the first time in researcher‟s work (Srivastava and Rego, 2011).

When the researcher could not find any secondary data which fits the purposes of his research, primary data is gathered under the application of numerous tools and techniques.

Different from secondary date, whatever data the researcher collect directly and is analyzed on the very first time of researcher‟s work is called primary data, following Srivastava and Rego (2011). The primary data will be the other alternative for the researcher in case there is no secondary data meet the requirements of his research.

Primary data is shown its advantages as it addresses the specific matters in the research. That explains why collected data will be perfect for the research design. In addition, the primary data is original; it promotes and guarantees the innovation of a research as a result. Of course, drawbacks are inevitable. The way to apply this kind of data has to challenge with a lot of difficulties. In detail, the research used primary data is more expensive and time-consuming than the one applied secondary data only. Besides, the researcher has to conduct the research within geographical boundaries.

The main methodology of this research is quantitative method. The primary data is

dissertation. A questionnaire is designed and sent out to 100 customers of DABACO Company in Viet Nam to study the customers‟ evaluation about the brand equity and its impacts on their purchasing decisions.

Quantitative method is the main methodology of this research. The questionnaire survey during the writer‟s period of conducting this dissertation collects the primary data. To investigate the customers‟ evaluation about the brand equity and its impacts on their purchasing decision, 100 customers of DABACO Company in Vietnam are received a questionnaire. One of the most popular methods of collecting primary data is survey questionnaire which is mostly applied in descriptive and explanatory research (Saunders et al, 2007).

There are two main kinds of survey questionnaire includes Self-administered and interviewer administered questionnaire. In this research, self-administered questionnaire is used due to several reasons.

First of all, mostly closed end questions is listed in self-administered questionnaire that helps to save time and is quicker to be conducted. The interviewer administered questionnaire find challenging when conducting in geographically separated circumstance.

Secondly, self-administered questionnaire might prevent the interviewer from containing subjective bias.

Finally, self-administered questionnaire allows respondents to complete the survey whenever they want which could bring more accurate results.

3.4.2. Sampling Technology

Beside qualitative and quantitative research, sampling technique is very important to gather accurate data. Compare with qualitative and quantitative research, sampling technique is very important to gather accurate data.

Sampling technique has 2 main types: probability sampling and non-probability sampling (Saunders et al, 2009). The whole sample population is considered as its sample by probability sampling. However, respondents from different groups of the total population are selected by non-probability sampling. The customers of DABACO brand in Viet Nam are the sample population for the research. However, it is too large to select the sample population as the sample size of the research. Therefore, to define the sample size of the research, the author has applied non-probability technique

3.4.3. Questionnaire design

Self -administered questionnaire and interviewer-administered questionnaire are two main types of questionnaire. The author has chosen the self-administered questionnaire for the research, after considering the advantages and disadvantage of the two types of questionnaire. Firstly, it will be quick and cheaper to conduct in a large geographic area by self-administered questionnaire. In addition, another advantage of self-administered questionnaires is anonymity which makes participants to have the honest answers and avoid the bias ones. Last but not least, the respondent will feel more convenient as they can complete the survey whenever they want. Finally, the questionnaire is translated into Vietnamese and designed with mostly closed-ended questions so that the respondent can comprehend the questionnaire.