Main research question
What is the role of customer reviews on purchasing decision and subsequent
developing of a buying behavior of dietary supplement products on Amazon.com?
Sub research questions
4.1 What are the important factors for writing negative and positive reviews on dietary
supplement products on Amazon.com?
4.2 How do the results of Sentiment Analysis (SA) of customer reviews will help to raise
the sales of dietary supplement products on Amazon.com?
4.2 How do the results of Sentiment Analysis (SA) help businesses on Amazon.com to
address negative and positive reviews of dietary supplements?

Research Objectives
1. To implement Sentiment Analysis (SA) of customer reviews on dietary
supplement products on Amazon.com over the last two years.
2. To investigate the factors impacting the purchasing decision and subsequent
buying behavior of dietary supplements on Amazon.com through a result of the
analysis.
3. To look at the difference between the Sentiment Analysis (SA) and the thematic
analysis of the customer reviews on dietary supplement products on
Amazon.com.
4. To recommend business insights as the result of Sentiment Analysis (SA) for
existing and new businesses on Amazon.com.

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Purpose of the study
The purpose of the study is to analyze customer reviews on dietary supplement
products on Amazon.com over the last two years. It is vital to study and analyze the
components of written customer review of the product to reveal the factors affecting the
initial purchasing decision and subsequent buying behavior. By the nature, a person will
be more meticulous towards purchasing the product directly related to the health and
well-being and indeed will spend time to read the reviews of other customers who have
an experience of purchasing and using the supplement. The trend of following the
healthy lifestyle mostly influenced by external factors such as celebrities, influencers on
social media channels and advertisement have boosted the production and sales of
dietary supplement products in the US in the last few years. Undoubtedly, the direct
effect of SARS-CoV-19 is unavoidable and have ‘pushed’ individuals to act on their
instincts and start purchasing the healthy additives, such as herbs, pills, gummies and
others. It is important to relate and further analyze and study the positive and negative
reviews of customers on dietary supplement products on Amazon.com to initiating
purchasing decision and building a buying behavior. Moreover, the outcomes of the
study will help businesses on Amazon.com to reveal and focus on components which
have prompted to write a negative or positive review on a product. Thus, the businesses
who produce and sell dietary supplement products on Amazon.com will have tools to
raise the product sales.
Research Method and Design
The major reasons for following the Mixed-Method Research Approach will be justified
by implementing Qualitative and Quantitative research design approaches as part of
this study. There are diverse Qualitative and Quantitative methods for the data
collection, such as, interviews, questionnaires and observations. As part of this study
semi-structured interviews with the list of prepared questions and topics will be
conducted. As credibility and reliability are important aspects of the study, the semi-
structured interviews will increase the credibility and reliability of the data. Semi-
structured interviews will be conducted via telecommunications, as Skype or FaceTime.
Stratified sampling method will be used to select interviewees for the semi-structured
interview. For instance, the population of individuals of age from 18 to 45, having stable
income, both females and males, having an experience of purchasing dietary
supplement products on Amazon.com will be the sample group. The Mixed-Method
Research Approach methods and sequential exploratory design will be used as part of
this study to answer the main and sub research questions.
Quantitative data will be collected and analysed that will reveal the results of Sentiment
Analysis (SA). Sentiment Analysis (SA) will be used as the main technique to gather
and analyse the textual information and data on Amazon.com as customer reviews on
dietary supplement products.

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Significance of the Research
The findings revealed throughout this research will add to the literature gap about
purchasing intention and consumer buying behavior of dietary supplement products on
Amazon.com. The factors influencing the positive and negative customer reviews on
product sales will also studied and addressed through the analysis of person-to-person
online interviews. Moreover, the study will help to identify the focal point for marketplace
sellers to raise product sales. The findings of the research could potentially recommend
insights to new marketplace sellers when starting a business on Amazon US.

Trustworthiness
Before and after the data collection, the validity and reliability of the data will be
considered for the further analysis and study. Semi-structured interview will help to
obtain firsthand information directly from the knowledgeable individuals. Interviewing
individuals who purchase dietary supplement products on Amazon.com will help to
obtain a special type of information.

Ethical Considerations
Ethical norms of the research will be throughout the research. For instance, any
personal information of interviewees will not be disclosed in order to keep the
confidentiality of any sensitive information shared. Moreover, the files containing the
voice recordings of interviews held will be deleted after the research is implemented.
Voluntary participation of all fifteen interviewees will followed for the interviews. Prior the
interview, the interviewees will be informed on the purpose, any risks and benefits of the
study. Apart from that, the study will be free of plagiarism or research misconducts and
all results will be accurately represented.

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Timetable for the Research

Assumptions, Limitations, and Delimitations
The term assumption in a research study is the belief of a researcher trying to
determine the relation between two variables. Assumptions could be described as
principles that are being accepted as true based on logic or any other reasons, but
without verification. For instance, it is assumed that prevailing number of females are
purchasing dietary supplement products than males in the US. This assumption could
be classified as an assumption needed to conduct a research. Thus, by relying on this
assumption, ten out of fifteen interviewees will be females.
Limitations could be described as the constraints of the research, specifically, the
aspects of the study not covered for certain reasons. For instance, as part of the study,
people of a certain age group are covered.