Page 94 - Kỷ yếu hội thảo khoa học lần thứ 12 - Công nghệ thông tin và Ứng dụng trong các lĩnh vực (CITA 2023)

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Aggregation Methods in the Wisdom of Crowds:

A Literature Review

Thanh Trung Nguyen , Hai Bang Truong
2
1
1 Faculty of Information Technology, Ho Chi Minh City University of
Foreign Languages and Information Technology, Vietnam
trungnt2@huflit.edu.vn
2 Saigon International University, Ho Chi Minh City, Vietnam
truonghaibang@siu.edu.vn

Abstract. The phenomenon of the Wisdom of Crowd has been observed in
several problem domains where the collective opinions of groups tend to be
more accurate than those of individuals. In this context, the aggregation of
individual opinions is a crucial factor that determines the success of unleashing
the wisdom of the crowd. This paper aims to conduct a literature review on
various aggregation methods employed in recent researches. We found that
despite the increasing number of studies that deal with large and intricate
datasets, conventional aggregation methods such as arithmetic, geometric,
weighted aggregation, and mode continue to be widely used in the field of
Wisdom of Crowds.

Keywords: Wisdom of Crowd, Aggregation methods, Arithmetic average,
Geometric average, Weighted average.

1 Introduction

The concept of Wisdom of Crowds refers to the approach of the aggregation of
multiple individual estimates to obtain a better collective one. Such an approach can
outperform individuals, even domain experts, in various prediction and estimation
tasks [1]. Surowiecki claims that a mathematical or statistical aggregation over the
judgments of a group of individuals can be more accurate than those of the average
individuals because of the benefit of error cancellation [1]. In his work, he describes
four characteristics that make a crowd intelligent. First, the group should be diverse,
as this allows for various individuals to complement each other by contributing
unique pieces of information. Second, a decentralized structure is crucial for the
group, without any centralized authority directing or influencing the answers of
individuals. Third, it is also essential that the individuals within the crowd act
independently of one another. Fourth, when the information of many individuals is
pooled, they must be aggregated into a collective opinion, with numerical
contributions and statistical methods often serving as the basis for aggregation. While
diversity, independence, and decentralization are important factors, the aggregating
method plays a key role in consolidating and synthesizing the individual opinions and

CITA 2023 ISBN: 978-604-80-8083-9