The Measurement of Subjective Probability

Beliefs can be represented with numbers, but what do these numbers mean? There are two main approaches to measuring belief: epistemic and decision-theoretic. Epistemic approaches explain belief measurement by appeal to relations between belief states, while decision-theoretic approaches appeal to relations between beliefs and desires.

Format: Paperback / softback
Length: 90 pages
Publication date: 02 May 2024
Publisher: Cambridge University Press

Beliefs can vary in intensity, and we often quantify these variations using numbers. For instance, we might express confidence in a scientific hypothesis to be 90% true or only 30% likely to succeed in a risky endeavor. However, the significance of these numbers remains a subject of curiosity. What lies behind these numerical representations? More fundamentally, what is the psychological reality that these numbers correspond to? Moreover, how can we differentiate between belief representations that differ only by a small numerical margin? In this Element, we explore the primary methods used to measure belief. These approaches can be categorized into two broad categories: epistemic and decision-theoretic. Epistemic approaches rely on the relationships between different belief states, while decision-theoretic approaches focus on the connections between beliefs and desires in shaping choices and preferences.

Epistemic approaches to belief measurement seek to explain the process by examining the interconnections between belief states. These approaches argue that belief is not a standalone entity but rather a complex system composed of multiple elements. By studying these relationships, epistemic approaches aim to provide a more comprehensive understanding of belief formation and change.

On the other hand, decision-theoretic approaches to belief measurement focus on the role of beliefs in decision-making processes. These approaches argue that beliefs play a crucial role in guiding our actions and preferences by influencing the way we evaluate different options and make choices. Decision-theoretic approaches seek to quantify the influence of beliefs on decision-making by examining the relationships between beliefs and desires.

One of the key differences between epistemic and decision-theoretic approaches is their underlying theoretical foundations. Epistemic approaches are rooted in the theory of measurement, which emphasizes the importance of establishing relationships between different quantities or properties. Decision-theoretic approaches, on the other hand, are influenced by the theory of decision-making, which focuses on the processes by which individuals make choices based on their preferences and goals.

Another important distinction between epistemic and decision-theoretic approaches is their focus on different aspects of belief. Epistemic approaches primarily concern the measurement of belief states, such as confidence or certainty. These approaches aim to quantify the strength of a person's belief in a particular proposition or hypothesis. Decision-theoretic approaches, on the other hand, also consider the role of beliefs in shaping desires and preferences. These approaches aim to quantify the influence of beliefs on the likelihood of a person pursuing a particular course of action.

Despite these differences, epistemic and decision-theoretic approaches to belief measurement share some common principles. Both approaches recognize the importance of quantifying belief and understanding the factors that influence belief formation and change. Both approaches also acknowledge the role of beliefs in shaping our decisions and behaviors.

In conclusion, beliefs can vary in intensity, and we often quantify these variations using numbers. Epistemic and decision-theoretic approaches to belief measurement offer different perspectives on the measurement of belief. Epistemic approaches focus on the relationships between belief states, while decision-theoretic approaches focus on the connections between beliefs and desires in shaping choices and preferences. Both approaches have their strengths and weaknesses, and their application depends on the specific research question and the theoretical framework employed. By understanding the foundations and principles of epistemic and decision-theoretic approaches to belief measurement, researchers can develop more accurate and nuanced measures of belief and gain a deeper understanding of the psychological processes underlying belief formation and change.

Weight: 470g
Dimension: 151 x 229 x 20 (mm)
ISBN-13: 9781009401326