Leonard Jimmy Savage's theory of subjective and personal probability. Part II. Qualitative and quantitative subjective probability

This paper continues the series of publications which aims to familiarize infocommunication technology specialists with the legacy of Leonard Jimmy Savage - one of the founders of the subjective theory of probability. His fundamental work, The Foundations of Statistics, extensively covers the topics of probability, risk assessment and the expected utility theory, all of which have prominent practical applications in the present day. This second paper, corresponding to the third chapter of the source material, analyzes correlations and divergences between the objective and subjective probability theories and lays out the author’s concept of subjective probability, as well as the related notions of qualitative, quantitative and conditional subjective probability. The paper explores possible ways of determining probability values using heuristic and empirical methods, series of controlled experiments and direct measurements. Unlike objective probability, subjective probability may be applied to the research and development of virtual systems, including new types of systems that have been theorized but never realized before.