The Ten Equations that Rule the World : And How You Can Use Them Too (2020) by David Sumpter is a well written trip through ten equations that Sumpter describes as ruling the world. Sumpter is a professor of Applied Mathematics at the University of Uppsala.
The book starts by describing how the set of equations leads to being part of the TEN, a network of people who have some insight into the world. Sumpter describes this as being a bit like a member of a secret society.
The equations are described as, The Betting Equation, The Judgement Equation, The Confidence Equation, The Skill Equation, The Influencer Equation, The Market Equation, The Advertising Equation, The Reward Equation, The Learning Equation and The Universal Equation.
The Betting Equation shows how much odds can be adjusted against reality. The Judgement Equation is the basis of Bayesian statistics. The Confidence Equation comes from the Bell Curve. The Skill Equation originates with Markov Chains. The Influencer Equation shows how a network settles against certain weights with with the weight of each being the influence of each node, this is at the heart of Google's search algorithm. The Market Equation looks at how to find signal and noise in prices. The Advertising Equation looks at how things correlate and what clumps are formed by data. The Reward Equation describes how a variable reward yield can lead to chaotic but better behaviour. The Learning Equation is the start of gradient descent and hence machine learning. Finally the Universal Equation is an if then statement that describes how computer code can solve problems.
Each chapter provides thorough descriptions of each algorithm and lots of tales of the insights that can be gained from each one. Sumpter's experiences as an applied mathematician are used to great effect. There are also some branches out into philosophy and politics that are weaker than the tales of how the algorithms were developed and how they can be used.
The Ten Equations that Rule the World is a very good math popularisation that works well. Sumpter writes well, knows his subject and has created a fine book that shows some of the insight that math can yield.