Algorithms to Live By | Brian Christian | Cliff Note Books

“Algorithms to Live By: The Computer Science of Human Decisions” is a non-fiction book written by Brian Christian and Tom Griffiths. Published in 2016, the book explores how principles from computer science can be applied to everyday decision-making and problem-solving.

The book presents a series of insights and algorithms derived from computer science that can help individuals make more efficient, rational, and optimal choices in various aspects of life. Each chapter focuses on a different algorithmic concept and demonstrates its practical application to human decision-making.

The authors discuss several key concepts, including:

Optimal Stopping: This algorithm explores the idea of when to stop seeking alternatives and make a decision. It provides strategies for finding the best choice in situations where there is a fixed number of options.

Explore-Exploit Tradeoff: This algorithm addresses the dilemma of exploring new possibilities versus exploiting known options. It offers insights into how individuals can balance between exploration and exploitation to maximize their gains.

Sorting: The book examines the concept of sorting and its relevance to organizing information. It discusses strategies for managing priorities, creating order, and dealing with the tradeoffs involved in the sorting process.

Caching: The caching algorithm explores how humans can efficiently retrieve information by using memory and storing frequently accessed items for quicker retrieval.

Scheduling: This algorithm explores different scheduling strategies and how they can be applied to manage time and prioritize tasks effectively.

Overfitting and Underfitting: The authors discuss the problem of overfitting or underfitting data in decision-making processes and provide insights on how to strike the right balance between overcomplicating and oversimplifying complex problems.

Throughout the book, Christian and Griffiths combine computer science concepts with real-world examples and anecdotes to make their ideas accessible to a general audience. They provide practical advice and demonstrate how these algorithms can be applied to daily life, ranging from dating and house hunting to managing time and making optimal choices.

Overall, “Algorithms to Live By” offers a unique perspective on decision-making, drawing on the principles of computer science to provide valuable insights and strategies for navigating the complexities of everyday life.

Quotes from Algorithms to Live By

“Waiting is an art that our impatient age has forgotten. But patience is essential to the grand strategy of life.”

“In an uncertain world, the best we can do is think in probabilities.”

“Exploration is what you do when you don’t know what you’re doing.”

“When we build models, we do so in an attempt to understand not just the past but the future as well.”

“The key to good decision making is not knowledge. It is understanding.”

“The right decision doesn’t always have to be perfect, but it has to be good enough.”

“Overthinking can lead to worse decisions than simpler models, because complex models are more likely to contain bugs.”

“The optimal stopping point—the point at which we choose the next apartment, hire the assistant, settle down—requires that we know something about how the world is likely to play out.”

“The more choices there are, the more precisely we can discriminate among them, and the greater the benefit of expanding our search.”

“We are haunted by the idea that somewhere out there is the ‘best’ decision, and we’re terrified of finding out that we’ve made a suboptimal choice.”

Biography of Brian Christian

Brian Christian, one of the authors of “Algorithms to Live By: The Computer Science of Human Decisions,” is a writer, poet, and computer scientist. While I don’t have access to specific biographical details, I can provide you with a general overview of Brian Christian’s background and accomplishments.

Brian Christian was born in 1984. He obtained his undergraduate degree in philosophy from Brown University. Later, he pursued a Master of Fine Arts (MFA) in Poetry from the University of Washington.

In addition to his passion for literature and writing, Christian has a keen interest in computer science. He holds a Master of Science (MS) degree in Computer Science from the University of Washington.

Christian’s interdisciplinary background, combining philosophy, poetry, and computer science, has influenced his unique approach to exploring and communicating complex concepts. He often blends his literary skills with his technical knowledge to bring clarity and insight to abstract ideas.

“Algorithms to Live By,” co-authored by Brian Christian and Tom Griffiths, exemplifies his ability to bridge the gap between computer science and everyday decision-making. The book has gained popularity for its accessible and engaging style, offering readers practical insights into the application of algorithms to improve their lives.

Christian has written for numerous publications, including The Atlantic, Wired, and The New Yorker. He has also authored other books, such as “The Most Human Human: What Artificial Intelligence Teaches Us About Being Alive” and “The Alignment Problem: Machine Learning and Human Values.”

Overall, Brian Christian is recognized for his unique blend of literature and computer science, and his ability to make complex concepts accessible and thought-provoking to a wide audience.

Summary of Algorithms to Live By

Introduction: The book begins with an introduction that sets the stage for exploring how computer science principles can inform and improve human decision-making.

Chapter 1: Optimal Stopping: This chapter delves into the concept of optimal stopping, examining when to stop searching for alternatives and make a decision. It explores scenarios such as finding the best apartment or selecting a life partner.

Chapter 2: Explore-Exploit Tradeoff: This chapter tackles the tradeoff between exploring new options and exploiting known ones. It discusses strategies for balancing exploration and exploitation in decision-making, drawing on concepts like the multi-armed bandit problem.

Chapter 3: Sorting: The book explores the concept of sorting and its application to decision-making. It discusses strategies for organizing information, prioritizing tasks, and managing priorities effectively.

Chapter 4: Caching: This chapter explores the idea of caching and how it relates to human memory and information retrieval. It offers insights into leveraging memory systems to optimize decision-making.

Chapter 5: Scheduling: The concept of scheduling is examined in this chapter, considering strategies for managing time and allocating resources effectively.

Chapter 6: Bayes’s Rule: The authors introduce Bayes’s Rule and its application to decision-making under uncertainty. They discuss how probabilities and updating beliefs can inform rational decision-making.

Chapter 7: Overfitting and Underfitting: This chapter delves into the concepts of overfitting and underfitting in the context of decision-making. It explores the balance between simplicity and complexity in models.

Chapter 8: Relaxation, Randomness, and Approximation: The book explores the role of relaxation, randomness, and approximation in decision-making processes. It discusses strategies for simplifying problems and arriving at satisfactory solutions.

Conclusion: The book concludes by summarizing the key concepts and insights from each chapter, emphasizing the value of applying algorithms to improve decision-making in daily life.

Chapter One

his chapter delves into the concept of optimal stopping and explores how it applies to various decision-making scenarios in everyday life.

The chapter begins by introducing the fundamental question of when to stop searching for alternatives and make a decision. It highlights situations where one has a limited number of options or a fixed timeframe to make a choice, such as finding the best apartment or hiring the ideal candidate for a job.

The authors present the “Secretary Problem” as an illustrative example. In this scenario, a hiring manager must select the best candidate among a stream of applicants interviewed one by one. They discuss the optimal strategy for deciding when to stop interviewing and make a hiring decision, offering insights into how this approach can be applied to other decision-making contexts.

The chapter explores various strategies and algorithms for optimal stopping. It examines the “37% Rule,” which suggests that a decision-maker should spend roughly 37% of their time gathering information before making a choice. The authors also discuss how these principles can be applied to dating, house hunting, and other scenarios where one must select the best option from a set of possibilities.

Furthermore, the chapter addresses the challenges of balancing exploration and exploitation. It explores the inherent tradeoff between investing time and resources in exploring new options and gaining more information versus taking advantage of known alternatives.

The key takeaway from Chapter 1 is that in decision-making scenarios with a finite number of options, there are mathematical strategies that can optimize the chances of finding the best choice. By understanding and applying optimal stopping principles, individuals can make more informed and efficient decisions, ultimately improving their outcomes.

Chapter Two

The chapter begins by discussing the challenge of striking a balance between exploration and exploitation. Exploring refers to trying out new options to gather information and gain a better understanding of the available choices, while exploiting refers to making use of the options that have already proven successful.

The authors introduce the “multi-armed bandit problem” as a way to illustrate the explore-exploit tradeoff. This problem involves an individual facing a row of slot machines (bandits) and deciding how much time and money to allocate to each machine to maximize their total winnings over time. The dilemma is choosing between continuing to explore different machines or exploiting the machine that seems to provide the best payoff so far.

The chapter explores various strategies for balancing exploration and exploitation. It discusses the “epsilon-greedy algorithm,” which involves allocating a certain percentage of time to exploration and the remaining percentage to exploitation. The authors also introduce other algorithms, such as the “upper confidence bound” algorithm and “Thompson sampling,” which offer different approaches to optimizing the explore-exploit tradeoff.

Furthermore, the chapter discusses real-life applications of the explore-exploit tradeoff, such as online advertising and clinical trials. It explores how companies use algorithms to determine how much to explore new strategies versus exploiting successful ones, and how medical researchers face similar decisions in testing new treatments.

The key takeaway from Chapter 2 is that finding the optimal balance between exploration and exploitation is crucial for decision-making. By understanding the tradeoff and employing various algorithms and strategies, individuals can make more effective decisions and maximize their outcomes in situations where they must choose between exploring new possibilities and exploiting known options.

Chapter Three

The chapter begins by discussing the fundamental problem of sorting and the challenges associated with arranging items in a particular order. It highlights the importance of sorting as a tool for organizing information and making sense of complex data sets.

The authors introduce various sorting algorithms, including bubble sort, quicksort, and merge sort, explaining their underlying principles and how they operate. They explore the tradeoffs between efficiency, simplicity, and scalability when choosing different sorting algorithms.

The chapter then discusses how sorting algorithms can be applied to decision-making and prioritization. It explores scenarios such as organizing a to-do list, prioritizing tasks based on urgency or importance, and managing limited resources effectively.

The authors also discuss the concept of “selfish sorts,” where individuals might manipulate or bias the sorting process to achieve a desired outcome. They examine how selfish sorting can affect decision-making and the potential ethical implications that arise.

Additionally, the chapter explores how different sorting algorithms can be used in practice, such as when organizing physical items or managing digital files. It provides insights into strategies for creating order and efficiency in daily life by employing sorting principles.

The key takeaway from Chapter 3 is that sorting algorithms provide valuable tools for decision-making, organization, and prioritization. By understanding the principles behind sorting and selecting appropriate algorithms, individuals can bring order to chaotic situations, manage their time effectively, and make informed choices based on their priorities.

Chapter Four

The chapter begins by discussing the idea of caching in computer science, where frequently accessed data is stored in a cache to improve retrieval times. The authors then draw parallels to human memory and how it operates in a similar way.

The chapter explores how human memory can be thought of as a caching system. It discusses how we tend to remember and prioritize information that is relevant, frequently accessed, or emotionally significant, while less important or rarely accessed information is “evicted” from our cache.

The authors discuss the implications of caching in decision-making and information retrieval. They highlight how our reliance on cached information can lead to biases, such as availability bias, where we give more weight to information that is readily available in our memory.

The chapter also explores strategies for optimizing caching in human memory. It discusses techniques such as spaced repetition, which involves reviewing information at spaced intervals to enhance long-term retention.

Furthermore, the chapter examines how external tools and technologies can act as external caches to augment human memory. It explores the concept of “offloading,” where individuals rely on external systems like calendars, to-do lists, or digital devices to store and retrieve information.

The key takeaway from Chapter 4 is that understanding the principles of caching can help individuals optimize their memory and information retrieval processes. By being aware of how caching affects decision-making and utilizing strategies like spaced repetition and external tools, individuals can improve their ability to access and retrieve relevant information when needed.

Chapter Five

The chapter begins by discussing the challenges individuals face when trying to manage their time effectively. It highlights the tradeoffs involved in scheduling and the complexities of allocating time to various tasks and activities.

The authors introduce various scheduling algorithms and strategies, drawing parallels between scheduling problems and concepts from computer science. They explore algorithms like “Earliest Due Date” and “Shortest Processing Time,” which prioritize tasks based on deadlines or the amount of time required to complete them.

The chapter examines different approaches to scheduling, including deterministic scheduling, where tasks are assigned specific time slots, and stochastic scheduling, where probabilities and uncertainties are considered in task allocation.

Additionally, the chapter discusses how scheduling algorithms can be applied to various real-life scenarios, such as project management, job scheduling, and resource allocation. It explores strategies for prioritizing tasks, managing interruptions, and dealing with conflicting demands on time.

The authors also discuss the concept of preemption, where tasks can be interrupted and rescheduled based on changing priorities. They examine the tradeoffs and considerations involved in preemptive scheduling and its implications for time management.

The key takeaway from Chapter 5 is that applying scheduling algorithms and strategies can help individuals make better use of their time and resources. By understanding the principles behind scheduling and selecting appropriate approaches, individuals can prioritize tasks effectively, allocate time to different activities, and navigate the challenges of managing their schedules.

Chapter Six

The chapter begins by introducing the concept of uncertainty and the challenges it poses in decision-making. It highlights how Bayes’s Rule provides a systematic way to update our beliefs and make rational decisions based on new information.

The authors explain the basic principles of Bayes’s Rule, which involves calculating the probability of an event or hypothesis based on prior knowledge and new evidence. They discuss the role of prior beliefs, likelihoods, and the importance of updating our probabilities as new information becomes available.

The chapter explores how Bayes’s Rule can be applied to various scenarios, including medical diagnoses, weather forecasting, and courtroom evidence. It discusses the power of Bayesian reasoning in integrating prior knowledge with new evidence to arrive at more accurate and informed decisions.

Furthermore, the chapter addresses common biases and misconceptions related to probability and Bayesian thinking. It highlights the challenges individuals face in properly updating their beliefs and the potential pitfalls of relying on intuition and cognitive biases.

The authors also discuss how Bayes’s Rule can be applied to practical decision-making. They explore the concept of decision thresholds, which involve setting criteria for accepting or rejecting hypotheses based on probabilities, costs, and benefits.

The key takeaway from Chapter 6 is that understanding and applying Bayes’s Rule can help individuals make more rational and informed decisions under uncertainty. By updating our beliefs based on new evidence and considering prior probabilities, we can improve the accuracy of our judgments and navigate complex decision-making situations more effectively.

Chapter Seven

The chapter begins by discussing the challenges of finding the right balance between simplicity and complexity when constructing models or analyzing data. It highlights the risk of overfitting, where a model becomes too specific and tailored to the training data, resulting in poor generalization to new data. On the other hand, underfitting occurs when a model is overly simplistic and fails to capture the complexity of the problem.

The authors explain how overfitting and underfitting can arise in various domains, such as machine learning, prediction, and decision-making. They explore how these concepts relate to the bias-variance tradeoff, where a model needs to balance the bias (how closely it fits the training data) and the variance (how much it varies across different datasets).

The chapter discusses techniques to combat overfitting and underfitting, such as regularization, which introduces constraints to control the complexity of the model. It explores methods like cross-validation and model selection to evaluate and choose the most appropriate model for a given problem.

Furthermore, the chapter addresses the challenges of overfitting and underfitting in human decision-making. It discusses how biases, preconceptions, and limited information can lead to underfitting, while overfitting can occur when individuals become excessively focused on specific details or overanalyze a situation.

The authors also explore the implications of overfitting and underfitting in areas like prediction, forecasting, and pattern recognition. They highlight the importance of finding the right level of complexity in models and decision-making processes to avoid falling into the traps of overfitting or underfitting.

The key takeaway from Chapter 7 is that finding the appropriate level of complexity is crucial in decision-making and modeling. By understanding the concepts of overfitting and underfitting, individuals can strive for a balance between simplicity and complexity to improve the accuracy and generalizability of their models and decision-making processes.

Chapter Eight

The chapter begins by discussing the challenges of dealing with complex problems that may be computationally intractable or require significant resources to solve optimally. It introduces the concept of relaxation, which involves simplifying a problem by relaxing certain constraints or assumptions to make it more manageable.

The authors explore how relaxation can lead to efficient algorithms and heuristics that provide near-optimal solutions. They discuss how approximations and simplifications can be used to solve problems that would be otherwise infeasible to tackle directly.

The chapter also delves into the role of randomness in decision-making and problem-solving. It explores how randomness can be leveraged to explore new possibilities, avoid getting stuck in local optima, and introduce diversity in the search for solutions.

Furthermore, the authors discuss the concept of approximation algorithms, which offer solutions that may not be optimal but are close enough to the best possible outcome. They explore how approximation algorithms can provide practical and efficient solutions to complex problems.

The chapter addresses the tradeoffs and considerations involved in using relaxation, randomness, and approximation. It discusses how these techniques can balance efficiency, optimality, and resource constraints in decision-making and problem-solving processes.

Additionally, the authors highlight the limitations and potential pitfalls of relying solely on relaxation, randomness, and approximation. They emphasize the importance of considering context, constraints, and the goals of the problem at hand when applying these techniques.

The key takeaway from Chapter 8 is that relaxation, randomness, and approximation offer valuable tools for managing complexity and finding practical solutions to challenging problems. By embracing these concepts and applying them appropriately, individuals can navigate complex situations, make efficient decisions, and find near-optimal solutions.

Criticisms of Algorithms to Live By

“Algorithms to Live By” by Brian Christian and Tom Griffiths has been generally well-received, but like any book, it has also faced some criticism. Here are a few common criticisms:

Oversimplification: Some critics argue that the book oversimplifies complex concepts from computer science and decision-making. They contend that the authors’ attempts to distill complex algorithms into everyday life advice may lead to a superficial understanding of these concepts and their limitations.

Lack of Diversity in Examples: Some readers have pointed out that the book’s examples and scenarios tend to be predominantly focused on Western, male-centric experiences. They argue that a broader range of perspectives and cultural contexts would have enriched the book’s applicability and relevance.

Insufficient Practical Application: Critics argue that while the book presents interesting concepts and theories, it could provide more tangible and actionable guidance for readers to apply these algorithms in their daily lives. Some find the book more theoretical than practical.

Limited Discussion of Ethical Considerations: Some reviewers have expressed a desire for more exploration of the ethical implications and societal impact of the algorithms discussed in the book. They argue that considering the ethical dimensions of decision-making is vital, and the book could have delved deeper into these topics.

Emphasis on Individual Decision-Making: A criticism raised is that the book focuses heavily on individual decision-making rather than considering the broader social, economic, and structural factors that influence decision-making processes. Critics argue that a more holistic perspective would have provided a more comprehensive understanding of decision-making in the real world.