Book Review: "Noise" by Daniel Kahneman, Olivier Sibony, and Cass Sunstein

I recently read the book Noise by Daniel Kahneman, Olivier Sibony, and Cass Sunstein. I will refer to it as the current book, because it was written after the book Thinking, Fast and Slow by Kahneman (one of the authors of the current book); I will refer to the latter book as the previous book because many concepts from the previous book are briefly reviewed in the current book, and as I reviewed the previous book in the post just before this one on this blog [LINK], I will sometimes compare some aspects of the current book to the previous book.

The current book introduces the concepts of statistical noise & statistical bias in human judgments, discusses the psychological biases that can lead to statistical biases & noise (of which statistical noise can be clearly seen even in the absence of clear information about statistical biases), demonstrates how statistical noise can lead to uncontrolled & large variations in human judgments in fields like criminal justice, medicine, forensic science, insurance claims adjustment, corporate hiring, and college admissions, explains the sorts of systematic techniques at individual & organizational levels that can be used to reduce noise in judgments, and discusses some tradeoffs that may be encountered when implementing these noise reduction strategies. The authors' discussion of many of the psychological biases that lead to statistical noise in judgments reviews concepts from the previous book, especially Systems 1 & 2.

When reading the current book, I found myself generally agreeing with the discussions of techniques to reduce noise in domains where the presence of significant statistical noise in judgments is broadly recognized as a severe problem. These techniques include aggregating predictions or evaluations that are made independently, structuring/sequencing discussions among people judging things so that their decisions don't affect each other through emergent group-based social dynamics, carefully accounting for base rates from external information when assessing various internal probabilities, and breaking up decision processes into smaller steps that are more clearly defined in their intent and in example decisions/anchors. It helped a lot that I had read the previous book first, such that even if I didn't remember every detail of every psychological bias presented in both the previous book and the current book, those things looked familiar upon reading them in the current book.

There were also a few new things that I learned from the current book. I learned about how the process of judgment feels so satisfying and infuses confidence into the person making the judgment specifically from the psychological signal of having completed the judgment, which explains why so many people who make professional judgments in many domains are so reluctant to turn their discretion over to more systematic rules or algorithms. I also learned about how simple models of human predictive judgments, when those predictive judgments are about specific outcomes, may do a better job at predicting the outcomes that are the objects of judgment than at predicting the judgments that humans would make, simply because those models lack within-person noise pervasive in human judgments.

However, my overall opinion of the current book was shaped more by the many major and minor (the latter to an appropriately lesser extent) criticisms of it. These minor and major criticisms as well as my concluding remarks will be presented in separate sections as follows after the jump; the spoiling of my concluding remarks is simply that I do not recommend this book to others.

Book Review: "Thinking, Fast and Slow" by Daniel Kahneman

I started reading the book Thinking, Fast and Slow by Daniel Kahneman in early 2024. This was initially recommended to me by a friend, and I became even more motivated to read it upon hearing positive things about it from colleagues at my previous job, as many of the subtleties described in the book are extremely relevant to the appropriate design of interviews, focus groups, and surveys of human subjects in social science research. However, because it is a long book and the middle of 2024 was made busier for me by moving back to Maryland, traveling a lot, and starting a new job (some of which I have discussed in a previous post [LINK]), I could not finish reading this book until much more recently. Because of this large gap between reading the initial 60% and remaining 40% of this book, I admit that I have since forgotten many details from the initial 60% of this book. Moreover, I started making notes to myself in this post based on that initial 60% because I assumed that I would be able to finish reading the remaining 40% soon afterwards and I would therefore remember the book as a coherent whole, but because that didn't happen, many of the notes that I have made in this post that were supposed to form the skeleton of this post now no longer make as much sense to me. For these reasons, this post may seem a bit more stilted than other book review posts in this blog and will likely seem stronger/more coherent when discussing the latter 40% of the book.

The book is a lengthy exposition of novel ideas in psychology & behavioral economics that were empirically validated by the author, most often in conjunction with his longtime academic collaborator Amos Tversky. The concluding chapter does a good job of recapitulating the main ideas of the book. Most of the book explores various facets of individual & group-based human behavior based on the idea that there are effectively 2 modes through which individuals process information, which the author refers to as Systems 1 & 2. System 1 "thinks fast", making snap judgments based on limited information, heuristics, and a bit of laziness, and is the aspect of thinking that drives most day-to-day reactions & decisionmaking, while System 2 "thinks slow", making more deliberate judgments with more of an effort to gather all relevant information but must in turn be consciously engaged and ultimately disengages from mental fatigue (in favor of System 1) if engaged for too long. The book also considers how individuals' typical behaviors when faced with outcomes that are certain competing with outcomes that have known or unknown probabilities deviate from behaviors idealized by microeconomic theories of expected utility, notably that while the commonly observed behavior choosing a certain gain with a lower value than the expected value of an uncertain gain can be explained to some degree by expected utility theory, the commonly observed behavior of choosing a gamble on losing outcomes with an expected loss of larger magnitude than a different certain loss cannot be explained by expected utility theory; this partly explains the risks that people take in business and can be explained in turn by how people in their perceptions tend to overestimate probabilities that are close to but not exactly 0 and underestimate probabilities that are close to but not exactly 1. Finally, the book partly explains notions of hedonic adaptation (the idea that one's sense of well-being is generally similar in many different good or bad medium- or long-term circumstances by adapting to those circumstances) by distinguishing how people rate pleasure or pain when experiencing those things versus in hindsight and shows how people's conceptions of their identities & well-being in the past, present, and future are intimately tied to their actual memories and their abilities to form & retain memories. These aspects of self-conception as well as perceptions of probability can also be tied to Systems 1 versus 2, as many seemingly shortsighted decisions or perceptions can be explained by System 1 making snap judgments lazily & using heuristics based on incomplete information.

Especially as I read the latter 40% of the book, I came to appreciate how many of the ideas of this book had permeated into other things that I had read & heard from others and that I had internalized into my own worldview & view of myself. Professionally, I could see how so many aspects of framing could be important when designing surveys & focus groups. Personally, I could see how especially as I have aged, I have in many cases consciously chosen to not worry too much about certain details and instead make decisions based on lazier heuristics because I didn't feel that the results of spending more mental energy making a decision based on System 2 would be worth the effort. At the same time, I have become more consciously aware of how my memories of things in my own life can be affected by the passage of time and by more recent events in my own life, and I have become more consciously aware of the deep entanglement between my perceptions of my own memories and the narratives that shape my perceptions of my own life & of the world. I thus feel more proud of maintaining detailed personal diaries where I take note (using System 2 as much as possible when considering things outside of the current moment) of how I feel about various things in the moment as well as in hindsight and carefully consider how & why my thoughts & feelings about different events in or aspects of my life have evolved over time. Moreover, I have become more aware over time of when I might be vulnerable (through System 1) to the power of suggestion or to a subconscious desire to align with groupthink, though given that it is System 1, I am not necessarily aware of these things until later (thinking about these things through System 2). Finally, especially over the last several years, I have come to see many things at a very broad conceptual/philosophical level, whether the experiences in my own life, the evolution of different aspects of human society, or the expansion of human knowledge, in terms of perdurantism [LINK from Wikipedia]; although I am not philosophically sophisticated enough to be able to think through & defend all of its implications, it intuitively makes sense to me to think about personal identities, feelings, people, and other things that can be said to exist, in terms of their existence in spacetime and not just in space at specific instants of time. Because of my philosophical inclination in this way, I was particularly pleased to see the author discuss the idea of time-integrated pleasure or pain and of looking at changing identities or overall life courses in terms of spacetime.

Although this book is not technical at the level of an academic journal article, it is fairly technical compared to most nonfiction books aimed at the general public, so I would say that it is aimed at a well-educated reader. That said, I do think that it is written with reasonable clarity for non-academic audiences. Additionally, the book covers many topics, and it is recommended to bear in mind the headings of sections that comprise groups of chapters, because otherwise, it is easy to lose track of the narrative of the book, especially because the book is long enough that I suspect that it would be impossible for most readers (even those who read books, including more technical nonfiction books, relatively quickly) to finish this book in one sitting. I would say that the concluding chapter is a nice way to reinforce the main points of the book in the reader's mind and that the details of each chapter can be treated as a reference when needed as opposed to forming a perfectly coherent narrative in the progression of chapters in the book.

It is important to remember that some aspects of this book are out of date. In some cases, that is just because this book was published in 2011 and had been written over many years before that; for example, the author gives an example of estimating the likelihood of choosing a particular major in college, but that example uses base rates that seem to be quite out-of-date. In other cases, the book is out of date because it is based on academic experimental work in psychology & behavioral economics, and other studies may find contradictory (either null or opposite) results to those presented in this book. The Wikipedia article about this book [LINK] discussed how most of the results from most of the studies discussed in one chapter (as an example) have been found to be not replicable, with the author afterwards admitting to putting too much faith in those studies and therefore falling prey to the same biases as those discussed in that chapter & elsewhere in the book. As a slightly different example, later parts of the book discuss the ideas of nudge theory and its seeming successes in public policy, but the Wikipedia article about nudge theory [LINK] has pointed out that later studies & meta-analyses have found that after correcting for publication biases in favor of positive results & against null results, nudging does not yield statistically significant (non-null) effects on human behavior; in this case, one of the primary researchers (who is named in this book as a collaborator of the author & pioneer of nudge theory) has made some counterarguments that I don't find convincing.

With these caveats in mind, I would still recommend this book to anyone interested in these ideas and with the patience to carefully consider them, though this may partly reflect my own biases in how I view issues of identity & the world. Follow the jump to see my other assorted & disjointed thoughts about this book.

Reflection: Leaving UC Davis

This week is my last week as a postdoctoral researcher at the UC Davis Institute of Transportation Studies (ITS-Davis). I am glad that I was able to transition from physics to transportation policy within the setting of academia and to particularly to so at ITS-Davis, which is renowned for having multidisciplinary transportation research & education that has included an increasing focus on issues of equity & accessibility in transportation planning. I learned so much, not just about transportation per se (which, in a professional context, was totally new to me when I started this job) but also about hiring, advising, and managing graduate students, applying for grants, managing grant-funded projects, communicating with different audiences beyond academia in many different forms, working on projects that are not just academic research ending in a peer-reviewed journal article, forming & managing relationships with stakeholders from government agencies, community-based organizations, and other organizations, and expanding my professional network on my own. This ultimately became the right time for me to leave ITS-Davis, but I will be grateful for the experiences & opportunities that I had in it and for the people that I got to work with.

Book Review: "Speak Freely" by Keith E. Whittington

I've recently read the book Speak Freely by Keith E. Whittington, but it has been sitting on my bookshelf for nearly 3 years. This is not a book that I chose for myself, nor is it one that someone to whom I'm close chose for me. Instead, this book is one that the Princeton University president Christopher L. Eisgruber chose for the then-incoming undergraduate class of 2022 as well as all other students, staff, and faculty to read. This in itself was typical; examples include the book Whistling Vivaldi by Claude Steele, which I have reviewed here, and the book Our Declaration by Danielle Allen, which I have reviewed here. Less typical for this book was the fact that the president personally ordered that physical copies be sent to every student (including graduate students, which included me at that time), staff, and faculty; it was commonly understood that the president is a personal friend of the author, who is a professor of constitutional law in Princeton University, and did this as a favor. Furthermore, there was a lot of chatter about this book in the middle of 2018 when this book was mailed to all students, staff, and faculty, just because so many people read it. In such a university with students & faculty who have very progressive (in the US context) political views, a conservative defense of unpopular free speech on university campuses, as expected, was seen as controversial. Personally, a few of my friends did read it and recommended that I not read it because it would be a waste of my time. I admit that these occurrences may have prejudiced my view of this book to some degree, but I genuinely tried to read & understand this book as fairly as possible. Follow the jump to see more.

My Time at the 2018 SHPE Convention

About 4 weeks ago, I got an email asking me to help Princeton University's School of Engineering & Applied Science (SEAS, of which my department, the Department of Electrical Engineering, is a constituent) recruit undergraduate students attending the 2018 Society of Hispanic Professional Engineers (SHPE) Convention to apply for graduate school in SEAS; that convention happened the previous weekend in Cleveland, Ohio. I first thought it was a little strange that I should get this email, given that it was somewhat short notice and especially given that I am not Hispanic nor have I done anything with SHPE in the past. However, after clarifying these details, I decided to go, because I do care about increasing representation of people from marginalized & underrepresented backgrounds in graduate education & academia, especially given my disability (as disability is just another aspect of diversity and too often leads to societal marginalization).
I had a lot of fun at the convention. I went with our SEAS diversity chair, a postdoctoral researcher in my department, and 13 undergraduate students; the former two people and I were there primarily to recruit, while the undergraduate students were there for their own benefit to meet corporate or academic recruiters and learn about (and hopefully secure) positions after graduation. It was definitely nice to see so many enthusiastic undergraduate students from all over the country coming with so many questions about graduate school, and I enjoyed getting to know those in my travel group more, such that I didn't feel left out even though I was essentially the only one among them who hadn't previously done anything with SHPE. There were some events that may have been more relevant to me that I missed due to the travel schedule, and I didn't find that many companies of interest to me when I explored the giant career fair (the focal point of the convention) on my own, but I did take solace in finding a few. Plus, it was nice to get out of Princeton and briefly explore a city that I hadn't really seen before (barring a short trip when I was very young, which I barely remember). Overall, I'm glad I went, and hope to have similar opportunities in the future.

FOLLOW-UP: Sexual Harassment, Power Dynamics, and Institutions

Last year, I wrote a post motivated by a case of sexual harassment and assault committed by a professor in my department against a student in his group. The incidents happened in the spring of last year, but the news about the incidents and the nominal punishment only came at the end of the year. Since then, there have been further developments, as described in this article (by Marcia Brown in The Daily Princetonian), so I am writing this post as a follow-up regarding the specific developments of this case and our department's response, even as my post last year was my attempt at exploring the broader issues at stake. Essentially, Princeton University had reason early this year to investigate further claims of past consensual relationships between that same professor and other direct professional dependents (students & postdoctoral associates), and suspended him for the spring semester and summer as they conducted their investigation. The university concluded the investigation with findings of guilt on his part of having engaged in at least one such consensual relationship, and as that is a violation of university rules, he was fired. Follow the jump to read more about my thoughts regarding this; as mentioned above, compared to my previous post on this subject, this post will have more of my raw emotional reaction to this whole process and to the specifics of this case rather than a more measured take on the broader issues at stake.

Sexual Harassment, Power Dynamics, and Institutions

I've been thinking (read: armchair philosophizing without necessarily going into much depth) lately a bit about the notion of individuals shaping the interactions they have with other people versus the other way around, and the related notion of how individuals shape institutions versus the other way around. This idea has stuck in my mind especially in the context of sexual harassment committed by a professor against a student in my department (for a broad overview, see this article by Alanna Vagianos in HuffPost, and for a more detailed account, see this article by Allie Spensley in The Daily Princetonian; disclaimer: I know the student but not the professor), because of the complicated way that power imbalances between faculty and students intertwine with institutional tensions at large research universities like Princeton University. Follow the jump to see more blather from me about this.