What is “Weapons of Math Destruction”?

Cathy O’Neil’s Weapons of Math Destruction: How Big Data Increases Inequality and Threatens Democracy was published in 2016 as a warning of how algorithms, which she calls “Weapons of Math Destruction” (or WMDs), are threatening America’s prosperity for anyone not already rich and powerful. Her book covers her personal journey, from mathematics professor to a hedge fund “quant” to a data scientist, while explaining how she came to discover the effect of housing mortgage algorithms created the housing bubble popping in 2008, then later discovering how other algorithms were also poised to have other devastating effects. Each chapter, she expands on a different category of algorithm that are ruining or threatening equality and democracy, with studies and numbers to back each condemnation up.

What I Liked About Weapons of Math Destruction

I particularly appreciated Cathy’s forthright, direct manner of writing as she described and explained each WMD. She was succinct in describing what each algorithm was meant to do, how it attempted to approach this purpose, and what the effects of its failure meant for those it targeted. My favorite quote of hers, from page 13 of the introduction of Weapons of Math Destruction, reads

Big Data has plenty of evangelists, but I’m not one of them.

I agree that she is not a fan of Big Data. She called out the WMDs for using discriminatory proxies to decide which resumes are considered by humans, which people are targeted by for-profit colleges, and even which communities are visited most by the police. I like the questions to determine if an algorithm is a WMD or not, that she introduced in chapter 1:

“Even if the participant is aware of being modeled, or what the model is used for, is the model opaque, or even invisible?” (pg 28)
“Does the model work against the subject’s interest? In short, is it unfair? Does it damage or destroy lives?” (pg 29)
“The third question is whether a model has the capacity to grow exponentially. As a statistician would put it, can it scale?” (pgs 29-30)

My Main Complaint

Cathy O’Neil states in the subtitle she will explain “How Big Data increases inequality and threatens democracy”, but her conclusion gives little direction on how individuals can fix this issue or fight against WMDs. She gives an examples of an ethical code that data scientists can swear by, lists different regulations and laws that could force businesses to audit their algorithms, and examples of helpful predictive models. She fails to provide examples of how individuals can fight back for our democracy, though. Does she believe WMDs can only be fought by regulating corporations? Was she unaware of how to use VPNs, or remove cookies or internet history, or how to remove information from circulation? Are projects like the Web Transparency and Accountability Project at Princeton not seeking volunteers? (Note: I checked their website, and it appears the last blog post was written in 2019). I believe it would have been more helpful and uplifting for her to issue a personal call-to-action than to simply list challenges of fighting current-day WMDs.

My Overall Rating

Overall, I believe Weapons of Math Destruction is a great introduction to the ethical, legal, and political concerns caused by Big Data algorithms. The average American reader, even without a math or statistics background, could easily grasp the examples and problems that Cathy O’Neil presents for consideration. I would rate this book 4 stars for being easy to understand and a quick read, but lacking direction for what to do with the provided information. I would hope anyone wishing to use an algorithm in their business reads this book to make sure they are not creating the next Weapon of Math Destruction; they may just need to search elsewhere for direction on how to fight other WMDs.