I'm in the midst of a blog series on AI-related ideology and politics. In Part III, I considered some implications and pitfalls of the AI factions and their agendas. This part is about a specific hot-button issue: "algorithmic bias," which has some contentious race-related associations.
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| An image model's attempt to produce an infographic about AI mistakes, which happens to be mostly full of garbled text and other mistakes. Generated by @zacshaw on Twitter. |
In recent years, AI (largely of the Artificial Neural Network variety) has been gradually making inroads into various decision-making roles: assessing job applicants, screening potential homebuyers, detecting fraudulent use of social services, and even helping to diagnose medical patients. Numerous concerns [1][2][3] have been raised that these systems are biased: i.e. they are unfairly rejecting qualified people, or accepting unqualified people, on the basis of characteristics irrelevant to the decision. This is particularly worrying for a couple of reasons.
First, handing an important decision off to an AI system removes the details of how that decision was made from human supervision. Typical ANN systems are notoriously opaque. In effect, they make decisions by comparing the case under present consideration, to patterns or associations found in their training data. But they are not naturally good at supplying a logical breakdown of how a decision was reached: which features of the present case matched the training material, how they were weighted, and so on. (The "explainable AI" research field is seeking to ameliorate this.) So, say your job application or attempt to access medical treatment gets denied by an algorithm. It's possible that no one knows exactly why you were denied, and no one can be held accountable for the decision, either. The magic box pronounced you unworthy, and that's the end of it. Faulty automated systems (from an earlier era than the current crop of ANN-based tools) have even sent people to prison for non-existent crimes. [4]
Second, some people are inclined by default to trust an AI system's decision more than a human's. It's just a computer doing deterministic calculations, right? It doesn't have emotions, prejudices, ulterior motives, conflicts of interest, or any of the weaknesses that make humans biased, right? So the expectation is that all its decisions will be objective. If this expectation does not hold, members of the public could be blindsided by unfair AI decisions they did not anticipate.
And in fact, some are so convinced of these default assumptions that they insist the whole idea of algorithmic bias must be made up. "Math can't be biased." The algorithms, they say, are just acting on the facts (embodied in the training data). And if the facts say that members of one group are more likely to be qualified than another ... well, maybe a skewed output is actually fair.
Although mathematics and algorithms do, in truth, know nothing of human prejudice, algorithmic bias is quite real. Let's start by looking at an example without any especially controversial aspects. There was a rash of projects aimed at using AI to diagnose COVID-19 through automated analysis of chest X-rays and CT scans. Some of these failed in interesting ways.
"Many unwittingly used a data set that contained chest scans of children who did not have covid as their examples of what non-covid cases looked like. But as a result, the AIs learned to identify kids, not covid.
"Driggs’s group trained its own model using a data set that contained a mix of scans taken when patients were lying down and standing up. Because patients scanned while lying down were more likely to be seriously ill, the AI learned wrongly to predict serious covid risk from a person’s position.
"In yet other cases, some AIs were found to be picking up on the text font that certain hospitals used to label the scans. As a result, fonts from hospitals with more serious caseloads became predictors of covid risk." [5]
All these examples are cases of the AI mistaking a correlation (which happens to exist only in its limited training dataset) for a causative factor. Unlike experienced doctors - who know full well that things like label fonts have nothing to do with causing disease, and are thus chance associations at best - these ANI systems have no background knowledge about the world. They have no clue about the mechanisms that produced the data they're being trained upon. They're just matching patterns, and one pattern is as good as another.
Now imagine that an AI grabs onto a correlation with race or gender, instead of poses or fonts. That doesn't make the person's race or gender meaningful to the question being answered - not any more than label fonts are meaningful to an accurate determination of illness. But the AI will still use them as deciding factors.
The COVID-19 diagnosis summary also comments on another type of failure:
"A more subtle problem Driggs highlights is incorporation bias, or bias introduced at the point a data set is labeled. For example, many medical scans were labeled according to whether the radiologists who created them said they showed covid. But that embeds, or incorporates, any biases of that particular doctor into the ground truth of a data set. It would be much better to label a medical scan with the result of a PCR test rather than one doctor’s opinion, says Driggs. But there isn’t always time for statistical niceties in busy hospitals." [6]
If an ANN's training data contains examples of human decisions, and those decisions were prejudiced or otherwise flawed, the AI algorithm (despite having no human weaknesses in itself) will automatically inherit the bad behavior. It has no way to judge those prior choices as bad or good, no concept of things it should or shouldn't learn. So rather than achieving an idealized objectivity, it will mimic the previous status quo ... with less accountability, as already noted.
So. Training an AI for criminal sentencing? It's only going to be as objective as the judges whose rulings you put in the training set. Training it for job screening using a set of past resumes, hiring decisions, and performance ratings? It's going to mimic those previous hiring decisions and ratings, whether they fairly assessed who was qualified or not.
As a consequence of this effect, you can get (for example) a racially biased AI model without the end users or anyone on the development team actually being racist. All it takes is racism as a driving factor behind enough scenarios in the training data. And has racism historically been an issue? Of course. So it can be difficult to construct uncontaminated training sets from records of past decisions. Nobody really thinks an AI model can be racist in the same manner as a racist person ... but that doesn't mean it can't output decisions that treat people differently on the basis of irrelevant genetic or cultural attributes. As Gary Marcus says, "LLMs are, as I have been trying to tell you, too stupid to understand concepts like people and race; their fealty to superficial statistics drives this horrific stereotyping." [7]
Unfortunately, my current impression of efforts to fix algorithmic bias is that they aren't always addressing the real problem. Cleansing large datasets of preexisting biases or irrelevant features, and collecting more diverse data to swamp out localized correlations, is hard. Pursuing new AI architectures that are more particular about how and what they learn would be harder. Instead, a common approach is to apply some kind of correction to the output of the trained model. When Google's image labeling AI misidentified some Black people in photos as "gorillas," Google "fixed" it by not allowing it to identify anything as a gorilla. [8][9] Known biases in a model's training set can be mitigated by applying an opposite bias to the model's output. But such techniques could make matters even worse if executed poorly. [10]
OpenAI's approach with ChatGPT was to use RLHF (Reinforcement Learning with Human Feedback) to create another layer of training that filters offensive or potentially dangerous material from the output of the base model. Human workers assigned the RLHF layer "rewards" for "good" outputs or "punishments" for "bad" ones - at the cost of their own mental health, since they were charged with looking at horrific content in order to label it. [11] Clever users have still found ways to defeat the RLHF and finagle forbidden content out of the model. AI enthusiasts sometimes use a shoggoth to represent the incomprehensible "thinking" of large language models. The mask is the RLHF. [12]
Algorithmic bias, then, remains a known, but incompletely addressed, issue with the ANN/ML systems popular today.
In Part V of this series, I will start my examination of existential risks from AI.
[1] Giorno, Taylor. "Fed watchdog warns AI, machine learning may perpetuate bias in lending." The Hill. https://thehill.com/business/housing/4103358-fed-watchdog-warns-ai-machine-learning-may-perpetuate-bias-in-lending/
[2] Levi, Ryan. "AI in medicine needs to be carefully deployed to counter bias – and not entrench it." NPR. https://www.npr.org/sections/health-shots/2023/06/06/1180314219/artificial-intelligence-racial-bias-health-care
[3] Gilman, Michele. "States Increasingly Turn to Machine Learning and Algorithms to Detect Fraud." U.S. News & World Report. https://www.usnews.com/news/best-states/articles/2020-02-14/ai-algorithms-intended-to-detect-welfare-fraud-often-punish-the-poor-instead
[4] Brodkin, Jon. "Fujitsu is sorry that its software helped send innocent people to prison." Ars Technica. https://arstechnica.com/tech-policy/2024/01/fujitsu-apologizes-for-software-bugs-that-fueled-wrongful-convictions-in-uk/
[5] Heaven, Will Douglas. "Hundreds of AI tools have been built to catch covid. None of them helped." MIT Technology Review. https://www.technologyreview.com/2021/07/30/1030329/machine-learning-ai-failed-covid-hospital-diagnosis-pandemic/
[6] Heaven, "Hundreds of AI tools have been built to catch covid."
[7] Marcus, Gary. "Covert racism in LLMs." Marcus on AI (blog). https://garymarcus.substack.com/p/covert-racism-in-llms
[8] Vincent, James. "Google ‘fixed’ its racist algorithm by removing gorillas from its image-labeling tech." The Verge. https://www.theverge.com/2018/1/12/16882408/google-racist-gorillas-photo-recognition-algorithm-ai
[9] Rios, Desiree. "Google’s Photo App Still Can’t Find Gorillas. And Neither Can Apple’s." The New York Times. https://www.nytimes.com/2023/05/22/technology/ai-photo-labels-google-apple.html#:~:text=The%20Nest%20camera%2C%20which%20used,company's%20forums%20about%20other%20flaws
[10] Wachter, Sandra, Mittelstadt, Brent, and Russell, Chris. "Health Care Bias Is Dangerous. But So Are ‘Fairness’ Algorithms" Wired. https://www.wired.com/story/bias-statistics-artificial-intelligence-healthcare/
[11] Kantrowitz, Alex. "He Helped Train ChatGPT. It Traumatized Him." CMSWire. https://www.cmswire.com/digital-experience/he-helped-train-chatgpt-it-traumatized-him/
[12] Roose, Kevin. "Why an Octopus-like Creature Has Come to Symbolize the State of A.I." The New York Times. https://www.nytimes.com/2023/05/30/technology/shoggoth-meme-ai.html
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