Science Friday - Kahneman on ‘Noise,’ CHIPS Act, Great Salt Lake Dryness, Hybrid Toads. July 22, 2022, Part 2

Episode Date: July 22, 2022

When Times Get Tough, These Toads Make Hybrid Babies Scientists have long thought that when two animals from two different species mate, it’s a colossal error and the end of the road for the mismatched couple. It’s called interspecies breeding, and many hybrid offspring often end up sterile, such as zonkeys —a cross between a zebra and donkey. Or they can develop serious health problems, like ligers and tigons. One biologist even went as far to call interspecies breeding “the grossest blunder in sexual preference.” But is breeding across species lines always a dead end? One critter —the plains spadefoot toad—shows us that maybe it isn’t. In fact, it can give them a leg up in survival. Katherine Wu, staff writer for The Atlantic, talks with Ira about the complicated sex lives of the female plains spadefoot toads, the trade-offs females make when choosing a mate, and why hybridizing critters may not be such a biological abomination after all.     Major Semiconductor Support Bill Passes First Hurdle Earlier this week, the Senate voted in favor of the Creating Helpful Incentives to Produce Semiconductors (CHIPS) for America Act. If passed, the bill would provide more than $50 billion to companies that will build semiconductor factories here in the United States. Semiconductors are versatile materials—such as silicon—often used in electronics and in microchips. But the bulk of semiconductors, known as “chips,” are produced in other countries, mostly Taiwan. If the CHIPS Act is passed, the government will fund tech companies to build factories at home instead. Although the bill still has to go through the House and be signed by President Biden, this Senate vote is still a monumental moment in the tech world. Jesús del Alamo, a professor of electrical engineering at MIT, joins Ira to talk about why this bill is such a big deal, and what’s at stake.   Drought Could Raise Toxic Dust Around Utah’s Great Salt Lake Utah’s Great Salt Lake holds a unique ecological niche as the western hemisphere’s largest saltwater lake. The body of water is three to five times saltier than the ocean, with salinity ranging between 12 and 28 percent. According to the Great Salt Lake Institute, millions of birds from more than 250 species rely on the lake yearly, alongside a diverse variety of plants and animals. Like many bodies of water in the U.S., climate change is affecting the status quo in the Great Salt Lake. The water is drying up at an alarming rate, reaching its lowest level in recorded history this month. Now, researchers warn that toxic dust could increase as water levels continue to drop. Joining Ira to discuss the Great Salt Lake’s ecosystem and future is Bonnie Baxter, director of the Great Salt Lake Institute and biology professor at Westminster College in Salt Lake City, Utah.   A Flaw in Human Judgment: How Making Decisions Isn’t As Objective As You Think If two people are presented with the same set of facts, they will often draw different conclusions. For example, judges often dole out different sentences for the same case, which can lead to an unjust system. This unwanted variability in judgments in which we expect uniformity is what psychologist Daniel Kahneman calls “noise.” The importance of thoughtful decision-making has come in stark relief during the pandemic and in the events leading up to the January 6th insurrection. Ira talks with Nobel Prize-winning psychologist Daniel Kahneman about the role of ‘noise’ in human judgment, his long career studying cognitive biases, and how systematic decision-making can result in fewer errors. Kahneman is the co-author of “Noise: A Flaw in Human Judgment,” along with Oliver Sibony and Cass R. Sunstein, now available in paperback.   Transcripts for each segment will be available the week after the show airs on sciencefriday.com.   Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

This is Science Friday. I'm Iroflato. If two people are given the same set of facts, why do they make different decisions? Well, later in the hour, we're going to dig into some of the biggest flaws in our judgment with Nobel Prize winning psychologist Daniel Kahneman. But first, a story from the animal kingdom. When two animals from different species mate, it's thought to be a big mistake, the end of the road for those critters. It's called interspecies breeding. These hybrid offspring often end up sterile, like zonkies, across between a zebra and a donkey, or with serious health problems like ligars and tigens. But is breeding between species lines always a dead end? One critter, the plain spayed foot toad shows us, maybe not.

Here to tell us more about the strange sex lives of those toads is my guest, Catherine Wu, staff writer for the Atlantic based in New Haven, Connecticut. Catherine, welcome back to Science Friday. Hello, it's good to be here and very excited to talk frog sex. I guess we are. Before we get to that sex part, how do plain spade foot toads usually reproduce? Yeah, so it is pretty standard froggy stuff. The male plain spade foot toads will sit in some ponds and sing some songs. These ones actually sound like little ducks. They make these short quacking noises. The females mosey over and they say, wow, you sound super sexy.

They couple up. The females lay eggs and voila. They hatch into tadpoles that then grow up into more plain spadefoot toads. Yeah, that's basic eighth grade stuff. Right. So the huge asterisk that I have to put on this process that I just described is that's what happens when the ponds they're in are pretty deep. So these toads are actually living in the desert, you know, especially in parts of the southwestern U.S., maybe part of Mexico, maybe part of Canada. It's really dry there.

And sometimes the ponds that they're mating and laying their eggs into, they dry up super fast. And that actually becomes a problem. If those ponds dry up before the tadpoles become adults, they will turn into something that is very grotesquely called tadpole brittle. You'll just see this gross, crunchy peanut brittly. stuff. Hate it when that happens. Yeah, when you open that tanned and nope, this is not peanut brittle, it's tadpole brittle. That's not something any person or any mother frog wants to see. So that's bad. Basically, it is a race between the tadpole developing and the pond drying up. So when things get harsh, these female plain spatefoot toads will actually find a different species

to mate with, knowing that the hybrid offspring can actually develop faster and maybe beat the up of those ponds. So did they start listening for a different mating call? Yeah, that's exactly what they do. So it's a pretty closely related species. It's the Mexican spade foot toads, one word difference in the species name. But they do sound pretty different. Instead of making that quacking, I described earlier, these males make this kind of baritone trill, but it sounds kind of more croaky. And so the females really can tell the difference. And not only that, they'll actually pick out the Mexican spadefoot toads that will likely give them the best, fastest developing hybrid offspring. So they know which calls to listen for specifically.

Well, that's amazing. So the female plain spadefoots will listen out for the Mexican spades foot. How do they choose who to mate with? So they will actually sound a little bit different. So every call a frog makes, I guess you can sort of picture it like a word. And some frogs will call. faster. So it's like they're speaking really, really, really past, or others are speaking really slow. Others will kind of up the cadence of the trills. It's a little hard to describe because we don't have a human equivalent for it. But Fraze can distinguish all these different characteristics and figure out, oh, maybe if you're trilling faster or slower, that tells me something about your underlying genetics and how great our babies are going to be. My apologies to the toads for calling them

frogs. Actually, so I hate to break it to you, but toad is kind of a social construct. All toads are frogs, but not all frogs are toads. And even though there are technically toads out there, not all the things that we call toads are actually true toads. So it's really confusing and kind of a mess. Poof, you just blew my brain on that one. That's terrific. It sounds like these females are really weighing the consequences when they pick a mate, right? Walk me through that decision-making? Right. I mean, think about how high stakes this is. You know, they pick the wrong species and maybe all their eggs and their tadpoles end up dead before they reach maturity. That's a horrible outcome for any mother to be. Or, you know, they pick someone of the other

species, but it's someone whose hybrid babies are going to be too slow developing, kind of the same risky outcome. So they really, really, really have to be choosy. You will see these frogs, these female frogs swimming around these ponds sort of assessing, how deep is the water? How risky is it going to be if I lay eggs? And then they'll listen and say, okay, so am I picking this species or that species? And if it's this species, what kind of call am I looking for? I mean, you know, I don't want to over anthropomorphize here, but it's incredibly complicated. Like, I don't think this complex of a thought when I'm picking a mate. I don't know about you. But my calculus is not that complicated. It's their way of saying do you come here often sort of thing. Right. But also, please

answer this long list of survey questions to make sure that we're compatible. Oh, that's good because I was going to ask you. What are the tradeoffs of a female plain spade foot mating with a Mexican spade foot? I imagine they don't create a super toad, right? Right. Yeah. So, I mean, based on everything I've told you, you could sort of ask, well, why not just only mate with the Mexican spadefoot toads? It sounds great. But, you know, as you were saying at the top of the show, there are often some pretty big tradeoffs when you go between species. You know, you've had some time to diverge. Not all your genes are the same. Your eggs and sperm aren't going to be perfectly compatible. And so these hybrid babies, they develop fast, but their fertility kind of pays the price. All of the male hybrids are actually sterile. They can't have babies of their own.

And the females, they lay fewer eggs than non-hybrid females. So there is a price to pay. but, you know, the logic is better to be a little bit less fertile than entirely dead. Absolutely. I can see that on a bumper sticker. Oh, I've got that bumper sticker. I wish. Now, I imagine with climate change happening, we're going to be seeing more and more ponds drying up. What's going to happen to the breeding here? It's such an interesting question. And, you know, my rule, especially of the past two and a half years, is never predict the future. And I won't do that here. But it's such an interesting question, right?

What is going to happen to these frogs when things get dry? Hybrid babies are the way to go. Are we going to see an increase in this behavior? What is that going to mean for these species? Because even though the hybrid males are sterile, the hybrid females aren't. And these researchers have actually seen these hybrid females mating back into both parent populations. And so you see this kind of melting pot of genes. And so it's kind of cool.

You can actually see that the hybrids are really nice. funny blends of both parents. Like it'll have, you know, the pointy chin of mom and the bumpy head of dad and the, even their calls kind of sound intermediate between the two, like a trilly quack. It's kind of weird sounding. But then, you know, when the hybrids go back and mate with a purebred toad of one species or another, you can sort of see everything just blending together again. It's really fascinating. And so it's kind of interesting to think about, like how is this melding of different genetic material going to shape the evolution going forward in a world that's getting drier and hotter and just a lot more difficult for animals to navigate?

It's a pretty cool strategy, you know, when times get tough, make hybrid babies, I guess. I know you quoted the biologist who said that interspecies breeding is, quote, the grossest blunder in sexual preference. But these toads are really impressive. I mean, are scientists rethinking what they know about? about interspecies breeding? I think they definitely are. And you know what's interesting is the grossest blunder idea

was really the prevailing narrative for so long. And it's definitely not entirely wrong. I mean, think of the mules that everyone has heard about, the examples you gave at the top of the show, even the costs that these hybrid frogs are paying with their fertility. There are costs to mating outside of your species. And it is a kind of weird thing for a lot of animals to do.

And certainly if they're, their environments were an extreme, I don't think these female frogs would be doing it terribly often. But, you know, when push comes to shove, when the world is changing, I think it very clearly is a way that animals go. There are other animals that have been shown doing this, too, you know, fish and rabbits that are acquiring, you know, genes to handle pollution from other species or, you know, changing their coat colors so they can better blend in with landscapes that are less snowy now that climate change is happening. This may be a really important way for animals to continue just trying to keep up with how fast the world around them is changing. Do we have any idea how fast that's happening? What

percentage of the species might be doing this? Yeah. So this is an area of pretty active research. It's thought that at least 10% of animal species regularly, you know, make hybrid babies with another animal species. And honestly, the number is probably a lot bigger now that we have this big genetic revolution where we can go inside the genome of different animals and say, wow, that kind of doesn't belong here. You must have gotten that from this other species that, you know, you hybridized with somewhere back in your ancestry. I think that number is going to go up in the coming years. You know, this story makes me think about interspecies breeding in a different way. What was your big takeaway in researching and reporting the story? I think one thing that is really worth thinking about is,

you know, we as human beings have really put boxes around the other animals and plants and other life forms in our environment. You know, species really is kind of a human construction. And it is useful to think about, but, you know, one of the questions that is actually really challenged to answer is what is a species. Do you define it by what it can and can't mate with? Do you define it by what its genome looks like and how different that is from some species? something else is, do you define it by, you know, where it lives and the fact that it can't interact with other things very often? It's a really complicated answer. And maybe you plop an animal into an environment where it can mate with another animal and they produce functional hybrids. Are they the same species or are they just two different species that can produce functional hybrids? Really just shows us the limitations of how we sometimes oversimplify the

world around us. Absolutely. I mean, even we humans have the genes of other species in our genomes, and it has helped us survive till today. The Neanderthal and me thanks you very much, Catherine, for that interspecies chat. And I will never look at a tadpole the same way again. Yeah. Hopefully you only have non-britalized tadpoles in your future. Catherine Wu, staff writer at the Atlantic based in New Haven, Connecticut. Thank you for joining us today.

Thanks so much for having me. When we come back, a recent decision from Congress that could revitalize the U.S. tech industry, and the water level of Utah's Great Salt Lake has dropped to a record low, what that means for the lake's ecosystem and the health of the surrounding communities. Stay with us. This is Science Friday. I'm I. Ruflato. The modern computer chip, the integrated circuit, was invented by Robert Noyes way back in 1959. It was an American invention, designed and built in the good old USA. But now more than half a century later, Most of the complex computer chips in your cell phone, your laptop, your car, and even smart weapons are made abroad.

In fact, only 11% of the world's computer chips are made in America. So if you need computer chips, wait in line with the rest of the world. Recognizing the economic effects of relying on chips from abroad and the potential threat to national security, the Senate voted this week in favor of the Chips Act. That's a bill that would provide more than $50 billion to encourage companies, even foreign companies, to build semiconductor factories here in the U.S., instead of overseas. The legislation is slated to land on President Biden's desks to sign next week. It is a big deal in the tech world, and our next guest will tell us why. Joining me now is Jesus Del Alamo, Professor of Electrical Engineering at MIT.

He's based in Lincoln, Massachusetts. Welcome to Science Friday. Yes, hello. Why do we rely on other countries to build our chips? Well, most of the chip fabs today are in other countries. We have no choice. And in fact, the most advanced fabs with the most advanced technologies are all overseas. We have no choice.

If we want to deploy the most advanced products, we have to use chips that are made overseas. So even our military relies on computing chips that we don't make. Isn't this considered a national security? issue. That is a big concern, which is the reason we need to, you know, regain control of the leading edge of semiconductor manufacturing so that the most sensitive chips can definitely be made in the U.S. Let's walk through the Chips Act. How would that Act solve this problem? Well, a big chunk of the Act, $39 billion, out of the $52 billion, is really to provide incentives for semiconductor manufacturing. Essentially, this is trying to level the plane filled with what other countries are

already doing. China, Taiwan, South Korea, they are heavily helping subsidizing companies to set up shop in their countries, and the US needs to do that if we want to lure those facts to the US. And so that big chunk of the Act will go after that. But there is another 12 billion that is about thinking about future technologies, to not only regain leadership immediately, but also to be able to sustain that leadership with future technologies. What is a fab that you're talking about? Yeah, a fab is the term that we use to refer to a semiconductor manufacturing plant. This is where the chips are made. There were companies that were waiting for this Chips Act to basically pour concrete on new projects. Do we think this will move forward now? We very much hope so. It's

really critical. You know, all other significant countries, the European Union, China, Taiwan, Korea, they're offering similarly very generous incentives for American companies and other companies to set up their FAVs in their territories. So if we don't move on with this quickly, these other countries will move on and our American FAFs will set up the new FAVS overseas without any question. Do we need to build factories here if we want to stay in the tech world or to try to regain leadership in the tech world? Most definitely. So, There is a deep connection between leading-edge manufacturing and innovation. And the connection is in that the leading-edge technology, the most advanced technology,

is the most profitable also. So essentially, winner-takes-all is how this industry works. Whoever gets the most advanced technology first in the marketplace is going to rip off the greatest profits. And as a result, is going to be able to invest. into innovation at a greater level and therefore be able to move faster than competitors. So it really is critical to stay at the leading edge, to maintain the leading edge, and to just continue to play to be on the leading edge. So we can't afford not to do that.

And unfortunately, we have slipped somehow in the last few years, and we need to regain that leadership and stay there. And savvy computer chipmakers are sort of playing one country off against another, aren't they, in deciding where they would build their new factories. And I think they were waiting to see if this CHIP Act would go through, if America would be one of the competitors. Yes, it sounds perverse. But think about it. These FAB investments, they are all north of $10 billion, all those that have been announced in the last few months.

And the level of subsidies that Asian countries in particular are offering easily are in the 25 to 30%. So if you calculate 25 to 30% of $10 billion, you are really talking about a lot of money. And so it really is not surprising that companies will respond to those kinds of incentives. We need to be able to match that if we want American companies to create, and also foreign companies to create the fabs in the U.S. I think it was also interesting that there was a rare bipartisan cooperation here in Congress recognizing the weight of this issue. Yeah, and there are many aspects.

There are several aspects of these. One is you mentioned earlier the defense side of things, but there is also the jobs side of things, which is that the semiconductor industry really pays very good salaries, employs a lot of people, and there is a multiplicative effect in which each job in the semiconductor industry creates 5.7 jobs, as the semiconductor industry association estimates. So the job implications of siding semiconductor fives in the years is very significant, and so you can see how this ought to appeal across the entire political spectrum. I know there's a lot of stake here, and the tech and research industries have had their eyes on this bill for months, as I said before.

How did you feel watching it unfold this week? Were you stressed, excited, biting your nails? Yes, it has been nerve-wracking. And in fact, one of my kids has been living this with me. We've been monitoring what was happening in the Senate in the last few days, you know, with a lot of nervousness, almost minute by minute, texting each other with the latest developments. We're happy where we are right now, but there's still a lot to be done in a very short time before Congress goes into recess. So it's going to be an elviter to the last minute. Yeah, Friday, I think it's the last day before Congress goes into recess.

We'll see what happens next week. I have run out of time. I want to thank you for taking time to be with us today. Thank you very much. My pleasure. Jesus de Alamo is a professor of electrical engineering at MIT based in Lincoln, Massachusetts. Utah's Great Salt Lake has been dealing with unprecedented drought for years. This is bad news for the largest saltwater lake in the western atmosphere because the Great

Salt Lake is so, well, salty. It's home to a diverse ecosystem and many plant and animal species rely on it. Since the Great Salt Lake is shrinking so fast, some researchers are warning that toxic dust could be tossed up as things get drier. So what does this mean for the creatures that call the lake home and the communities around it? Joining me now as my guest, Dr. Bonnie Baxter, Director of the Great Salt Lake Institute and Biology Professor at Westminster College in Salt Lake City. Welcome back to Science Friday. Oh, hi. Nice to be here again. Thank you. Can you explain what makes the Great Salt Lake so special for us?

Well, so many things. I guess if we were to start with the ecosystem, it's the most important body of water on the Pacific Flyway a stopover for 10 million birds. That's a lot of birds. Wow. And those birds in the lake, they eat two invertebrates, the brine shrimp and the brine fly, which have their larval and pupil stage in the lake. And there are other invertebrates in the freshwater wetlands that feed some birds. But when you think about the lake proper, it's basically this food chain of 10 million birds eat two invertebrates. And so that's pretty cool in terms of. of the biomass that it produces. And also for the local population,

we have about 8,000 jobs on Great Salt Lake between the mineral extraction companies that make salt and soon to be lithium, and also the brine shrimp companies that harvest the insisted embryos of the shrimp that are sent around the world in aquaculture. So the lake has an economy, and you think about the lake effect on the snow,

A lot of the skiing that happens around Salt Lake City in our mountains is due to that lake effect, that it's big wet sink that the storms blow over and make what we call the greatest snow on Earth. So that's an industry that we want to protect as well. So there are a lot of ecosystem services that this lake does in addition to just being a really cool ecosystem. So the lake has been drying up for years. So is the story here that climate change has been speeding this up or? exacerbating what's going on? Yeah, I think I think the way we see it is that, you know, for about a century, we've been doing diversions from this lake. And so this is a terminal lake. And if you think about like a bathtub, it's like the puddle at the bottom of the bathtub.

And any water you take upstream doesn't make it down to the bottom. And so if we build more housing developments or we increase the amount of agriculture upstream, that those activities use water and that water never makes it down to the bottom of the watershed. And so this is one of the largest watersheds in the country. And I think that we need to be really cognizant of what water is getting to the lake and what isn't. So those diversions have happened historically for all these reasons. And that means the lake has been shrinking, but not just the lake has been shrinking. those aquifers that provide rebound on dry years are not working.

So we're in a situation now where we've set ourselves up for failure. So now we're approaching the high temperatures of climate change and the change and precipitation that we're seeing, which is less snow and more rain. And that leads to more evaporation. So that water doesn't make it where it needs to go. So the way I see it is we've been diverting. water, that has caused a crisis that allows us to not be able to rebound when we hit these pressures of climate change.

And let's talk about the potential for toxic dust, right? Yes. As the lake is drying up, you have this dust. What are research is warning that could happen? Well, many of your listeners may know the Owens Lake story that happened not so far from Great Salt Lake. Owens Lake was a body of water in California that basically was sucked dry by water thirsty L.A. And it became a dust bowl essentially and produced the highest measured PM2.5 particle pollution in the United States, the highest. That's the particle size, right? Yes. Yes. And that's the

particle size that can be really detrimental to human lung tissue. So that Owens Lake catastrophe, you know, we've done this experiment before where we've drained a body of water and let the dust fly around. That Owens Lake catastrophe, that lake is one-tenth the size of Great Salt Lake. So we're talking about a lake bed that is 10 times the size of Owen's Lake. And we're a little frightened about just the air pollution that will come from this. If you couple that with a history of mining in the Western United States, you understand that there are also heavy metals in this lake bed because a terminal lake doesn't let go of anything. It holds the memory of everything it's encountered. So metals that have come from gold smelting, for example, makes airborne mercury. We have

a methylated mercury problem in Great Salt Lake. We have selenium from mining that is also a byproduct. And then we have like a natural level of arsenic. So those things are in this lake bed, in this salt playa. And as the lake dries up, they will become airborne as well. So it's not just an air pollution dust storm, but it's a dust storm laden with heavy metals. And that is what we're frightened about. This is Science Friday from WNYC Studios. In case you're just joining us, talking to Bonnie Baxter about the drought in Utah's Great Salt Lake. So are people planning to do something about it? And what could you do about it? Well, the big secret is the lake needs water. I mean, that's really how we solve this problem. One of the ecosystem services this lake is doing

is keeping that dust at bay, you know, making the lake bed wet prevents this. So you just can't wish water to be there, can you? No, you can't. And it's really entangled in old water laws in the West, federal water laws that were developed during the Homesteading Act, really actually still govern water rights in the West. So like solving this problem, it's not just a science problem. It's a policy problem and it's a water law problem. So we all have to really think hard and work together. Luckily, the state agencies have really come to the table. The Utah legislators really came to the table this past session voted on a number of pieces of legislation that could result in getting more water into the system. So we scientists are really grateful that they're heating our warnings locally. And there's

stuff going on at the federal level as well. Such as. Well, so there's a recent bill that was introduced into both the House and Senate that would do two things. It would give some money to federal agencies to monitor saline lakes in the West, probably coming through the USGS, I think. And then the other thing it would do is explore engineering solutions to potentially get more water to the lake, which, you know, there hasn't been funding for that. So that would be pretty amazing. So are people optimistic that they're going to get something done in time to prevent this toxic dust from hurting people? Well, that's, optimism is, Depends on letting.

Yeah, right. Optimism is not a policy. I'm an optimistic person, and lately I've been extremely pessimistic because it's, I'll just mention I was there last week doing some field work with students. And I was out at Antelope Island, and Analype Island is an amazing place in itself, an island, which has an original herd of bison that were brought from the last 500 bison that were left in the West in the 1800s and placed on this island. And there's alope and coy and it's just an amazing place. So I was sampling out there.

And first of all, it isn't an island anymore. It's a peninsula because the lake has shrunk so much. I'm studying microbialites. Stramatolites, for example, are a type of microbialite. They're all dry. They're out of the water. And that is shocking. And then the ones that are still in the water, the water is getting too salty for them. So I was just there a month ago. And I see something incredibly different every time I go. So it's hard to be optimistic when I'm seeing these changes before my eyes. So it's obvious. It's obvious in real time. And that's that makes it hard. hard to be optimistic. But I do... I'm so sorry to hear about that.

Yeah. It's terrifying. And I do have hope just because there's so many people like you who are talking about the problem. And I really appreciate the attention to the lake. And I appreciate all that folks in government can do to help on these policy issues. So that gives me some optimism, just that people want to hear about the problem, you know? Yeah.

Well, we're talking about it. And we hope that something will. happen. We wish you success and good look in getting change. Thank you. Getting that water in there. Thank you so much. Dr. Bonnie Baxter, director of the great Salt Lake Institute and biology professor at Westminster College in Salt Lake City, Utah. We have to take a break and when we come back, if given the same set of information, why do people make different decisions? We'll be talking to Nobel Prize winning psychologist Daniel Kahneman about the flaws in our judgment. Stay with us. Science Friday, I'm Ira Flito. I've been thinking a lot about what drives powerful people to make,

well, how can you say it, bad decisions, decisions that seem short-sighted, or ignore key facts. The importance of thoughtful decision-making has come into stark relief during the pandemic and the events leading up to the January 6th insurrection. I was drawn to the research of Nobel Prize-winning psychologist Daniel Kahneman, who has made a career about studying decision-making. I was hoping he would help me better understand just what's going on. His most recent book, which he co-authored with Olivier C. Bonney and Cass Sunstein, is now available in paperback. It's called Noise, a flaw in human judgment. Daniel Kahneman, welcome to Science Friday. My pleasure. Nice to have you. All right, let's begin talking about this. The title of your book is

called noise. What is noise? And how is it different from bias? Well, the starting point really is that judgment is a form of measurement. We call it a measurement where the instrument is the human mind. And so the theory and the concepts of measurement are relevant. Bias in the theory of measurement is simply an average error that is not zero. That's bias. Noise in the theory of measurement is simply variability so that, you know, you could have, you could measure a line and measure it repeatedly. You're not going to get, if your ruler is fine enough, you are not going to get the same measurement twice in a row. There's going to be variability. That variability is noise. And you can see that noise is a problem for accuracy, because assume that there is no bias.

That is that the average of your measurements is precisely equal to the length of the line. still, obviously, you're making mistakes if your judgments or your measurements are scattered around the value. So that's noise and that's bias. So why do people make those mistakes? Why do we have people measuring things and then coming up with different results? Well, there are several reasons. One reason is that really people are inherently noisy so that, you know, when you sign your name for a lot of, in a row, it doesn't look exactly the same. We cannot, in fact, exactly repeat ourselves. We're in a series of states, and those states have an effect on the judgments we make.

We call that occasion noise. So, you know, a judge passing sentences is not the same in the morning and in the afternoon. The judge is not the same when in a good mood and in a bad mood. And then there are two other kinds of noise. To understand the next form of noise, the easiest to, well, let's stay with a judge. So some judges are more severe than others. Some judges are lenient. We call that level noise because the level of their judgment, there is an individual bias. But then the most interesting source of noise is that judges do not see the world in the same way. That is, if they had to rank defendants or crimes, they would not rank them alike. Some judges are really more severe with young defendants than with old defendants.

For other judges, it's the opposite. Those differences, which we call pattern noise, they're really interesting, and they are in quite a few situations. They are the main source of noise. Is that because that's where biases may influence the noise, because people have different biases that makes it noisy? That's exactly it. Noise. is really produced by the fact that there's certainly pattern noise, that people have different biases. You know, a lot of us have experienced that when we go to doctors and we get a second or a third opinion,

the doctors are looking at us conducting the same tests, and yet they come up with a different diagnosis or a different prognosis. There is a lot of noise in medicine. This is really one of the reasons we wrote that book, is that we find a lot of noise in very important systems in society. So, you know, there are easy cases. It's easy to diagnose a common call. But the moment that things get more challenging,

different physicians make different judgments. And on very difficult cases, of course, there is a lot of noise. So noise in medicine is a big problem. Speaking about that, when thinking about judgments that have a wide range of decisions, I can't help but think about the COVID-19. pandemic, how can the concept of noise help us better understand how differently world leaders decide to deal with the virus? Well, you know, it's one of the best examples of noise that we

know, that as leaders at all levels, you know, from municipalities to leaders of countries, were faced with the problems were quite similar. And they made a wide variety of different choices. That's an example of noise. And, you know, even, Each of them did it thinking that they were doing the right thing. But obviously, they couldn't all be doing the right thing if they were doing different things in the same situation. So how might leaders then be able to make better decisions and reduce noise around the very complicated decisions that need to be made about COVID? Well, you know, we have a piece of advice that is unlikely to be taken up very soon. But our advice is that in the case of COVID, it's a matter of designing how you're going to make the decision and doing it, making the decision, in a disciplined way.

When you design the process by which you will reach conclusions, then you are going to have less noise. People are more likely to reach the same conclusions if they all follow a sensible process to get to the decision. there is one source of noise that is not going to be controlled by that. And this is differences in values. So if people want different things, then they will reach different judgments. But if you're faced with an objective problem, you're trying to control the number of hospitalizations, that's a problem where the value is pretty obvious

with the systematic process of decision-making people ought to. we think would be less noisy than they were. When talking about making these decisions, what about using artificial intelligence or machine learning? There was a study that came out last year showing that the AI was better than the dermatologist in detecting melanoma. How does AI reduce noise in decision making?

AI does better than reducing noise. Any algorithm, any systematic rule that takes inputs and combines them in a specified way, will have one crucial property. It will be noise-free. You present an algorithm with the same problem twice. You're going to get the same answer. But in general, algorithms are noise-free, and it turns out this is one of their major advantages over humans.

That is, when you compare the performance of people to the performance of algorithms and rules, In many situations, the algorithm and rules are already superior to people or match people. And the main reason for the lack of accuracy of people compared to algorithm is noise. People are noisy, algorithms are not. But you'll get pushback from doctors or other people who say, you know, every patient is different. I have to treat every patient differently, and that takes a human interaction. How do you answer that?

Well, I answer that by looking at data and by comparing mistakes, the number of mistakes that are made. And it is true that humans have that tendency of viewing each case as unique. But it's also true that if you take just a few objective measures in the situation and you combine them appropriately, In many situations, an objective combination of scores is going to do better than a human judge, although the human judge has access to a lot of information and has many powerful intuitions. You know, I hear that same kind of argument about how AI is better than people. When I talk to AI people who are designing self-driving cars, they say, you know, we get a lot of pushback that the AI is not small. martyr, but if you look at the data, you'll see that a computer will drive a car better than a

person, meaning that there'll be fewer accidents. Well, all of us are biased against algorithms. And the reason we are is that when a self-driving car causes an accident, we look at that accident and we say, oh, I would have done it. A human driver would just not have made that mistake. But of course, no one asks the self-driving car about the mistakes that humans make. And the same is true in all contexts, where you measure the performance of people against the performance of algorithms. The question is overall accuracy. But the way that people look at it, mistakes that artificial intelligence makes look stupid to us. They are mistakes we wouldn't make.

And the fact that we make more mistakes overall than the AI, that's not something we respond to. One of the ideas that stuck out to me in the book was about overconfident leaders who too heavily trust their own intuition instead of weighing evidence or are too confident in a decision that's more due to chance than their own judgment. What's going on here? Well, what's going on is that most of the decision. us are overconfident most of the time. And in a way, it's a very good thing. By overconfident, what I mean is that we look at the world and we see the world in a particular way. And we feel a sense of validity. We feel that the reason we see the world as we do is because that's the way it is. What we cannot imagine is that other people looking at exactly the same situation would see it

differently because I see the truth and I respect your judgment. I expect you to see exactly the same thing that I do. Now, that's one aspect of it. Overconfidence is almost built in. But overconfidence in intuition is in a way particularly pernicious when it's not justified. Now, there are cases where intuitive expertise exists, so chess players can look at a chess situation and every move that occurs to them is going to be a strong one. But people feel they have intuitions when there is no way that they could have correct, valid intuitions. For example, anybody who makes predictions about what will happen in the stock market to individual stocks in particular is just deluding herself. It's not possible. And yet people feel that it is

possible. They have intuitions and they trust them. It's a big problem. I'm Ira Flato. This is Science Friday from WNYC Studios. If you're just joining us, I'm speaking with Nobel Prize winner Daniel Kahneman about some of the flaws in human judgment. One of the things I've been batting around a lot lately is what biases lead people to believe something that is patently false, specifically, how so many people bought into the big lie that Donald Trump really won the election and then the ensuing insurrection of January 6th. What makes people believe in an easily disputable lie so fully? Well, we have the wrong idea about where beliefs come from, our own and those about us. We think we believe in whatever we believe because we have evidence for it, because we have reasons for

believing. When you ask people, why do you believe that? They are not going to stay dumb. They're going to give you reasons, that they're convinced explain their beliefs. But actually the correct way to think about this is to reverse it. People believe in the reasons because they believe the conclusion. The conclusion comes first. And the belief in the conclusion, in many cases, is largely determined by social factors. You believe, but people that you love and trust believe. And then you find reasons for it. And they tell you reasons for believing that,

and you accept the reasons. But it's largely a social phenomenon. It's not an error of reasoning. And that, by the way, is true for your beliefs and my beliefs. Your beliefs and my beliefs reflect how we've been socialized. It reflects the company we keep. It reflects our belief in certain ways of reaching conclusions, like a belief in the scientific method. Other people just had different belief because they've been socialized differently,

and because they have different beliefs, they accept different kinds of evidence, and the evidence that we think is overwhelming just doesn't convince them of anything. Are there cases in which variability in judgment is actually a good thing? many cases. That is, we define noise, and that's important, we define noise as unwanted variability, so that when you have underwriters in an insurance company looking at the same risk, you would want them to reach approximately or exactly the same conclusions. But I want variability in the judgments of my film critics. I want variability in the judgments and opinions of people who are creating or inventing new things. So variability is often very desirable,

but in some context, variability is noxious. One last question. I've been following your career for a long time, and I've always wondered what got you and your longtime former psychologist partner, the late Amos Tversky, so interested in human biases and studying. Where did you You fellas decide this was something you wanted to study. Well, it was really ironic research. We found that we were prone to mistakes. It was all about statistical thinking when we started. And we noticed that we had wrong intuitions about many statistical problems.

We knew the solutions, and yet the wrong intuitions remained attracted. Can you put a finger on why we have so many flaws in our intentions? judgment? So it's not that you could, you know, if we could perform surgery and excise all the sources of biases from human cognition. If you removed all the sources of biases, you would remove a great deal of what makes cognition accurate in most situations. So we are built to reach conclusions, not necessarily in a logical way, but in a heuristic way.

And heuristic ways of thinking always necessarily lead to some mistake, although on average they could lead to correct judgments and faster than reason would do. It's not that we're studying incorrect mechanisms. The mechanisms are very useful. They sometimes, that mechanism, which is usually useful, will lead people to systematic errors. Well, thank you very much, Dr. Connaman, for taking time to be with us today. It's a pleasure talking with you. Daniel Connman, Nobel Prize winner, Professor Emeritus at Princeton University is the co-author of the book, Noise, a flaw in human judgment. If you want to hear more

from Daniel Connaman and how he approaches his work, go to Science Friday.com slash noise to watch a profile of him from our desktop diary video series back in 2013. If you missed any part of this program or you'd like to hear it again, subscribe to our podcasts, or ask your smart speaker to play Science Friday. I'm Ira Flato. Have a great weekend.