107. Bringing Data to Life

58m
Talithia Williams thinks you should rigorously track your body's data. She and Steve Levitt trade birth stories and bemoan the state of STEM education.

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Runtime: 58m

Transcript

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My guest today, Tolithia Williams, is a statistician and mathematician at Harvey Mudd College and host of PBS's NOVA series.

She's won national awards both for teaching math and for communicating mathematical ideas to the general public.

There was a lot happening in our country at the time, lots of racial reconciliation happening, and I wasn't afraid to have those conversations with students in the classroom or just ask them how they were doing.

There wasn't any magic in the material. It was still statistics, it was still math, it was still the basics, but I think it was just how they felt in that space.

Welcome to People I Mostly Admire with Steve Levitt.

Calithia first came into the public eye with a TED Talk that encouraged people to track their own bodily data to empower their interactions with the medical system.

That's a powerful idea, and I'm excited to delve into that and also to get some tips on being a world-class teacher.

So back in 2015, you won something called the Henry L. Alder Award.

It's given by the Mathematical Association of America each year to the two or three most distinguished young college math teachers in the country. What in the world are you doing in the classroom?

Gosh, Steve, I think at the time, and hopefully I continue, but really making my students feel seen and heard and valued in that space.

Often in a math classroom, we don't think of it as a space where students can feel included and a part of the learning process and the journey.

I really wanted to create a math space where students felt comfortable being a part of mathematical discovery and statistical discovery, even seeing themselves represented in the examples that we did, you know, changing names to be the names of students in my classrooms or just the names of more diverse students.

What classes were you teaching? All of the intro level courses. I do an intro probability and statistics course where we learn R programming.
I was teaching linear algebra at the time.

I was also teaching a linear regression class.

So I don't completely believe you that that's all you did. Oh my gosh.
Seriously? I mean, linear algebra. is roughly the most boring class anyone could ever take.

I don't think inclusiveness is enough to get people excited. You literally didn't do anything around the material to make it jump off the page other than change names.

We did a viral YouTube video called That Makes It Invertible. That might have had a little bit to do with it.

We talked about all the ways that a matrix is invertible to the tune of what makes you beautiful. And it was a viral mathematical sensation.

You don't know you're linear.

A few more scenes, you understand how to work with. Wait, but you're telling me me you stand at the board and you write down matrices? Who wants to do that? Nobody wants to do that.
That's what I do.

Oh,

maybe that's why you haven't won the award, Steve. No, I teach from my tablet.
I usually give out skeletal notes, so notes that are half filled in. I'll write out the rest from the tablet.

I can pull up R and run some code so that students can see things in real time. I do still send students to the board.
You know, sometimes you do just have to do matrix multiplication by hand.

There's no way to get around that. But we find fun ways to do it in teams, in groups, to compete.
You know, who can solve this the fastest? Just ways to keep students engaged in the process.

You talked about bringing the real world into the classroom, some of the racial issues that were going on in the country. Is that

attached? to the statistics or the math? Or that's just you being a mentor. It had nothing to do with whether you were teaching linear algebra or statistics.
It's both. It's being a mentor.

And then a few years ago, Susan Martinosi and I revamped the Intro PropStat course so that our final project, students looked at the New York stop question and frisk data set and did a complete statistical analysis of it to see who was being stopped, at what rate, what was the cause, was contraband found, and students saw racial discrepancies statistically.

Every year we still look at that data set and it's a challenge to teach because it's very sensitive. One year I had a student who was from New York and who was represented twice in the data set.

And you have to understand this student sort of stereotypically, like imagine Steve Urkel. This was the kind of kid that we're looking at,

tall, lanky, skinny, black kid. And it's Harvey Mudd.
We're in STEM institution. Someone said, well, you know, why did the cops stop you?

And so he says, well, you know, high schools in New York are like in the city. He's like, so I'm staying after school for a math club.
We're like, yep, math club, check. You would be in the math club.

He's like, so it's my turn to go and and get snacks. And so I'm walking down the street with these bags of snacks.
And the cops stop him. And they're like, where did you steal all these snacks from?

And he's like, no, no, no. I got it from the cafeteria.
It's for the math club. And they're like, oh, oh,

now we know you stole it. Now you couldn't come up with a better lie, kid.
So he takes him to his math club and he walks in, police behind him, and everyone's like, what in the world?

And sure enough, they're like, yep, yeah, he's just bringing snacks. This is the math club meeting.
And so he talked about how, you know, his non-black peers were able to confirm his identity.

And so then we talked about what that interaction must be like. How did he feel after that? There was no apology.
It wasn't, oh, we're so sorry that we assumed the worst in you.

And the fact that even after telling them the truth, the default assumption was that was so far from the truth that we really need to follow you now because that's more than likely a lie.

It shows how little those police understand about human psychology because no criminal would ever offer the explanation that he was heading to math club.

It would be so far from the reality that they wouldn't think of it. I always bring that story up when we talk about the data because I don't want students to feel like it's so far from them.

Like one of your mud alums is in this data set that we get to look at and analyze.

And this is why it's so important that you think about your impact on society when you're looking at data, when you're taking your profession out into the world. How does it affect people?

Does it affect people disproportionately? And what are you going to do about that? You put real effort, obviously, into your teaching.

And when I came to the University of Chicago, I had never taught at all before I arrived as an assistant professor.

It was completely obvious that in economics at a research university, my career prospects depended only on my research output.

And as long as I showed up in the classroom on time and I taught something, that was all that mattered. It wouldn't be held against me.

Look, and I'm an economist and I'm highly attuned to incentives, but actually, I just had the strong intuitive sense that being a bad teacher would be extremely painful.

How excruciating would it be to stand in front of a class for 90 minutes, mumbling away, looking at my notes, proving theorems none of the students cared about?

So for purely selfish reasons, I decided that at least once I should take a shot at being a good teacher. And it helped that I was teaching a course on the economics of crime to the undergrads.

I tried to bring the real world in, just like you do. I arranged police ride-alongs and I took them to a gun range to shoot guns.
I mean, these are kids who'd never seen a gun before.

And the real highlight was that I had a friend who was a prostitute. And once a term, she would come in and she would guest lecture to my class.

My students every year uniformly agreed that her one lecture is better than any of the lectures that I gave the entire term. I bet.

It's nothing like like the award you won, but I actually, I think because of that prostitute's lecture, I got nominated for a university award and I won it.

And the problem was that then there was a lot of pressure to keep on being a good teacher.

And honestly, I have adopted the craziest strategy for never finding out whether I'm a good teacher or not, which is I literally have not looked at student evaluations for the last 25 years.

I have foregone the value of 25 years of student feedback to to protect my fragile ego from the likelihood that I'm really not that good a teacher.

So when people say that economists are rational, all you have to do is look at behavior like that and people like me and say, no, economists are incredibly irrational.

I hate looking at student evaluations. I have a group of women faculty that I send them to.

We switch and we pick out all the good ones and then we trash all the bad ones and we're like, you're just amazing. Look at these great things that people say about you.
Like, yep, I know, I'm good.

So we're right there with you. When you think back over teachers who really influenced you it was the ones who were really great or the ones who sucked

i think often mathematicians are in the teachers that suck category unfortunately you know lots of my k through 12 and higher ed colleagues don't have a good rap for being concerned about effective teaching and in some ways we pride ourselves on who we can keep out of our field and i hate that that's the other reason that i love being a person who tries to communicate mathematics in a way that broadens the participation of who's at the table and who sees themselves as a mathematician.

Wait, what do you mean when you say that we, meaning the mathematicians, pride ourselves on keeping people out of the field?

We inadvertently weed out folks who could be math majors or could just enjoy more mathematics in college because we don't focus on effective teaching.

And so we end up with students who have to teach themselves at universities because because we have teachers who, for whatever reason, maybe our tenure process, like you say, it doesn't reward good teaching.

It rewards research and grants and publications. And so then teaching ends up not getting a lot of our professors' attention.

And so then students end up not being excited about the material and they turn away from the sciences or at least from mathematics. I mean, how absurd is it?

that in our higher education system, at least at research universities, students are paying $50,000 a year in tuition to take classes from faculty who are not chosen based on any teaching skills and who have zero career incentives to teach well.

Is it surprising that the classes are awful? It's really bizarre that we've ended up in this equilibrium, don't you think? I think it's crazy.

Part of what frustrates me is how as a STEM discipline, our intro courses might be 300 people and then part two is 100 and then the third course is 50 because we know that folks aren't going to make it.

We structure our courses assuming that people aren't going to make it instead of providing the resources so that we support the 300 students who start to graduate in our subjects.

We just kick them to the humanities as though like they'll take you. Psychology will take you.
They'll graduate you with a degree. English won't let you down.
So why will engineering let me down?

Why does chemistry let me down? Why does math let me down? Why is it that we just kick students out into other fields?

I don't know if you know, but many of the greatest economists were booted out of math PhDs because they weren't good enough. And then they turned to econ and they weren't the stars in econ.

So we're grateful for some of the dregs that you pass that way.

Going back to this idea of the equilibrium in higher ed, if it were only the most elite research universities, maybe you could say, oh, it's no big deal that those don't do teaching well.

But I think there's a real trickle-down phenomenon, at least in economics. There are probably 20 U.S.
universities who consider themselves to be in the top 10 among economics programs.

Now, obviously, that's impossible, right? There can only be 10 schools in the top 10, but 20 schools think it.

So those 20 schools call themselves top 10, and so they act the way they think a top 10 school should act, making promotion decisions based almost exclusively on publications with almost no weight on teaching in those decisions.

But then there are probably 40 schools that consider themselves top 20 econ schools. And if you're a top 20 school, then you're almost a top 10 school.
So you got to behave like the top 10 schools.

So they have to do promotion based only on research. But then of course, there's 40 more schools who think they're almost top 20 schools.

And so by the time you're done, almost every university has this bizarre emphasis on research.

There's this thought that everybody now should be publishing.

When look, there's probably so much more social benefit to just teaching well than to force everybody, even the people who want to teach well, to spend so much time doing the research.

I'm curious, when you got tenure at Harvey Mudd, did your teaching help? Was that an important piece? Oh, hugely. Yeah.
Harvey Mudd is very heavily teaching focused.

So you could not get tenure at Harvey Mudd without having excellence in teaching and having great scholarship as well. That YouTube video also was a highlight.

You obviously could have done all sorts of things with your life and been successful.

I mean, even following the path of getting a math PhD and being a professor, you've still done all sorts of things.

You're a TV celebrity, author of an inspirational book about female mathematicians, you're a public speaker. Why did you become a mathematician? Oh, Steve, you sound like my mom.
I appreciate that.

So I grew up in Columbus, Georgia, and I didn't necessarily love math at an early age. I did okay in math, but I did okay in every subject.

I didn't know any black women mathematician, so I wasn't particularly drawn to the field. But in high school, I took lots of AP courses because AP was just coming out.

in the 90s when our teachers, they were learning how to teach it, you know, if I'm being honest with you. And everybody struggled in AP calculus.

It was only one class in my entire high school of around 2,000 folks or so. And we were all just trying to get through it together.

And my AP calculus teacher would always try to give us extra credit and just encourage us. And one day after class, he says, oh, Tolithia, let me talk to you.

And I'm thinking, obviously, he's graded my exam and he's about to tell me that I just need to go back to pre-calc.

And he says, Tolithia, you're really talented in math. You should think about majoring in it when you go to college.
And my first thought was, well, obviously he has not graded my exam.

But that statement stood out to me for several reasons. First, Mr.
Dorman, my calculus teacher, was this old white guy. Well, actually, he was in his mid-50s.

And the older I get, I realize he was young and spry. Steve, he was a young man.
He was a young, vibrant man. But to my 17-year-old brain, he was an old white guy.

He didn't have to affirm my mathematical ability. You know, there was no reason for him to say that.
And second, he said, not if you go to college, but when you go, you should major in math.

And it was the first time that I heard that from someone who looked so different from me in an area where I didn't think I was thriving. You know, I was not an A student.

I was probably like a B minus, you know, in his class, maybe C plus. I didn't think I was excelling enough to major in math.
And so that affirmation really planted a seed in me. You know, here's this.

old white guy who thinks I can do math. He's the first person to invite me to the mathematical table.
So look at it, come have a seat. You belong here.
I see you as a mathematician.

Now, come to find out, he said that to every student every day. He's like, hey, Steve, let me see you after class.
Jasmine, can I see you after class today? We didn't know. He told everybody.

Wait, how did you find out then? It was at our 10-year reunion. And we were like, wait a minute.
Wait, he told you

by then he'd already made his mark.

You

have spent a lot of your time and energy. trying to be a role model, trying to show young black women that there's space for them in math.

But the way you tell that story, you almost tell it like because he was white and because he was a man and because he was old, it carried a special kind of impact. Absolutely.

I tell white men this all the time because the first thing they say is, well, Tolithia, I'm just, I'm not like you. I can't motivate like you.

And I'm like, no, you are the first person that motivated me to see myself as a mathematician. Had Mr.
Dorman been an older black woman, I would have thought, well, of course you believe in me.

Like you have to say it. This had been, you know, a woman from my church.
Like, they always say, yes, you can do anything. You can be the president.

The fact that he didn't have to, it made me hear it differently.

I think you can have so much impact, even more so sometimes, when you don't necessarily identify with that person along with their race and their ethnicity.

So then you went to Spelman College and you're wearing a Spelman hat today as we talk. And that is a historically black college in Atlanta.
Is it also still an all-female college?

It is an all-women's college, yes. Why did you pick Spelman?

I knew I wanted to go to a historically black college. I also applied to Howard and Hampton.
I went to a very diverse high school.

So I just wanted to see what it would be like to be here for four years. I'm curious.
You grew up in the deep south. Deep, deep, deep, Steve.

You were a top student. Did you face challenges and discrimination because you were black or maybe because you were a woman as you went through high school? Oh, definitely.
Definitely.

It was worse for my parents who also grew up in the South and many things didn't change. So even though people were very polite, you were supposed to stay in your space.

And as soon as you went out of that space, People would try to put you back in that space. And so as a young, bright black girl, I was often often out of my space.

And sometimes people wouldn't know what to do with me in those spaces. What made you want to go to a historically black college? I went and visited.

I walked on Spelman's campus and all of a sudden I felt different. I felt like I could exhale.
I felt like this weight was lifted. Like I didn't have to do anything.
I could just be free.

It was this freedom that I didn't feel even at my high school. There was just this sense of relief and of calmness.

And I could just walk around and no one noticed me because it was just all these beautiful black women on this campus. And I didn't stand out like I stood out at my high school.

I wanted to see what that felt like to be in a place where you blend in

and

where you are the majority. I had never been in a space where I was just the majority outside of church on Sunday for two hours.
And so I wanted to experience that.

And I knew it wasn't the real world, but I want it to be my world for the next four years. I want to see what this feels like.

I have a research paper with Roland Fryer, and I've talked about it on the podcast before, so I won't go into the details.

But the gist of it is that looking at national data on math scores, it turns out that a bunch of countries that don't seem very kind or friendly to women in general, the women have great math scores in those countries relative to the men.

And the best hypothesis we could come up with was because they have sex segregated schools in those countries. And so the girls are taught math separate from the boys.
It's just a wild hypothesis.

We've never really tested it.

But I'm curious, do you feel like being at Spelman, where it was all women, that following math maybe was an easier path for you than it would have been if you had been at a school that wasn't all women?

Absolutely. I walked on that campus and I said, oh, I can do anything.
I can be a chemist. I can be a physicist.

I can be a biologist, mathematician, engineer, English major, psychology, sociology, because all of them were black women. There was nothing that was not being done by someone who looked like me.

And so all of a sudden, every subject became possible.

You know, if I failed an exam, which I did, I didn't look around and say, oh gosh, I must have failed it because I'm the only woman in here, or I must have failed it because I'm the only black person in here.

I'm like, okay, I must have failed it because I didn't study hard enough because there are other Black women around me who passed. So clearly, that's not why I failed.

It wasn't wasn't until I got out of it and I got into an environment where I was the only woman and I was the only black person. I said, oh, I'm nervous.

I don't want to ask a question because I don't know how it's going to be perceived in this space. I'm hesitant to speak up because I don't know how these folks are going to see me.

And that was when I noticed that I felt differently about the material in this new space. Maybe it's hard to say, but have you felt more

discrimination, more outsider-ness from being a woman or being black in the math community?

Probably from being black. That's an interesting

question to think about. Yeah, definitely from being black in this space.
I think women have been accepted more as a part of the mathematical sciences community before African Americans were accepted.

But you see it, if you look at the history of our organization, the founding of the American Math Society, black mathematicians were not allowed, hence the creation of the National Association of Mathematicians, NAM, which is a society for African Americans.

And so you see where these organizations, in spite of not being accepted by the general community, birthed and created organizations for themselves.

I think we do a better job with gender equity than with racial equity in our mathematical community.

But we've got ways to grow on both axes, and I'm excited for the ways that we continue to really build bridges to connect those communities.

We'll be right back with more of my conversation with mathematician Talithea Williams after this short break.

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Now, one of the things that you're known for is encouraging people to track data about their own bodies as a form of feedback on their behaviors and to empower their interactions with the medical system.

I get the sense that you're an avid data tracker of your own bodily functions. Is that right? What sorts of things have you tracked?

I started tracking my temperature data when Donald and I first got married. We'd be taking my temperature data and trying to pinpoint ovulation.
So you got pregnant or didn't get pregnant?

So I didn't get pregnant. I didn't want to like take hormones.
I didn't want to be on birth control. And so we learned the symptothermal method.

And as a statistician, the data geek in me was like, yes, I can do a 95% confidence interval around ovulation. Like, this is great.
This is statistical.

So I was excited to chart that and look for patterns and data. It just geeked me out.

And then when we did graduate and get ready to start a family, we were able to pinpoint ovulation and you could maximize your probability of pregnancy each month. And so it worked both ways for us.

So, charting temperature is what I started doing.

Now that things are much more digital, it's easy to track the stuff on your phone and just see how data changes over time. I track my heart rate whenever I work out.
I love looking at my health data.

I love seeing how it's gotten better over time or improved over time. Weight is the only thing that I'd never look at.
Like you and your evaluations, I don't look at my weight.

And your data collection, has it paid off in your interactions with the medical system?

Yes and no. In the TED Talk, I talk about bringing my data to the table with the birth of our third son.
And it wasn't well received, but this was in 2012.

And I think since then, providers have really started to embrace patient data. much more so than they were when I was bringing his data to the table.

When I was bringing his, it was just like, I know more than you. I'm the doctor here.
I have the knowledge, and I don't want to see your little charts.

Here's the decision that I'm going to make for you. And I think now it's much more of a conversation.
There's much more respect when people bring in their historical data.

Really, you can see patterns and you can see when issues arise. And so I think there's much more respect given to the patient as well.

Also, I think when you consider a patient's perspective, they're more likely to go along with your decision.

The particular example that you give in the TED Talk

is one of the most embarrassing examples that the healthcare profession has ever offered. Because what you say is they were giving you stress tests.

I should let you tell the story, but my wife has done a lot of stress tests too.

So, towards the end of a pregnancy, when they're worried about the health of the baby, they put the mother on a table and they look at the heartbeat of the baby.

And what they want to see is that the heartbeat goes up and down enough.

And so, what you report, which I literally laughed out loud, loud, is that the doctor became concerned in your stress test because for part of that 15 minutes that you're lying there, the baby's heartbeat went from 140 or whatever a normal baby's heartbeat.

Suddenly, in a mysterious way, it dropped to 70 or to 80. And it stayed there for a while and then it went back to 140.

And no baby's heart rate has ever gone from 140 down to 70.

And anyone who's ever been around a heartbeat monitor knows that there's a woman's heartbeat and there's a baby's heartbeat and the woman's heartbeat beats at 70 and the baby's beats at 140 and how could a doctor have looked at that data and been so dense to try to induce you into labor instead of saying well we obviously picked up your heartbeat let's go try this again i said the same thing steve i said it's probably just mine I'm pretty sure.

And he's like, well, we just want to be safe. I was like, well, safe.
Let's just take the test for 20 more minutes. You know, know, safe is not inducing.
Safe is collecting more data.

The reluctance to do that and the, you know, belittling of this idea. But also, I didn't walk in with like my PhD in statistics hanging up behind me.
I didn't show that.

By the way, this is my area of expertise. And so I think there was also a bit of like, who is this woman? What does she know? And the sort of threat, like, well, you'll have to sign a waiver to leave.

And I'm like, okay, where is that waiver? And how do I sign in? And how do I leave? And so all of that sort of emboldenedness, because I knew the data.

I could look at the the data and say, the baby's fine and you're about to put the baby under stress to bring him out when he's clearly not ready.

It's a real problem, I believe, that medical training has almost nothing about statistics and data. And so we have medical professionals who are just ill-equipped to deal with the modern world.

I'll tell you my own favorite personal story involving the medical profession and statistics. It happened early on in the pregnancy of one of my kids.

And it was at the point in development where you couldn't determine the gender of the baby for sure, but by looking at the ultrasound, you had a guess at it.

And so the person conducting the exam asked whether or not we wanted to know the baby's gender, you know, acknowledging that they couldn't tell us for certain. And I said, sure, yeah.

And he says, well, I think it's a boy.

And I say, okay, how certain are you, you know, in percentages that it's a boy? And he thought for a while and he said, well, I'd say it's about 50-50.

And I had to keep from bursting out laughing because obviously I didn't need his expert guess to tell me it was 50% chance of boy.

But honestly, trying to interpret him, I think what he actually meant was there was a 50-50 chance that he could tell it was a boy. And that meant that the other 50%, he had no idea.

So really what he meant was 75-25, but he had such a bad handle on statistics that he didn't know how to express it as 75-25.

Well, we waited to know the sex of the baby for all three of them. We were like, I want to wait till it comes out.
So sure enough, for the third one, we're like telling nurses we want to wait.

And so pushing and pushing and I'm looking and I'm looking. And sure enough, the baby comes out.
Oh, look, it's a boy. And I was like, I did not wait nine months for you to just tell me.

I just wanted to look down at its wiener and see it. I don't need you to, no, at this point, don't tell me what like.
So I was just like, oh, seriously, lady.

So anyway, she handed me the boy that she got to announce. My sister, Linda, when she gave birth, she had been told from the ultrasound it was a girl, and she wanted a girl so badly.

And she had all girls' clothes. And her husband was audio taping the delivery.
And you can hear as the baby comes out and they say, It's a healthy boy.

She's like, Boy, boy,

boy. That's a risk of being told ahead of time.

I used to not understand

this data on black women mortality during childbirth and post-birth. You know, when you look at this data of how black women have such a higher chance of dying post-childbirth.

What are the numbers like? I actually haven't even heard that.

I think black women are like twice as likely to die from childbirth and after effects.

Hey, listeners, Morgan here, the show's producer. Black women are actually three times more likely to die from a pregnancy-related cause than white women.

When you dig into the data, it's unfortunately just sort of linked to discrimination and racism and how they're treated, how their symptoms are treated, if they are complaining of pain or if there's bleeding, and how quick that happens or whether it happens or not.

Initially, I was like, this is just hard to believe for me as a statistician.

Like, I just can't imagine that around the country, this is just uniformly happening to one group of women over other groups of women.

And when I look back at my birth experience, I started to see it differently because in the birthroom, there was a moment where

the nurse was just, she was really impatient because I wanted a natural birth. I didn't want an epidural.
And she was just like, who are you? Lady, get an epidural. Lay down.

We're trying to monitor you. It was borderline rude, but I didn't know.
I'm in the throes of labor. We had a doula.
And so the doula's there. And then all of a sudden, the doula starts calling me Dr.

Williams, like halfway through labor. And I'm like, okay,

you know, we're going formal, you know. So she's like, Dr.
Williams, do you want to sit on a medicine ball? Okay, Dr. Williams, do you want to walk around? All right, Dr.

Williams, do you want me to rub your back? And then all of a sudden, the nurses were like, oh, how can we make this a better pregnancy? What do you want to do?

And it was just like night and day, Steve, like the treatment from before.

to once it was like, oh, she's a doctor. She's not crazy.
She really doesn't want an epidural. She really wants to just have a natural childbirth.

And it just made me think, well, how do people get treated when they aren't Dr. Williams and when they don't have a degree to bring to the table?

Why aren't they treated the same way with regards to their birth experience? Well, you had a smart doula, I'll tell you that. Yeah.
It was only in hindsight. I was like, why did you start doing that?

That was weird. She was like, I noticed how they were treating you.
They were just being very rude to you. So you did a natural birth the first time.
Oh, all three.

Well, I was going to say, after you did it the first time, I'm kind of surprised you went back for number two and number three.

I said, if I could suffer for five years and get a PhD, how hard can pushing a baby out be? That's what I told myself. I see.
But hey, ladies, however those babies come out, it's all good.

Yeah, because in the birthing community, there's a certain kind of pressure towards natural childbirth.

And I've always felt, can you imagine if instead of the female birthing community pushing you towards a natural birth, imagine if white male doctors said, yeah, we just think women should do natural birth.

Can you imagine the outrage? How angry people would be. How can a white man be telling me that I should have a natural birth?

This is the most painful and dramatic thing in life, and it's being minimized by the white males.

But then when the pressure comes from within the community, I know my wife felt a lot of pressure to do natural childbirth and she did it and she did it all three times.

And actually the third time she did it was really one of of the most impressive things I've ever seen in my life.

When she went into labor, it was the middle of the night and she was in tremendous pain and very expressive about it. And I just had this feeling like the baby was going to come out any second.

And so I rushed to the hospital probably way too early. And they didn't even want to keep us at the hospital, but we begged them to keep us.
And so they kept us.

And so then what happened is somehow my wife went from being very expressive about her pain to going into what I can only describe as something like a meditative state.

For the next five or six hours, she sat there completely silent, did not move, did not open her eyes, did not say a word.

And when the nurse would come in and ask her periodically, how would you rate your pain on a scale of 10? She would say 10 out of 10.

Okay, but she outwardly was not even, you couldn't tell when she was having a contraction or not.

The only way you could tell she was having a contraction was by looking at the screen where you could see the monograph.

And so everyone, the doctor, the nurses, myself, we all thought that she was not progressing towards having the baby.

And we couldn't understand why she was saying 10 out of 10. So eventually, just to humor us, they measured how dilated she became.
And she was like nine centimeters down.

She was like completely dilated. Okay.
And suddenly everybody's like, what's going on? She might really be 10 10 out of 10 pain. And so they've got her in position now to actually deliver the baby.

And like, you can literally, I'm watching and you can see the head of the baby. And she opens her eyes and she says, I would like an epidural.

And we're like, what are you talking about? The baby is going to come out in like 15 seconds. She said, I need an epidural.
And we're like, she

closed her eyes and the baby was out in a minute. And I asked her afterwards, I said, like, where were you?

And she said, I just had this mantra in my head. Each contraction, I could go through it twice.
It was just totally made up words and stuff. And she said, I just did that for the six hours.

And it was weird. I'd felt the pain, but it was like someone else's pain.
It was like nothing I've ever seen in my life.

I've never been prouder about anything anyone has ever done in my life than that she did that in that way. It was crazy.
It's a beautiful, empowering experience.

And I don't think we talk about it enough. I felt the same way.

Our doula coached me through it, like relaxing during the contraction instead of tensing up, which a lot of women do and letting the contraction work for you, but also just being present and centered in the midst of the pressure because your body is like literally opening up.

I remember when, you know, the head started to come forth and she said, you're going to feel this ring of fire. And I was like, what do you mean?

And that was the moment that I, when you said that, I was like, yep, I know. That was the moment I was like, give me an epidural right now.
But it was so amazing.

And then as soon as the baby comes out, the pain is over. And then I remember standing up, like, okay, let's walk to the room.
And the nurses were just like, oh my gosh, what are you doing?

We got a wheelchair for you. I'm like, I don't need a wheelchair.
I'm fine. My legs work.
I can walk. Give me my baby.
I'm going to carry this baby.

And they were like, you are not going to carry the baby and you are not going to walk. But, you know, I hadn't had an epidural.
So I was ready to go run a marathon.

It's such an amazing experience to feel it because it's i wouldn't say painful it's pressure it's experiencing your body open up and just do this magical thing you're co-creating and you're like witnessing your body bring forth this human being and it's just amazing to be present and to feel all of it even the parts of it that don't feel as good but you get through it millennium of women before us have gotten through it and i felt like you know what i can get through it too

you're listening to people I Mostly Admire with Steve Levitt and his conversation with Talithia Williams.

After this short break, they'll return to talk about the statistics course that shaped the trajectory of Talithia's career.

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As you may remember from a past episode with mathematician Stephen Strogatz, I've been working hard to try to launch a math appreciation course, a class that's not focused on teaching kids particular computational methods, but rather aims to show them that math is powerful and interesting and surprising and relevant.

Talithia is a great teacher of mathematics, and I'm wondering whether she might have any reservations about our plans to try to change the way math is taught.

I want to go back to something we talked about at the beginning.

As I listened to you describe the path that led you to a career in math and statistics, I was struck by the pragmatism behind your choices. You know, you said, oh, the teacher said I could do it.

And I think there's implied that you felt like this was a stable job path. But there's nothing, at least in your retelling, that captured a sense of wonder or joy or passion towards math.

That's there. Well, I know you have it now.
Did the 17-year-old version of you have it? Or did you find it somewhere along the way? No, the 17-year-old did not have it.

And I didn't have it at Spelman either. By the time I got to my senior year as a math major and a physics minor, I didn't know what to do.
And Dr.

Etta Faulkner said, you should think about grad school. And I was like, grad school, like this diploma is going to take me everywhere I need to go.

I am happy to get this bachelor's degree and get on with the rest of my life. And then she showed me a chart of income at various educational levels.

And I was like, put me in this last category, whatever this PhD thing is. That's what I want.
And so that is what got me into grad school.

I started a PhD program in theoretical math at Howard University. And it was at Howard that I took my first statistics course.
It was a biostats elective in the biology department.

So this was just going to be like an easy elective to complement some of the topology and algebra and analysis that I was taking in the math department. And that was when I fell in love with data.

I fell in love with statistics. I remember we were looking at a data set of mothers, some of whom smoked during their pregnancy.
So this was just observational data.

And in it, it had the baby's birth weight, it had gestation, mother's information, age, ethnicity, and whether or not the mom smoked during pregnancy.

And I remember thinking, why are we looking at this data? Everybody knows you shouldn't smoke when you're pregnant. And everybody knows it's no good for your baby.
So sure enough.

We did a linear regression and you saw for moms who smoked, they had shorter gestation, so shorter time in the womb.

Babies were born earlier with lower birth weight, lung complications than compared to mothers who did not smoke during pregnancy. And I just remember thinking, this was a waste of time.

And then the professor says, well, the tobacco industry fought this data in court. And I perked up.
I was like, what do you mean? Fought the data. There's nothing to fight.
Look at the data.

It's obvious. You know, the only difference in these two groups of women are who smoked and who didn't.
And they said, well, it wasn't an experiment. It was an observational study.

And there could be genetic issues. Like, we don't know that it's actually nicotine.

And I remember just getting furious the more that he talked about how they tried to refute this observational evidence that was presented.

And of course, statisticians came on the defense to say, no, actually, this is legit. You know, we can't take 100 pregnant women and say, you 50 smoke, you don't.

And then we're going to see what happens, right? You can't design an experiment that's going to cause harm. And so, of course, as you know, now every cigarette packet has this warning label on it.

But that was the moment moment that I said, I want to figure out how people try to get over with data. How do they try to lie with this information?

Because here was this result that then changed how we perceived smoking and pregnancy based on this data. And yet there were folks who tried to pull the wool over our eyes.

So that's what made me transfer to Rice University to finish the PhD in statistics because of that biostats elective that I took at Howard, who knew that it was going to be the thing that would ultimately change my trajectory.

That's great. You know, I had the mathematician Steve Strogatz on the podcast.
You know, Steve. Oh, Steve is so amazing.

And listening to the contrast between the teenage version of you and the current version of you, which brings such passion and joy and wonder around math and stats, it brings me back to a radical policy recommendation that Steve Strogatz made on the podcast.

So he believes we should completely reshape high school math to de-emphasize drowning kids with an endless series of techniques and tools for solving problems they'll never ever see again in their lives and instead emphasize the wonder and the joy and the power of mathematics.

His view and my view, and it sounds like your view too, is that, look, you can always learn the specific math technique you need when you need it, but everybody shuts down.

Everyone decides along the way, look, I'm not a math person, and then you've lost them. I listened to it and I loved it.
And I was going to co-sign and see if I could partner with you guys on it.

Awesome.

The one pushback to Steve's idea, which I think is great, how do you design a course that will really just teach the beauty and just the overview of math as a discipline, just like we do music appreciation and art appreciation?

What does math appreciation look like? I would worry how we would then put students into categories because I would worry that we would end up with a tiered system

where we would have maybe students of color, low-income students who are going on a certain track that doesn't set them up to then do STEM disciplines when they go to college because they've taken this track that maybe piqued their interest.

You've taken this and, oh, now I think I want to do engineering.

And they're like, oh, if you're not doing calculus for a semester, you can't be an engineer, which is really how unfortunately a lot of our universities and colleges are set up.

And so I'd want everyone to be able to graduate so that when they got to college, they could still pursue whatever major that they'd like to.

And then you made such a great point about the calculus students also need to take a math appreciation, right? You need to know the history of math. You need to understand that.

You know, part of my book, Power in Numbers, The Rebel Women of Mathematics, was really to highlight that women have also contributed.

Because when I came through math, I didn't learn about the women who'd come before me and the great work that they had done and also the ways that they struggled to get recognition or to get the PhD that they so rightfully earned.

And so really appreciating the folks who've come before us and learning about them, I think also draws us and can attract us to the field and help us to appreciate it even more.

Yeah, because I mean, my own view is that maybe math appreciation shouldn't even be a course.

It should just be an attitude. It should be from K through 12.
It should be baked in. Exactly.

And I also feel like we spent so much time in high school on math that was relevant in the 1960s 1960s to people like Catherine Johnson, who you write about in your book, that isn't very relevant anymore.

So there's plenty of time to help kids appreciate stuff. I'm like you, I'm deeply suspicious of anything that involves tracking.

I like the idea of kids choosing from a menu of equally interesting, important things.

So I like the idea that in high school, a kid might be able to choose between statistics, data science, or calculus.

In a world in which choosing data science or statistics won't rule out your future, the only people who've really been negative towards Steve Strogat's idea in an absolute avalanche of enthusiasm that we have received from regular people, from funders, from states saying, hey, how can we implement this right away?

The only people who are not very happy about it are the professional mathematicians. They have this fear that if everybody doesn't learn all this math, somehow we're lost.

But I really think the mistake in that thinking is why do you have to learn it in high school? I didn't take any economics in high school. I didn't know anything about economics.

I started in economics. I liked it.
I majored in it. I got a PhD.

I mean, if you hadn't had the AP course at your high school, And you had showed up as Spelman, would it not have been possible if you were just super excited, passionate about math, that you could have taken entry-level calculus and still ended up as a math major?

Absolutely. I took calculus again, even though I'd taken AP calculus.
And so I started in that class and there were math majors who started in pre-calculus. Steve, I think it's a phenomenal idea.

And I really think that high school students need to learn financial math. What does it mean to have a mortgage and a car payment and interest? What are interest rates? How do you calculate that?

How do you pay down on that? There's so many real life things that they have to deal with that they just have no idea. And they just get taken advantage of as soon as they hit 21 and 22.

And they take out loans for things that they don't understand the magnitude of and end up making minimum payments.

And so I think there's just so many ways that we can better educate high school students to really be conscientious citizens and that we don't. We teach them.
math that many of them may not ever use.

May not? What do you mean may not? I was trying to be generous. I am a part of the community, Steve.
I got to go back to them now. I want him to take me back in, but take data science.

Take a stats course and understand when election season comes and you see all these polls, what does that really mean?

When COVID-19 happened, I fear that many citizens in our country and around the world were just so confused at the way that the science was being presented to them because they just didn't really have a grasp on how to understand the data and the numbers.

I mean, you and I have both been big proponents of trying to integrate data science into the math curriculum.

And that movement movement has, I think, much in common with Steve Strogat's math appreciation angle.

The idea for me of data science is if you give young people some tools for analyzing data, then they can take those tools and actually answer a question they care about.

And then it changes their life. But boy, is it hard? I mean, we know from the data science movement, we're part of how hard it is to change the system.

But still, it's one of those things where I'm pretty selfish, but it's still, this seems so important that I'm willing to put effort into it, even though it's painful and it's slow.

It's just the right thing to do. It is.
It's hard work, but it's hard work that's worth doing.

And I think if we look at maybe not our children's generation, but hopefully our grandchildren's generation, you know, maybe things will be better in that time and we'll see some of the fruit of the labor that we're putting in today.

You've had a taste of so many things professionally. What have you enjoyed the most? I really enjoyed doing Zero to Infinity, which was the most recent PBS show that came out this past November.

I think because it was

really a chance to go deep into the math and I really got to shape the direction of the show and who to talk to and what to talk about and

to highlight some of the beauty that we talk about in math, but really in a fun and exciting way to communicate these concepts that may seem really mundane, like zero, where'd that come from?

And infinity, which is this pie in the sky concept, but make it relatable to the average person. It was like a full circle moment hosting Nova Wonders.
That was great.

That was really like, what are these big questions and big ideas in science, which I think are just beautiful to bring everybody to the table. And how do we solve these big questions?

And how do we all work together? But yeah, zero to infinity was really just, let's take a step back and look at some of these basic mathematical assumptions that we just take for granted.

And where did they come from? And how can we better understand them intuitively?

And how do we communicate that to the public in a way that can be really exciting, which I'll admit, initially I didn't think was possible. Where they were like, hey, let's do zero to infinity.

I was like, oh, I can think of so many more exciting things than zero and infinity. If you had your way.
over the next 10 or 20 years.

Do you think you'll be teaching at Harvey Mudd doing the same stuff? Or do you have a different plan in mind? I love being here.

I think there's so many things that we can do and so many ways that we can contribute to the world around us.

And as I start to put my foot out into these other areas, it makes me want to take advantage of many of those spaces while we have time.

What I am realizing is that I am able to have impact outside of just my classroom in these other things that I really enjoy.

When When you step into this space where you can see the impact that you have on the lives of people, it does make me want to figure out how can I do more?

How can I have impact beyond the 32 students that come to me to learn stats, which right now, my goodness, you could watch a YouTube class on it and learn it just as well.

Like there's nothing super uber special that I bring it to the classroom. Sure, you can flatter me.
You got this great award.

But in some ways, I think some of the work that I've been doing has just touched the lives of so many more people that I would never see in my classroom.

And I'd love to find ways to continue to do that work. Well, my prediction, you will.
You have a special talent. You have a special way about you.

You have charm and a way of communicating that is really unusual. And I can only see doors opening.
Thanks, Steve. Oh, I'm tearing up over here.

If you're interested in more from Talithea Williams, check out her book. It's called Power in Numbers, The Rebel Women of Mathematics.

Her popular TED Talk is entitled Own Your Body's Data, and her most recent NOVA series is Zero to Infinity.

So now it's time for our listener question. And as always, I invite Morgan on with me to help us out.

Hi, Steve. Hi, Morgan.
So a listener named Sierra wrote with a question about the decline in global birth rates. China's population is shrinking for the first time in decades.

Europe's population is getting older. And Sierra doesn't understand why this is so concerning.
Can you explain it?

Yeah, so the reason that some people are quite worried about this is that the elderly are a dependent population. They don't work.
Someone has to support them.

And if the ratio of elderly to working age population gets higher, that means you have to take a bigger chunk of the income earned by the workers and reallocate it to the elderly, and that can cause political problems and it can make the working age people angry.

That's the first order concern that people have. There's also a second order concern, which is there's this view that only young people are creative.

And if you don't have a lot of young people around, there won't be anybody to have new ideas, good ideas, and that will lead culture, society, innovation to stagnate.

So, do you agree with that?

Not really. I don't actually think those are very good arguments.
So, like other people do. The Economist magazine just had a big article full of concern that this is an enormous problem.

But honestly, I don't think it's that big a problem. Now, certainly, the facts are true.
The population is getting older. There'll be more people who are dependent.

All of the arguments I made above are true. But why am I not that concerned about it? First, this is a problem that unfolds very slowly.

It's not like you wake up one day and suddenly the population's old. Everybody just gets a little older year by year.
So you have a lot of time to deal with it.

There's plenty of opportunities to adjust. And in general, when you have time to make adjustments, problems are not nearly as pressing as when they happen all at once.

The second reason I'm not that concerned about it is that The way people frame it does at least slightly overstate the problem, because at the same time that we have more old people, if we're having fewer children, children are also a dependent population.

The government has massive subsidies of children in the forms of public education. And so that does offset, to an extent, the aging of the population.

A third reason I'm just not that concerned about it is that there's a really simple solution. The elderly are much healthier than they used to be.
They're living much longer.

And in any sensible society, the obvious thing to do would be to raise the retirement age and raise it a lot. The retirement age, maybe it should be 70 or 75.

Now, I understand that politically, that's extremely difficult, at least today. Look at what happened in France when they tried to raise the retirement age by a few years.

On the other hand, over time, since we have 20, 30, 40 years to respond to this problem, maybe the political climate will change so it's easier to change the retirement age.

The other thing is, I don't completely buy the argument about the young people being the only creative force. It is true, young people are innovative and have more ideas.

But if you look at some of the the data about entrepreneurship, for instance, older entrepreneurs have much greater success in starting companies than do young entrepreneurs.

To me, the whole thing seems fabricated, to be honest. Although smart people disagree with me.

So in that same email, the listener, Sierra, raised another point that many people believe a society can't survive without GDP growth. Do you also believe that to be a myth?

That's a great question, a hard question. So So GDP growth is definitely not necessary for a society to survive.

But my own inkling is that it's pretty good, that it's really helpful in society if people are getting richer. I also think it depends a little bit on the culture.

I think in the USA especially, there's this sense that things should get better over time, that kids should be richer than their parents.

And even though it hasn't been true, we had Raj Chetty, an economist on the show, and his research really shows that hasn't been true in the US for a long time.

But there's this perception that's the right way for things to be. Living in Germany for a year, it feels very different.

I think there's a much greater acceptance among Germans to the idea that it's pretty good. If you can just live the life your parents lived, then that's okay.
That's not a bad thing.

To be honest, though, this is not really my area of expertise, but I'm excited because in our next episode, I'm having as a guest one of my all-time heroes and idols in economics, Robert Solow.

He really founded the study of economic growth. And I'm really excited to ask him that exact question because I really don't know what his answer is going to be.

Our episode with Robert Solow will be publishing on June 23rd. Sarah, thanks so much for writing in.
If you have a question for us, our email is pima at freakinomics.com.

That's p-im-m-a at freakinomics.com. Also, if you have a follow-up question for Talithia Williams, please send it our way.
We read every email that's sent and we look forward to reading yours.

People I mostly admire is part of the Freakonomics Radio Network, which also includes Freakonomics Radio, No Stupid Questions, and the Economics of Everyday Things.

All our shows are produced by Stitcher and Renbud Radio. This episode was produced by Morgan Levy and mixed by Jasmine Klinger.
Lyric Bautich is our production associate.

Our theme music was composed by Luis Guerra. To listen ad-free, subscribe to Stitcher Premium.
We can be reached at Pima at Frigonomics.com. That's P-I-M-A at Frigonomics.com.
Thanks for listening.

My husband, who was not my husband at the time, he had this awkward math. pickup line, which was, I wish I was your derivative, because then I'd be tangent to your curves.

No, you gotta be talking. But yeah, that literally was his pickup line.
That was it. I mean, and I was like, honey, you had me at derivative.
Really?

That was all you had to say.

The Freakonomics Radio Network, the hidden side of everything.

Stitcher.

Welcome back to Listen to Your Heart. I'm Jerry.
And I'm Jerry's Heart. Today's topic, Repatha, Evolokimab.
Heart, why'd you pick this one?

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To help know if we're at risk, we should be getting our LDLC, our bad cholesterol, checked, and talking to our doctor. I'm listening.

And if it's still too high, Repatha can be added to a statin to lower our LDLC and our heart attack risk. Hmm.
Guess it's time to ask about Rapatha. Do not take Repatha if you're allergic to it.

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