With the rise of Big Data, methods used to study the movement of stars or atoms can now reveal the movement of people. This could have important implications for cities.
- A treasure trove of mobility data from devices like smartphones has allowed the field of "city science" to blossom.
- I recently was part of team that compared mobility patterns in Brazilian and American cities.
- We found that, in many cities, low-income and high-income residents rarely travel to the same geographic locations. Such segregation has major implications for urban design.
Almost 55 percent of the world's seven billion people live in cities. And unless the COVID-19 pandemic puts a serious — and I do mean serious — dent in long-term trends, the urban fraction will climb almost to 70 percent by midcentury. Given that our project of civilization is staring down a climate crisis, the massive population shift to urban areas is something that could really use some "sciencing."
Is urbanization going to make things worse? Will it make things better? Will it lead to more human thriving or more grinding poverty and inequality? These questions need answers, and a science of cities, if there was such a thing, could provide answers.
Good news. There already is one!
The science of cities
With the rise of Big Data (for better or worse), scientists from a range of disciplines are getting an unprecedented view into the beating heart of cities and their dynamics. Of course, really smart people have been studying cities scientifically for a long time. But Big Data methods have accelerated what's possible to warp speed. As "exhibit A" for the rise of a new era of city science, let me introduce you to the field of "human mobility" and a new study just published by a team I was on.
Credit: nonnie192 / 405009778 via Adobe Stock
Human mobility is a field that's been amped up by all those location-enabled devices we carry around and the large-scale datasets of our activities, such as credit card purchases, taxi rides, and mobile phone usage. These days, all of us are leaving digital breadcrumbs of our everyday activities, particularly our movements around towns and cities. Using anonymized versions of these datasets (no names please), scientists can look for patterns in how large collections of people engage in daily travel and how these movements correlate with key social factors like income, health, and education.
There have been many studies like this in the recent past. For example, researchers looking at mobility patterns in Louisville, Kentucky found that low-income residents tended to travel further on average than affluent ones. Another study found that mobility patterns across different socioeconomic classes exhibit very similar characteristics in Boston and Singapore. And an analysis of mobility in Bogota, Colombia found that the most mobile population was neither the poorest nor the wealthiest citizens but the upper-middle class.
These were all excellent studies, but it was hard to make general conclusions from them. They seemed to point in different directions. The team I was part of wanted to get a broader, comparative view of human mobility and income. Through a partnership with Google, we were able to compare data from two countries — Brazil and the United States — of relatively equal populations but at different points on the "development spectrum." By comparing mobility patterns both within and between the two countries, we hoped to gain a better understanding of how people at different income levels moved around each day.
Mobility in Brazil vs. United States
Socioeconomic mobility "heatmaps" for selected cities in the U.S. and Brazil. The colors represent destination based on income level. Red depicts destinations traveled by low-income residents, while blue depicts destinations traveled by high-income residents. Overlapping areas are colored purple.Credit: Hugo Barbosa et al., Scientific Reports, 2021.
The results were remarkable. In a figure from our paper (shown above), it's clear that we found two distinct kinds of relationship between income and mobility in cities.
The first was a relatively sharp distinction between where people in lower and higher income brackets traveled each day. For example, in my hometown of Rochester, New York or Detroit, the places visited by the two income groups (e.g., job sites, shopping centers, doctors' offices) were relatively partitioned. In other words, people from low-income and high-income neighborhoods were not mixing very much, meaning they weren't spending time in the same geographical locations. In addition, lower income groups traveled to the city center more often, while upper income groups traveled around the outer suburbs.
The second kind of relationship was exemplified by cities like Boston and Atlanta, which didn't show this kind of partitioning. There was a much higher degree of mixing in terms of travel each day, indicating that income was less of a factor for determining where people lived or traveled.
In Brazil, however, all the cities showed the kind of income-based segregation seen in U.S. cities like Rochester and Detroit. There was a clear separation of regions visited with practically no overlap. And unlike the U.S., visits by the wealthy were strongly concentrated in the city centers, while the poor largely traversed the periphery.
Data-driven urban design
Our results have straightforward implications for city design. As we wrote in the paper, "To the extent that it is undesirable to have cities with residents whose ability to navigate and access resources is dependent on their socioeconomic status, public policy measures to mitigate this phenomenon are the need of the hour." That means we need better housing and public transportation policies.
But while our study shows there are clear links between income disparity and mobility patterns, it also shows something else important. As an astrophysicist who spent decades applying quantitative methods to stars and planets, I am amazed at how deep we can now dive into understanding cities using similar methods. We have truly entered a new era in the study of cities and all human systems. Hopefully, we'll use this new power for good.
If texting 'is starting to feel frustrating, stressful, or if you're overwhelmed or trapped by it, that's a good indication that you need to set a boundary.'
I am not known for being especially easy to get hold of via text. I tend to keep my phone on silent as the high-pitched ping of an incoming message makes my cheeks flush with dread. I wish I could mute all my contacts' notifications – sorry, mom, dad, and everyone I care about, but communicating with you makes me incredibly anxious.
But, obviously, that's not feasible. I do, however, mute text threads with more than three people, and I opt out of family threads entirely. It is a small gesture, but bowing out of these communal conversations eases my mind, even if I sometimes feel left out and lonely – not to mention guilty that I've made my family feel like an annoyance.
Yet I've found that ignoring my family for the sake of my sanity can be therapeutic. Smartphones seem to cause more trouble than they're worth: these devices have opened up a universe of new ways for people (not just family) to bother us. One study from the American Psychological Association in 2017 found that constantly checking emails and texts contributes significantly to our overall stress. Nancy Cheever, professor of communications at California State University, Dominguez Hills, researches how cellphone use affects our moods, and says that being 'constantly connected' through email, text and social media guarantees that you'll experience anxiety. The distraction seeps into your work life, too: as Scott Bea, a psychologist at the Cleveland Clinic in Ohio, told the Daily Mail last year, constantly checking your notifications can drop productivity by about 40 per cent.
Sometimes, it's impossible to avoid texts from work, but you can give yourself permission to take a break from texting with family. Writing for Psychology Today in 2014, Theresa DiDonato, a social psychologist at Loyola University Maryland, said that constant texting can lead to 'a cycle of mobile relationship maintenance', in which 'individuals begin to feel an overdependence', potentially violating your sense of privacy and autonomy. The otherwise innocuous act of texting can then strain close bonds between loved ones, and even create feelings of resentment toward people who are probably well-intentioned, but unaware of the toll of their excessive communications on your psyche.
If texting 'is starting to feel frustrating, stressful, or if you're overwhelmed or trapped by it, that's a good indication that you need to set a boundary', I was told by Dana Gionta, a clinical psychologist in Connecticut and the co-author, with Dan Guerra, of From Stressed to Centered (2015). For most people, she notes, a barrage of text messages leads to an unwelcome – even distressing – distraction. That would hold true for text messages from anyone, but what makes it extra-frustrating from family is that the distraction is now coupled with a feeling of obligation. There's pressure to get back to a family member and this can weigh on you while you're trying to accomplish other tasks.
If you're receiving a stream of (non-emergency) texts from loved ones (on subjects ranging from, let's say, family gossip to plans for a visit or critiques of films), you'll probably feel required to read each one to keep up with the conversation. The result is what Mark Dombeck, a psychologist in California who has written extensively about boundary-setting and assertive (as opposed to aggressive) behaviour, calls a 'cognitive load' that you might find difficult to take on in the midst of other responsibilities. Yet your responsibility to family will inevitably seem more urgent, and weigh heavier on you, than all the others. 'Family relationships are important to most people and there will be a motivation to follow social protocols and respond when queried, creating a feeling of pressure which might not be present in relationship with a stranger,' he notes.
There are gentle ways to broach the topic of texting without offending your family. You might be right to feel irritated if they act as though texting is an open invitation to relentless communication, but it's crucial that you don't lash out, or respond when you're feeling angry or annoyed. 'When people come into your territory, and they are being disrespectful, you have the right to defend yourself,' explains Dombeck. 'Not to attack them but to defend yourself.'
What you must do, he tells me, is make an assertive statement. Assertion is the 'fulcrum, the balance point' between aggression and passivity. But unlike aggression, assertion shouldn't come from a place of hostility. When it comes to gently asking family to stop texting you, that means being straightforward and firm. 'Please text me only for true emergencies' is the kind of language he suggests.
Gionta, meanwhile, recommends a gentler approach. You don't have to share that you're feeling overwhelmed or frustrated by the text messages, she emphasises, and you should make it clear that cutting down on texting doesn't have anything to do with how much you love the person in question. Provide a vague reason – 'I'm finding it hard to keep up with all the text messages and emails that I'm receiving' – and then negotiate a timeframe to respond that works for both sides. Try a line such as: 'I would love for us to stay close, however daily texting isn't working for me. Could we try twice a week?'
Confronting the issue is probably the simplest part of this scenario. It's the reaction, and the ensuing guilt, that turns out to be the most emotionally straining. In fact, the thought of dealing with blowback from your family can be enough to stop you addressing a frustrating issue altogether.
'The reality is most people only know aggression and passivity, and they think of anything that isn't passive as being aggressive,' Dombeck says. 'In doing this, you are making a decision: are you going to do what you need to do to maintain your peace of mind, which might alienate other people in the family system? All you're doing is saying that you refuse to be abused. Other people won't see it that way. You have to become willing to stand your ground.'
While we can't control or predict how other people will react to our actions, Gionta adds, we can control 'how we express ourselves and the level of consideration and respect that we use'. As long as you state your case calmly and with kindness, you shouldn't feel beholden to someone who guilt-trips you, or makes you feel obliged to participate in a text thread that stresses you out.
You should also feel empowered to completely ignore people with toxic responses. Dombeck says that, in families where one person feels entitled to power over others, 'any encroachment on that power is going to feel aggressive'. Those people might demand that you justify your actions or subject you to so-called flying monkeys: other family members who have been dispatched to check on you.
So why invite the drama? Wouldn't you be better off simply ignoring the messages, never speaking up about how each new one brings you one step closer to panic? Dombeck thinks it is an issue worth addressing because an overabundance of texting likely points to a pattern between you and your family members. 'If this is happening in text message, it's been happening in all mediums of communication. This is not some unique isolated behaviour. When you ask: "Is this the hill I'm going to die on?" you have to understand that the hill is not limited to text messages but the whole history of communication.'
This article was originally published at Aeon and has been republished under Creative Commons.
Forty percent of Americans sleep less than seven hours per night, and that's a problem.
Of the many pieces of folk wisdom handed down through the generations, the necessity of sleep is of primary importance. While sleep research was effectively in the dark (pun presented but not intended) for eons, the list of benefits of a good night’s sleep—better memory retention; stronger immune system functioning; better attentional control; less aggressive and impulsive behavior; less need for sugars and carbs, implicated in willpower studies—has changed our understanding of the time we spend “doing nothing.”
Which is why new research published in the journal, Sleep Medicine, should be alarming. Thanks to the increased usage of social media and smartphones, teenagers are losing sleep at alarming rates. While seven hours a night is recommended for adults, adolescents require nine, given the continuing formation of brain circuitry, especially the prefrontal cortex where many rational decisions are made. We don’t make the best choices when groggy.
Analyzing a whopping 360,000 teenagers, a team led by San Diego State University Professor of Psychology Jean Twenge found that 40 percent of teens slept less than seven hours a night in 2015. Teens who spend five hours or more a day online were significantly more likely to fall into this group than teens online for an hour or less.
This disastrous phenomenon is not limited to teens. As Twenge concludes,
Given the importance of sleep for both physical and mental health, both teens and adults should consider whether their smartphone use is interfering with their sleep. It’s particularly important not to use screen devices right before bed, as they might interfere with falling asleep.
Forty percent is also not a number limited to teens. Turns out that’s also the total number of Americans getting less than seven hours of sleep every night. Respondents 65 and older were in the highest group, with 67 percent claiming at least seven hours, while parents of young children and lower-income workers struggle to achieve that number. Young adults also fall short of the mark.
This has led sleep scientist Matthew Walker to proclaim a disturbing reality for many young Americans today:
Not only does sleep disruption play a role in the declining mental abilities that typify Alzheimer’s disease, but getting enough sleep is one of the most important factors determining whether you will develop the condition in the future.
Walker points to the fact that sleep helps memories become solidified in the architecture of the brain. The creation of long-term memories is integrated from experiences into the fabric of your history, and therefore identity, though the process of sleep.
Yet humans are terribly complacent when considering best practices involving the future. A smoker knows cancer is likely around the corner, yet puffs anyways; the same goes for alcoholics and cirrhosis, obesity, and other diseases. Most drivers recognize that texting while behind the wheel results in over 400,000 injured or dead every year, yet that’s always the other person—it could never happen to me. Chances that you’ll ply the phone from a teen or adult with a promise of decreased risk of dementia decades from now are minimal.
But the lack of sleep is harming us, now. The National Sleep Foundation estimates that 47 million Americans don’t get restorative sleep, with real world consequences: our insomnia costs the US eighteen billion dollars a year in lost productivity and accidents. Speaking of accidents, 20 percent of car crashes—1.2 million—are attributed to tired drivers.
Preempting the problem with sleeping pills is not the path forward. Pills like Ambien and Rozerem have been shown to only increase sleep seven to nineteen minutes per night, with a host of attendant side effects (including, amazingly, insomnia).
Sleep is such big business that it is now considered a sign of status. On certain days I work in Beverly Hills and Hollywood, regions of Los Angeles where plastic surgeries that make you look inhuman are markers of affluence. That something as basic and primary as a good night’s sleep is now part of our fragmented cultural milieu is highly disturbing. We live in a competitive society already. Bragging about your proficiency in being unconscious is not a sign of a developed mind.
We should all be getting a good night’s rest. If that means restructuring society to accommodate such a goal, so be it. Rising rates of inattention and dementia are not helping our economy, relationships, or much of anything. In a nation that has offered so much to science, that we can’t get the basics down is a dangerous signal that something is systemically wrong.
Derek is the author of Whole Motion: Training Your Brain and Body For Optimal Health. Based in Los Angeles, he is working on a new book about spiritual consumerism. Stay in touch on Facebook and Twitter.