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Gentrification, that once-wonky, now common concept, is a term freighted with moral urgency, resentment, and guilt, because almost nobody in a high-cost city can avoid it. You’re either suffering its effects or inflicting them, often both at the same time. Unless you leave town altogether — as hundreds of thousands of people of all income brackets do every year — saying good-bye to one neighborhood makes you a newcomer in another. At its most basic, gentrification is what happens when newcomers to a neighborhood arrive with more income or education than those who already live there. At its most politically charged, it’s treated as a form of colonialism, ethnic cleansing, even genocide. Yet gentrification’s status as a great urban evil, a ravager of lives and destroyer of communities, is based as much on faith as on fact. Most scholarly research on the topic compares snapshots of cities and neighborhoods at different times but loses track of what happens to the actual people who live there.

Now, a pair of studies has used Census micro-data and Medicaid records to track specific residents of both gentrifying and non-gentrifying neighborhoods — where they live, where their children go to school, when they move, and where they go. The researchers come up with some startling findings. In a paper published by the Federal Reserve Bank of Philadelphia, Quentin Brummet and Davin Reed say that urbanites move all the time, for countless reasons, and that gentrification has scant impact on that constant flow. Those who stay put as a neighborhood grows more affluent often see their quality of life rise and their children enjoy more opportunities. Those who leave rarely do worse.

In a separate study at NYU by Kacie Dragan, Ingrid Ellen, and Sherry A. Glied, published by the National Bureau of Economic Research, the researchers used Medicaid records to track thousands of children from address to address, between 2009 to 2015, a period of boiling gentrification. They found that schoolkids who lived in neighborhoods that saw an influx of college graduates didn’t move away more often than their peers in less fluid areas. Taken together, the papers suggest that gentrification’s upsides for longtime residents not only exist but go a long way toward mitigating the pain it causes. Citing previous research, Brummet and Reed say that “exposure to higher-income neighborhoods has important benefits for low-income residents, such as improving the mental and physical health of adults and increasing the long-term educational attainment and earning of children,” Brummet and Reed assert.

These papers measure the measurable and quantify the quantifiable. They are narrow in scope and limited in their conclusions. They don’t capture the sense of a familiar world slipping away, or what it feels like when the mix of languages and races on your block begins to change. They don’t address the disappointment of young adults realizing they can’t afford to rent near the blocks where they grew up. They miss the network of churches, groceries, sounds, and stores that dissolves when, say, a black neighborhood grows whiter, or an immigrant enclave breaks up. Emotions, culture, and economics interact in ways that resist statistical analysis.

It would be wrong to use this research to airbrush out all the injustices and calamities that the poor have to deal with, such as landlords making their tenants’ lives so miserable that they are forced to decamp. For NYCHA residents, the right to stay put comes with the need to put up with mold, lead paint, and extreme temperatures. Far from waving an intellectual wand over neighborhood change and declaring it all fine, they point out that low-income urbanites suffer chronic instability, whether their neighborhoods are metamorphosing around them or remain locked in poverty. At any given time, some would prefer to stay but find they have to move; others want to move and can’t. Pressure cuts both ways.

Even with all those qualifiers, though, the studies make it clear that the simple narratives of gentrification’s evil don’t hold up. A neighborhood is not a filled and stoppered bathtub, where for every drop that flows in, another must slosh out. It’s more like a wet sponge, with residents draining away and evaporating all the time, newcomers passing through or settling in, finding whatever crannies seem hospitable at any given time. The Philadelphia Fed paper concludes explicitly that changes in a neighborhood’s demographics are driven far more by who moves in than who moves out.

Shifting the emphasis away from displacement matters because it suggests that efforts to protect a neighborhood’s character are largely beside the point. Those who live there will move or stay, get used to the newcomers or not. They are not being evicted en masse, and they cannot be sheltered as a group. More people leave New York for the suburbs or other states than arrive from other places around the country — and that’s almost always been the case. Today, the city’s population is growing (slowly) partly because of the influx of recent college grads, but mostly because of births and arrivals from abroad. If you feel that the city is crowded enough, thank you very much, and can’t absorb another new New Yorker, then your problem is with immigrants and babies born within the five boroughs, not with an avalanche of tech bros.

The flow of population in and out gives New York much of its strength and some of its problems; sometimes the two are indistinguishable. A dysfunctional school system pushes many families to the suburbs; if it got stellar overnight, the city would become unmanageably clogged just as quickly. The odds of being murdered by a stranger on the street remains vanishingly low; if they soared, rents would suddenly become more affordable. The same is true at the neighborhood level: safer streets, fresher food, more welcoming public spaces, better transit, and greener parks improve the lives of old residents and attract new ones.

This complicated, unpredictable dynamic often gets boiled down to serve an agenda. Different prongs of the anti-gentrification movement offer mutually exclusive solutions. One extreme urges the construction of affordable housing: build it dense, soon, and everywhere. Any objection is inhumane. To fuss over open space, historical fabric, or the need for sun on parks is to care about the wrong things and the wrong people. The counter-faction sees new construction as the cause of displacement rather than the cure. “Affordability” is just a word to sugarcoat a developer boondoggle. The first group would like to see New York grow ever more towers, the second wants all the building to stop and for affluent newcomers to just go away.

In practice, most policies that combat gentrification protect the status quo. They encourage people to stay where they are and they slow the rate of demographic change. We have a constellation of good and worthy programs that protect vulnerable residents from being bullied or buffeted and allow them to stay in their homes if that’s what they want. The state’s newly reinforced rent regulations will be a boon to many (though the full range of unintended consequences have yet to make themselves fully known). Broadening the base of jobs, shoring up a beleaguered transit system, caring for parks and public space, shedding car traffic on city streets — these efforts can all mitigate against the economy’s persistent inequities.

But policies specifically aimed at keeping communities intact can be counterproductive. In many subsidized new buildings, for example, the city sets aside half of all affordable apartments for applicants who already live in the neighborhood. That’s a troubling practice because trying to keep communities intact through quotas often winds up perpetuating segregation. A report by a Queens college sociologist Andrew Beveridge, which the city hoped to suppress and a judge recently made public, found that, thanks to such set-asides, affordable-housing lotteries in predominantly white neighborhoods exclude African-Americans; lotteries in majority black neighborhoods reinforce the area’s racial makeup, with a result that racial borders remain artificially frozen.

Let’s say you and your spouse have two kids, two full-time jobs, two hour commutes, a household income of $64,000 (equal to 60 percent of New York’s area median income, or AMI), and a too-small apartment in Mott Haven. You keep tabs on affordable-housing lotteries around the city and, knowing how ridiculously small your chances of winning any one are, enter half a dozen at once. Neighborhood set-asides boost the odds that you’ll score an apartment in a new affordable-housing development nearby, which means keeping your children in a failing school and letting your life leach away on the long subway ride to work. But those same set-asides also substantially decrease your chances of getting out and moving to, say, the affordable apartments in a deluxe waterfront tower in Long Island City or Hudson Yards. It’s a policy that exhorts you to know your place.

Government should be making it easier, not harder, for people to change addresses if and when they want to. As newcomers roll in, with or without college educations, nobody has the right to tell them they shouldn’t or can’t. In the short term, gentrification makes neighborhoods more, not less, economically diverse and more racially integrated. The problem is that over time, those advantages dissipate, though not uniformly, and temporarily mixed neighborhoods become homogeneous again, and each new population in turn defends the turf it colonized. Diversity, not preservation, should be the goal. Instead of expending vast amounts of energy trying to shield fragile communities from change, we should make sure they reap its benefits.