'Positive deviance' and the power of outliers May 8, 2024

'Positive deviance' and the power of outliers

May 8, 2024

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Groundbreaking solutions in cities are often the result of visionary mayoral leadership. But sometimes certain communities achieve significantly better outcomes than their similarly resourced neighbors—and the underlying reasons may not be immediately obvious to local leaders. Ravi Gurumurthy, CEO of the global innovation foundation Nesta, believes that this variation in quality of life at a hyper-local level is something worth paying a lot more attention to. 

“The fastest way for us to improve people's lives will be to mine that variation and really understand what is going on,” he says.    

This concept, known as "positive deviance," describes individuals or communities that achieve remarkable success or exhibit highly effective behaviors despite facing the same constraints as their peers. With a long history of use in international development, positive deviance is now gaining traction among city leaders as a source of solutions to stubborn urban challenges.  

Here's a closer look at what it’s about, and how it’s already being used to uplift promising approaches in cities. 

What is positive deviance? 

Positive deviance first gained widespread attention because of a remarkable success story in 1990s Vietnam. Much of the country was suffering from a malnutrition crisis, and efforts to design and implement new solutions were coming up short. But aid workers landed on a breakthrough by paying closer attention to children who already appeared larger and healthier than their peers.  

It turned out these children were being fed different diets—leaning more heavily on shrimp and crab, for example, which were widely accessible but less often fed to young people. These children also were being fed more frequently, in smaller meals, throughout the day—an intervention that, again, did not require parents to have more resources so much as to differently use what was universally available.  

When these practices—feeding kids shellfish, and making meals smaller and more frequent—were replicated, malnutrition plummeted. 

What does positive deviance look like in cities? 

Positive deviance is an inherently local phenomenon, whether it’s a village in Vietnam or a major metropolis. In Mexico City, a promising pilot initiative demonstrates the potential of leveraging positive deviance to take on a persistent local challenge: public safety.  

City leaders, including those from the Bloomberg Philanthropies-supported Digital Agency for Public Innovation (ADIP), conducted a thorough analysis of crime data at the most granular level in the hope of reducing violence against women. Their work grouped city precincts together based on core characteristics such as population density, commuter volume, and socioeconomic conditions, including housing and income statistics. Then—despite some limitations in the data due to potentially unreported crimes—they identified parts of the city with fewer incidents than a statistical model predicted based on those characteristics. By including a search for positive deviance as part of its problem analysis, the city was able to identify areas that were overperforming—and in turn, opened the door to understanding what unique factors contributed to that outcome.  

This work helped city officials identify specific neighborhood characteristics that seemed to correlate with safer environments for women—and develop interventions that could be tested at scale. 

One such strategy involved the removal of abandoned buses and other vehicles identified as possible contributors to violence against women. Another called for encouraging some businesses to vary their operating hours to ensure a consistent presence of women, girls, boys, families, and older adults on the streets, thus potentially enhancing safety in critical areas. 

Where are there opportunities for cities to draw upon positive deviance? 

Positive deviance work digs into the success stories of outliers to uncover the driving factors behind their achievements. In North Macedonia, an effort to use a data-powered positive deviance approach similar to the one in Mexico City was deployed with a focus on municipal finances—and how cities might learn from others how to better manage their budgets. 

In this case, positive deviance was uncovered by looking at national and local data to identify municipalities that had less debt. What the study found after comparing similar localities was that there were specific capacities, like the use of better accounting software and participatory budgeting, present in the most fiscally sound communities. That insight laid the groundwork for practical action: In Skopje, for example, Mayor Danela Arsovska—who has participated in the Bloomberg Harvard City Leadership Initiative—decided to dedicate funding from the city budget to replicate some of the capacities that helped other cities stand out.  

As Gurumurthy explains, “Sometimes we assume that, with innovation, we have to start from scratch.” What positive deviance work demonstrates, he adds, is that cities can also “start by actually understanding and appreciating” existing successes—and then build upon them.