City Hall in Center City Philadelphia.

City Hall in Center City Philadelphia.

Nudge in the City: Using Science to Improve Public Services

Cutting-edge technology is nice, but sometimes just changing the size of a mailing envelope can determine whether a program is successful.

Who would have thought that the size of an envelope matters? That’s exactly what behavioral researchers discovered when looking for ways to increase enrollment in a Philadelphia city program to provide low income senior citizens a discount on their water bills. 

While some federal agencies have pioneered the use of behavioral science insights to improve the effectiveness of their programs, cities are also getting in the game. Interestingly, several of the more prominent efforts are being led by alumni from federal initiatives.

Over the past decade, dozens of cities across the country have created innovation offices. Typically, these offices use a range of tools, such as data analytics, human-centered design, technology, and evidence-building. More recently, they have begun to use behavioral science techniques, as well.

The Philadelphia Experiment  

A 2014 City Accelerator grant from the non-profit Living Cities program was the spark behind the City of Philadelphia’s experimentation with behavioral science techniques. Its first initiative was to understand why eligible city seniors were not applying for discounts on their water bills. Researchers from the University of Pennsylvania, Swarthmore College and elsewhere explored whether program officials were failing to address citizen needs or whether eligible seniors were simply unaware of the program. 

According to a case study by Results for America, the researchers engaged city leaders from various departments, including the Department of Revenue, to identify key service touchpoints and evaluate how the program was operated. Ultimately, they experimented with different types of messages and forms of outreach—phone calls, postcards, and different sizes of envelopes in mailings—to see if one approach worked better than others. The final evaluation concluded “Every intervention showed a positive statistically significant impact on program enrollment, with the largest effect resulting from large envelopes, showing a 9% bump in participation.” And the best part? The solution was a low-cost tweak to existing operations.

In 2016, newly-elected mayor Jim Kenney expressed interest in deepening the city’s capacity to use social science and evidence-based evaluation of outcomes. He understood that it needs to be built in at the design stage of new policy initiatives and woven into the culture of how city managers operated. He hosted a forum of city and academic leaders to develop an initiative around using behavioral science techniques to make city programs and services more responsive to citizens. This collaborative effort was dubbed the Philadelphia Behavioral Science Initiative and the mayor’s director of policy, Anjali Chainani, oversees it. 

Ultimately, the mayor created a new innovation hub, GovLabPHL, that houses data analytics capabilities, evidence-based practices, and tech initiatives, along with the behavioral science projects, and put Chainani in charge. This hub is a multi-agency team that partners with local academics to use data and research on projects ranging from reducing delinquent taxes to litter control to increasing the use of bike sharing programs.

Chainani told Governing last year: “If we can better connect policy improvements [through behavioral science] to on-the-ground service delivery processes and tools, then we can be more effective in holistically enhancing the public’s experiences with city services.”

One of Chainani’s academic partners, University of Pennsylvania’s Dan Hopkins (who is a former federal behavioral science alumni), said, “a precondition to success [in a behavioral science initiative] is having someone who is part of the top leadership or policymaking team who understands behavioral science and can identify opportunities to use it as an intervention strategy to address an identified challenge.”

Other cities have undertaken similar efforts, oftentimes under the auspices of a broader innovation initiative. Some of the more prominent include:

District of Columbia. With support from an Arnold Ventures grant, District mayor Muriel Bowser launched Lab@DC in 2017  to conduct evaluations to “learn how well things work and how to improve.” Like the Philadelphia initiative, it involves partnerships, collaboration, the use of existing city administrative data and behavioral science insights to tailor interventions that are low cost and practical to implement. The Lab’s founding director, David Yokum, assembled a multidisciplinary team of about 15 to work with city agencies on a range of projects.

Like many of its peers, Lab@DC was initially a grant-funded pilot effort, but after demonstrating its worth to city leaders, it began receiving city support. Behavioral science related projects to date include a randomized field experiment on the effectiveness of different signage to reduce littering, the use of a nurse triage unit in the city’s 911 call center to direct true emergencies to ambulances and non-emergencies to primary care centers, and overhauling city paper forms to make them more citizen-friendly.

New York City. StateScoop, a newsletter covering state and local government, summed up New York City’s fledgling efforts in its use of behavioral science in 2018. Funding for the City’s behavioral design program has been extended through the end of 2019 based on initial successes demonstrated in pilot experiments in health, emergency response, and social programs.

Matthew Klein, executive director of the mayor’s Office for Economic Opportunity (NYC Opportunity), oversees the behavioral design program, which is supported by a nonprofit team of experts with He was enthused by the results of the pilot efforts and told StateScoop he “wants government to start thinking about behavioral design . . . What this does is bring a level of intentionality and science to examine how we work and to see if we can make changes to our practices that give a better result.”

For example, StateScoop reports, “New York City discovered it could get more people to show up to court if it sent text message reminders with information about potential penalties, how the process works and where people needed to go.”  Similar positive results occurred in experiments with encouraging residents to respond to surveys on flood insurance, increasing update of flu vaccines by city employees, and increasing recertification rates for food stamps.

Chicago. The Chicago-based MacArthur Foundation funded a pilot behavioral design program for the city in 2015, also choosing, to help organize the city’s efforts. Subsequently, the city found value in the program and continued funding the effort after the grant ended in 2017. According to, “They are now embedded in the city and have offices within the mayor’s office, where they use behavioral science to tackle some of the city’s challenges.” 

Recent initiatives include the reduction of congestion on the city’s transit system during sporting events by 17%, reducing single-use plastic bags by 40%, and reducing the number of parking violators who had to pay late fees for parking fines.

For example, Upswell writes, the city wanted to reduce the amount of parking tickets with fees that doubled before payment was made. When the behavioral design team looked at the timing of the notices that were being sent to violators, it found that the city wasn’t sending notices when the fines were about to double. By sending out postcards 10 days prior to the fine doubling, the number of tickets paid on time increased sharply—saving citizens money.

Lessons for Creating New Initiatives 

What steps should other cities take if they want to create their own behavioral insight initiative? Philadelphia’s Chainani and Swarthmore professor Syon Bhanot, developed a handy checklist based on their experience. Some of their key lessons include:

  • Go local—partner with local universities.
  • Clearly define the partnership between agencies and academics up front.
  • Emphasize cost savings that may result from the effort.
  • Make the process easy for participating agencies. 
  • Embed behavioral science initiatives into broader initiatives (e.g., in Philadelphia, it was embedded into the larger GovLabPHL).

More detailed guides have been developed as well. For example, the New York City effort created a playbook for cities based on its experience. But the key takeaway is this: Just get started!