Habit and Skill Retention in Recycling

Dylan Brewer
Team Members
Samantha Cameron
About This Project

Assistant Professor Dylan Brewer and School of Economics alumna Samantha Cameron's article "Habit and Skill Retention in Recycling" was conditionally accepted to the Journal of Policy Analysis and Management. Brewer writes:

It is widely believed that habits are an important input to residential and municipal recycling, but there is little research on the persistence of these habits. In our paper, we study a 2002–04 pause in the collection of glass and plastic recycling in New York City. This pause serves as a natural experiment that allows us to learn how persistent recycling habits are. If habits can be easily disrupted, we would hypothesize that New York City's recycling rate would be lower when glass and plastic recycling resumes and would take time to rebuild. A quick recovery of recycling rates would suggest that recycling habits are persistent.

We find that New York City's recycling rate essentially fully recovered in the first full year that recycling resumed. Our research design compares New York City recycling rates to municipal recycling rates for counties and cities in New Jersey and Massachusetts that did not pause glass and plastic recycling collection, which serve as control groups. Relative to these controls, New York City's recycling rate declines as expected during the pause but then fully recovers in the first full year of recycling post-pause.

These findings are important because recycling is hotly debated and is not always cost-effective. For example, after China stopped purchasing US recycling in 2017, the value of US recyclable material fell, putting budgetary pressure on municipal recycling programs. For a recycling manager, there may be concerns that pausing recycling collection would worsen recycling habits. Indeed, some municipal recycling programs have continued to collect recycling separate from other waste but have sent the recycling to the landfill. Our research provides the first evidence that habits are persistent and may not be affected by a brief pause in recycling collection.


From 2002-2004, New York City ceased collecting residential glass and plastic recycling due to city budgetary pressure. We use data on recycling rates in New York City, New Jersey, and Massachusetts in a difference-in-differences (DID) research design to determine whether this exogenous pause weakened previously formed recycling habits. Despite a 50% decline in the overall recycling rate in 2003, by 2005 the overall recycling rate had fully recovered. Our results suggest that recycling habits are persistent in the short term and that the loss of previously established recycling habits and skills are not an unintended harm of pausing a recycling program. We show that these results hold in the standard DID approach, as well as a synthetic DID approach modified to estimate time-disaggregated treatment effects separately, which eliminates pre-trends and improves the precision of our estimates.

Until the article is published in the Journal of Policy Analysis and Management, you can read it here: https://www.dylanbrewer.com/wp-content/uploads/2023/01/BrewerCameron_2023.pdf