About 1.5 million dogs and cats are euthanized in shelters each year because they weren’t adopted or had health problems that concerned potential owners.

Agencies often use “Adopt, Don’t Shop!” campaigns to encourage people to adopt from or donate to shelters, but their effectiveness can be limited. How can adoption agencies persuade people to rescue pets who need a home?

In a paper published on Dec. 26, I investigated the pet adoption problem using advertisements from the online database Petfinder. The paper quantified the language patterns of nearly 680,000 adopted and unadopted pet ads.