Email Efficiency is Relationship-Sensitive [STUDY]

A new study out of Northwestern University indicates that our email efficiency is relationship-sensitive -- specifically, we reply sooner to emails from close friends than strangers. Researchers Stefan Wuchty and Brian Uzzi studied 1.5 million messages sent by 1,052 employees and uncovered an algorithm that reveals the closeness of a relationship based on how long it takes for the individuals to reply to each other's emails.

Here are the hard numbers from the study, as covered by Jonah Lehrer in The Wall Street Journal:

People reply to their close friends, on average, within seven hours of getting the email, the data show. Professional contacts take a bit more time: We don't hit send for nearly 11 hours. But the biggest difference came when the scientists looked at those people we barely know. On average, it took us 50 hours to reply. In other words, there's a surprisingly easy way to figure out how you feel about someone -- just count the hours before you hit the "reply" button.

The study's findings ring especially true as we head into the first workweek of 2012, likely mired in email. As you tackle your inbox, spend the most time on emails from close friends or colleagues, and spend less time on nonessential notes from strangers. And if you're still harboring email from 2011, consider this Chris Brogan tweet from Dec. 30:

Haven't replied to that email in over 14 days? You won't. Delete ALL. Make room for 2012.

— Chris Brogan (@chrisbrogan) December 30, 2011