On Twitter, power is in numbers. But true influence isn't in the number you'd think. It's not about how many people follow you, but rather how often people mention you.

In David Leonhardt's new column on lists for The New York Times Magazine, the economist teams up with an independent research firm called Twitalyzer to produce an Influence Index to rank the most powerful people on Twitter.

It counts the number of times somebody's Twitter name is mentioned by other users (including retweets, which occur when one user rebroadcasts another's message). The Influence Index doesn't merely measure who's talking on Twitter, but it also measures how much someone is affecting the conversation. Look below at how low Lady Gaga's influence score is, for example.

Topping the list is Rafinha Bastos, a Brazilian comedian and TV reporter whom I'm not familiar with. Number two is Chad Ochocinco, the loud wide receiver for the Cincinnati Bengals. Lady Gaga, the most followed person on Twitter, comes in 41st.

Read the full story at New York Times Magazine.