In his study, published July 19, Calzolari explained that many businesses were creating corporate Twitter accounts to promote their products and sometimes acquired fake "followers" in order to boost their statistics in relation to those of their competitors.
He had developed an algorithm capable of distinguishing between real followers and computer bots, he claimed, and had applied the program to a random sample of 20,000 of Grillo's Twitter followers.
Human followers could be identified because they themselves had at least 30 followers, used punctuation in their posts and had submitted them via other sites such as Instagram, Calzolari explained in the study.
Grillo's admirers were particularly infuriated because the study focused only on the leader of the Five Stars Movement, whose use of the Internet mirrors that of Barack Obama, whose journey to the White House was in part propelled by "likes" and followers on social media.
Calzolari remedied the oversight with a new study published Wednesday. In it he claimed 59% of Grillo's 637,000 followers were bots, 24% human, with a further 11% uncertain and 6% inaccessible behind privacy screens. This time, however, he provided information on other leading politicians, which showed center-left leaders with the largest number of Twitter followers but still at least 400,000 behind Grillo, and with correspondingly high levels of bot followers -- in the 45% to 48% range.
The center-right lagged behind, with Angelino Alfano, secretary of Berlusconi's People of Freedom Party, notching a miserly 30,000 followers, 25% of them bots, and the 76-year-old Berlusconi not present on Twitter at all.
Advised by Gianroberto Casaleggio, a fuzzy-haired Internet guru whose Casaleggio Associati looks after his blog, Grillo has used the Internet to organize his movement and communicate its eclectic mix of environmentalist and futurist policies to the outside world. Commentators have described the movement as an autocratic version of Germany's Pirate Party.
The newly elected Five Star Movement mayor of Parma, Federico Pizzarotti, has introduced live streaming for council meetings and regular YouTube messages to keep citizens informed, bypassing the filters of the mainstream media.
Having been banned from television as a comedian because his corrosive satirical attacks embarrassed the country's leaders, Grillo has turned his absence from the nation's talk shows from a weakness into a strength.
"Grillo has cancelled television and he asks his supporters not to go on it, excluding them from the principal platform of political discourse. He has cut out television and substituted it with Internet," said Gianni Barbacetto, a Milan-based journalist who has followed Grillo's astonishing rise.