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The urban myth that New York City has as many rats as people has been debunked. According to 26-year-old statistician, Jonathan Auerbach, there are only about 1.5 to two million rats.

For this study, Auerbach factored in all classified rat sightings, which totaled around 842,000. This data came from the city's 311 call logs. Based on the location and frequency of the sightings, he was able to estimate that there were about 40,500 rat colonies, which make up around 4.75 percent of the city's 842,000 lots. Since previous data suggest that there are about 40 to 50 rats per colony, Auerbach was able to conclude that there are about 2.02 million rats, a number he believes could be an overestimation.

"While the rat population remains a serious problem in New York City, there appears to be no evidence supporting the 8 million number. In problems like this, the city's open data is invaluable for challenging rumors, evaluating community need and establishing government efficacy," said Auerbach, who won the YSS/Significance Young Statisticians Writing Competition, reported in the press release.

Auerbach noted that conducting rat census had its limitations. For example, he could not catch a large group of rats to mark in order to avoid over-counting. He jokingly said, according to the New York Times, "Animals are terrible survey respondents."

"Anybody who knows anything about rats knows there aren't eight million rats," commented Robert Sullivan, who authored "Rats: Observations on the History and Habitat of the City's Most Unwanted Inhabitants." "But anybody who knows anything about rats knows that everybody loves the idea of eight million rats. The one-rat-per-person scenario is too good."

Auerbach is currently studying for a doctorate at Columbia University. His paper, "Does New York City Really Have as Many Rats as People?" was published in the journal, Significance.