This one comes from a UCLA researcher who counted only 472 dispensaries - far fewer than the 800 estimated by Police Chief Charlie Beck or the 1,000 suspected locations cited by the City Attorney's Office (I've seen estimates of 500 as well). Not to state the obvious, but if there's such wide disagreement on the number of dispensaries, how on earth did the city expect to enforce the ban (which has since been suspended because opponents gathered enough signatures to put the matter to the voters). From the UCLA Newsroom:
To determine the actual number of dispensaries in operation, the researchers compiled lists using multiple electronic and hard-copy sources, including the city's finance list. These lists referenced 875 unique locations, including 762 dispensaries registered with the city. When the researchers went to these locations, they found that only 472 were actually operating as dispensaries. "Some of the locations we visited had previously been dispensaries but were no longer open," said [Bridget Freisthler, an associate professor of social welfare at UCLA's Luskin School of Public Affairs], Freisthler, adding that a significant portion of these businesses had never been operating as dispensaries and instead had been other businesses for decades or were addresses to postal boxes. All of the visits were made during the past three weeks.
Earlier: Why the effort to regulate medical marijuana is close to hopeless