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The classic version of The Wizard of Oz, released in 1939, is considered the most influential film of all time. But how the researchers got to the bottom of the matter is the coolest thing about this whole story. Scientists at the University of Turin have shown that the 1930s classic is the most cited film in other feature films.
“<em>Ok, but look at the number of Star Wars fans. How is he not the most influential movie in the world?"</em> Ok, it's a fact that a lot more people living today saw the George Lucas saga than the 1930s movie about the little Kansas girl. On the other hand, it's extremely likely that all Star Wars fans have heard the song <em>Over the Rainbow</em> or at least seen the photo that opens that note.
And that's where the leap is: according to the study, the most influential movie is the one that has the most references in other feature films - someone who appears singing Over the Rainbow in another movie, or a dialogue that mentions the classic of Oz.
According to the survey, The Wizard of Oz has had over 3000 citations in other films. Next come Star Wars (1977) and Psychosis (1960). Even removing the bias of old films in calculus (because they were produced earlier, they can influence a larger number of films), the world's 20 most influential feature films are all from before the 1980s - and most are from the US, of course.