Nominations for the 80th Academy Awards will be announced tomorrow, but for the actors at least they were all but decided months ago.

That was the conclusion from a study of all 1,394 nominations since 1927 carried out by sociologists at Harvard University and the University of California Los Angeles (UCLA).

They found that actors had a much better chance of being nominated for an Oscar if they were in a drama rather than a comedy, had been nominated before and surrounded themselves with acclaimed collaborators.

Less helpfully for the likes of James McAvoy (Atonement) and Tom Wilkinson (Michael Clayton), two Britons in contention for an acting nomination this year, the odds are also halved if you are a woman.

Tomorrow therefore holds more promise for Julie Christie, who is this year’s narrow front-runner for the Best Actress Oscar. In Away From Her she plays a woman with Alzheimer’s disease: this is definitely a serious drama not a comedy.

Christie has won the Best Actress Oscar before (for Darling) and been nominated twice. However, her chances would have been improved further if Sarah Polley, the debutante director who adapted the screenplay from an Alice Munro short story, had been nominated in the past.

Nicole Esparza, the study’s lead author and a specialist in health policy at Harvard, said: “It’s surprising how many variables other than a performer’s talent play a role in determining who gets nominated. A performer’s odds of being nominated are largely set before the cameras even start rolling, back when the script was bought, the director was signed and the film was cast.”

With Gabriel Rossman, an assistant professor of sociology at UCLA, Ms Esparza analysed data from the Internet Movie Database (IMDb) for all Oscar-eligible films made between the founding of the Academy of Motion Pictures Arts and Sciences in 1927 and 2005.

They considered 171,539 performances by 39,518 actors in 19,351 movies. Searching for conditions that improved the odds of a nomination, they cross-referenced the number of Oscar-eligible films in any given year, the distributors and studios behind each performer’s films, the film’s tone or subject matter, the cast size, the sex of the performer, the performer’s contacts within the industry and past Oscar nominations among a film’s cast, directors and writers.

The single greatest predictor of a nomination proved to be serious subject matter – or at least a film that was classified by IMDb as a drama. The researchers found that actors were nine times more likely to receive a nomination for their work in a drama than in a nondrama.

Mr Rossman said: “In the entertainment industry, there has long been a sense that the nomination process prefers dramas, but I don’t think anybody is aware of the magnitude of the effect.”

The second strongest predictor was the number of films screened in any given year, Mr Rossman said. Fewer films make the field less competitive.

Actresses are more than twice as likely to be nominated as actors for any given performance, the authors said. “At least in this case, being underrepresented on the job works in women’s favour,” Ms Esparza said.

“Because there are fewer female than male performers in films, and both are eligible for the same number of awards, actresses stand a better chance of being nominated. It’s a matter of arithmetic, but as far as I know, nobody has ever raised the point.” A previous nomination improved the odds, Ms Esparza added. Performers also received a lift when they appeared with previously nominated writers and directors.

The 80th Academy Awards are scheduled for Thursday at the Kodak Theatre in Hollywood, although fears remain that the Writers’ Guild strike could seriously disrupt the evening.

The Force

The lightsaber from the Star Wars films has been named favourite movie weapon in a survey by 20th Century Fox

1 Lightsaber Star Wars
2 .44 Magnum Dirty Harry
3 Bullwhip Indiana Jones
4 Samurai sword Kill Bill
5 Chainsaw Texas Chainsaw Massacre
6 Golden Gun James Bond
7 Bow and arrow Robin Hood
8 Machine gun Scarface
9 The Death Star Star Wars
10 Bowler hat James Bond – Goldfinger

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