Actors appearing in comedy films are nine times less likely to receive an Oscar nomination than those performing in dramas, according to a new study.
And the male domination of Hollywood means that acclaimed actresses are twice as likely to get the nod for an Academy award than their male counterparts, a survey by the University of California Los Angeles and Harvard University found.
Researchers examined records from the Internet Movie Database, looking at every film eligible for the Oscars between the inaugural ceremony in 1927 and the 2005 show.
After the study of 171,539 performances by 39,518 actors in 19,351 films, it appears probable that movies classed as dramas are far more likely to dominate tomorrow's announcement of the 2008 nominees than comedic films.
"In the entertainment industry, there's long been a sense that the nomination process prefers dramas, but I don't think anybody is aware of the magnitude of the effect," said study co-author Gabriel Rossman.
"The odds of being nominated for an Academy award are so much greater for performers who appear in dramas that - at least this time of year - it really pays to be a drama queen."
And for actresses, the "under-representation" of women in film means they have a greater chance of receiving an Oscar nod than their male co-stars, according to co-author Nicole Esparza.
"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 than actors," she explained.
"It's a simple matter of arithmetic."
The study also found that actors with a previous Oscar nomination under their belt had an increased chance of being nominated a second time.
"This is an instance of what sociologists call the 'Matthew Effect,' after Matthew 25:29, in which Jesus says, 'For to everyone who has, more will be given and he will grow rich,'" Esparza explained.
"Just as the rich tend to get richer and popular web sites get even more traffic, so do honours seem to pile onto those who have already been honoured, be they scientists or movie stars."
Other factors central to the probability of securing an Oscar nomination included the prestige of the film's distributor, the number of films released in a given year and the award nominations already accrued by an actor's co-stars and the movie's crew.
The 2008 nominations are announced at 05:30 local time (13:30 GMT) at the Samuel Goldwyn Theatre in Beverley Hills, Los Angeles.
The '12 Years A Slave' director will receive the accolade at the London Film Festival in October.
Critics from all over the world were asked to name the best movie of the past 16 years.