The Academy of Motion Pictures and Sciences is a mysterious beast. Just when it appears to have become lamentably, irrevocably predictable -- it goes and stuns us.

Take for example a little film called "Crash." Its upset last year of odds-on favourite "Brokeback Mountain" left more than a few audience members, TV viewers and Oscar poolers staring in open-mouthed shock.

That win just went to prove that trying to predict the whims of 5,800 or so people -- the estimated membership of the Academy -- is never simple. And that is exactly what makes Oscar pools so much fun.

The key to winning is to learn your Oscar history and try to get into the Academy's collective mind. So here are a few of the distinct patterns in Oscar wins that have emerged over the years:

1. Dramas are much more likely to be nominated and win the Oscar than comedies, action-adventures, suspense-thrillers, or Westerns.

In the last 10 years of Best Picture wins, only "Shakespeare in Love" would qualify as a comedy (though some would disagree). And while other films have had adventure elements, none could be strictly defined as action-adventures.

2. Films inspired by real-life individuals are often winners.

In the last 25 years, we've seen "Gandhi" (1982), "Amadeus" (1984), "Schindler's List," "Braveheart" and "A Beautiful Mind" (2001) walk away with the Best Picture Oscar. Everyone loves a story that involves someone battling adversity.

3. Epic films over two hours with large-scale productions are often rewarded.

In the last 15 years, we have had "Dances With Wolves" (1990), "Braveheart" (1995), "The English Patient" (1996), "Titanic" (1997), "Gladiator" (2000) and "The Lord of the Rings: The Return of the King" (2004) all walk away with the Best Picture Oscar. Perhaps not coincidentally, all were big winners at the box office as well.

4. Period pieces are often favoured.

A full 85 per cent of the Best Picture winners of the last 20 years took place in non-modern day settings. Perhaps the Academy likes films that allow it to escape to "a better time"?

Epic war films and musicals, once sure winners, have fallen out of favour.

The two notable exceptions in recent years are "Schindler's List" (1993), and "Chicago" (2002). But others such as "Moulin Rouge," "Saving Private Ryan," "The Thin Red Line" have been passed over.

We can even take some of the Academy's patterns and turn them into easy-reference statistics:

  • Odds over the last 20 years that the film with the most Oscar nominations has won Best Picture: 9 out of 10
  • Odds in the last 10 years that a film winning a Best Picture Oscar won at least two of the three guild awards (Writers Guild, Producers Guild, Directors Guild) for which it was eligible: 4 in 5
  • Odds in the last 20 years that the Directors Guild of America winner directed the Best Picture Oscar winner: 3 in 4
  • Odds in the last 20 years that the Best Picture winner will also receive the Best Director award: 3 in 4
  • Odds in the last 20 years that the Best Picture winner will also receive the Best Actor award: 1 in 4
  • Odds in the last 20 years that the Best Picture winner will also receive the Best Actress award: 1 in 5
  • Odds, in the last 20 years, that the Best Picture winner will have no acting nominations whatsoever: 3 in 20

Of course, patterns are just a guide. Heaven knows there have been many "What were they thinking?!" Oscar moments over the years that defied all expectations.

So who are these people who make these award bizarre decisions? No one really knows, since the Academy doesn't reveal the names of its members.

Members enter the Academy after being invited to join. They must be sponsored by at least two members of the branch for which the person may qualify, such as an actor being nominated by two other actors. And they must meet certain criteria such as having film credits of a calibre that reflect the standards of the academy, making an outstanding contribution to film and receiving an Academy Award nomination.

Since no one knows who makes up the Academy, it's not easy to generalize about them, but based on history, herewith is a guide to the collective Academy mind:

It's notoriously sentimental

The Academy is a sucker for a tearjerker. The examples abound, but here are a few examples of tissue films stealing wins: How Green Was My Valley's win in 1942 over Citizen Kane; Rocky's win in 1976 over Network, Taxi Driver, and All the President's Men; Kramer vs. Kramer's win over Apocalypse Now in 1979; Ordinary People's win over Raging Bull in 1980.

It prefers "popular" actors

Academy members seem to like "nice guys", those actors who have ordinary looks and often play ordinary people characters. A few examples: Tom Hanks, Jimmy Stewart, Katharine Hepburn, Helen Hunt.

It has a guilty conscience

The Academy often hands out Oscars to actors or directors who it believes have been too long overlooked or passed over. Paul Newman's Best Actor win for The Color of Money (1986) and Henry Fonda's win for On Golden Pond come to mind. Fonda had been nominated twice before and Newman seven times before they finally earned their wins in film that few would call the vehicle for their greatest ever performances. Interestingly, in both cases, both had received honourary awards from the Academy just the year before their wins.

There are plenty of other factors that can influence Academy members' decisions: studio promotion, box office receipts, and personal relationships are just a few. The Academy insists it does not tolerate bribes, promotional gifts, or other unethical lobbying tactics, but it's difficult to assess how effective their policies are since the Academy polices itself.

In an ideal world, the film with the most worth, the most artistry and the most innovation, and the actor who worked the hardest would walk away every time with the win. But we all know that isn't the way it happens.

In the end, Oscar poll players need to do exactly what Academy members should do before marking their ballots: see all the films nominated, read the reviews, keep your ears open to the buzz and most importantly, go with your gut.