How to improve your odds of picking a Melbourne Cup winner

AN analysis of 20 years of the Melbourne Cup’s first three horses suggests that punters should not be betting against the odds this year.

Jockey Michelle Payne, riding Prince Of Penzance, won the 2015 Melbourne Cup. picture: Colleen Petch

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BETTING against the odds paid off handsomely in last year’s Melbourne Cup, but history suggests it’s unlikely to be repeated on Tuesday.

While outsider Prince of Penzance’s stunning victory in 2015 showed that any horse can win, a News Corp Australia analysis of 20 years of the Cup’s first three horses suggests that punters should follow the odds.

Since 1995, more than half of the top three finishers had odds of 13 to one or better. In a typical Melbourne Cup, that narrows the picks down to four or five runners.

In two decades there have been just two Melbourne Cups — 2008 and 2012 — where all of the first three horses went into the race with longer odds, and 13 out of the past 20 winners had odds of 10 to one or better.

Prince of Penzance’s $101 odds in 2015 delivered some huge gains to a handful of lucky punters. One TAB punter put $2000 on the horse and won $252,000. Another punted turned $10 into $126,000 by predicting the first four horses past the post.

Statisticians say betting agency and bookmakers’ odds are not just based on the chance of a horse winning — they are modified to encourage people to bet on certain horses that improve the likelihood of bookies making a profit.

RELATED: Punters swayed by the ‘Payne effect’

Michelle Payne wins the Melbourne Cup on Prince Of Penzance in front of Frankie Dettori onboard Max Dynamite. Picture: Colleen Petch

Associate professor Scott Sisson, from the University of New South Wales School of Mathematics and Statistics, said it was further complicated by published odds changing with punters’ betting patterns.

“The bookies odds are not the same as the probability that any given horse will win,” said Prof Sisson, who also is president of the Statistical Society of Australia.

“So because you can’t trust these odds, you have to make your own judgments. And a great way to do this is to understand the data and results of previous similar races, and the past history of the running horses using statistics.”

Prof Sisson said if you believed the 101-1 odds, the chance of it happening again was once in every 101 races.

The field make their way down the straight at the start of the 2015 Emirates Melbourne Cup. Picture: Nicole Garmston

“What is the chance of two 101-1 winners in consecutive years? Well if these are the correct odds, and the races are independent from each other, then the odds are 10,201-1. Just multiply the odds. But again, these aren’t the actual odds, but rather the bookies’ odds designed to get you to put more money on particular horses.”

Financial strategist Theo Marinis said 2016 had delivered plenty of longshot winners so far — the Western Bulldogs in the AFL, Adelaide United and Leicester City in soccer, and the Chicago Cubs in US baseball.

“I’m not a betting man but it seems to be the year of the longshot,” he said.

Mr Marinis said while punters were speculators, bookies were investors. “They take in money, they diversify, if they have too much exposure to one they spread the risk, they play the percentages.”

He said Melbourne Cup punters should think like bookies and stay rational. “Set yourself rules and stick to those rules regardless.”

Originally published as How to improve your odds of picking a Melbourne Cup winner