With a week to go before the revelation of this year’s Nobel literature laureate, internationally renowned names including Irish Booker winner John Banville and Japanese favourite Haruki Murakami are edging up the odds at bookmaker Ladbrokes.

The Swedish Academy, the 18 members of which select the author they judge to have, in the words of Alfred Nobel’s will, “produced in the field of literature the most outstanding work in an ideal direction”, has yet to officially unveil the date its announcement will be made. But the Academy’s Per Wästberg told Swedish press that the winner would be revealed on 13 October, denying suggestions that the date had been delayed from 6 October because of members disagreeing.

On Thursday morning, Ladbrokes’ favourite to take the prize – at 4/1 – was the hugely popular Japanese novelist Haruki Murakami. Murakami was followed by another regular contender, the Syrian poet Adonis, at 6/1, with Philip Roth – despite the American novelist’s recent retirement from novel writing – at 7/1.

Ladbrokes put the esteemed Kenyan writer Ngugi wa Thiong’o fourth, at 10/1, the prolific American writer Joyce Carol Oates fifth, at 14/1, followed by Albania’s Ismail Kadare and Spain’s Javier Marías, both at 16/1. A host of writers including Irish Booker winner John Banville, Portugal’s Antonio Lobo Antunes, Norwegian Jon Fosse, Korean poet Ko Un, Hungarian novelist Laszló Krasznahorkai and Argentinean César Aira were given odds of 20/1.

“Murakami is top again – he’s there every year, but his fans more than ever think this could be his turn,” said Ladbrokes spokesperson Alex Donohue. “Banville is the best backed outsider; he is in to 20/1 from 33/1.” Bob Dylan, meanwhile, enters the lineup at 50/1.

The Swedish Academy never give any indication of who they may be considering for the prize in the lead up to the announcement of the winner. A shortlist of contenders is revealed 50 years later – so who was considered for 2016 prize won’t be known until 2066.

Over the course of the last 10 years, Ladbrokes’ favourite when betting was suspended has gone on to take the prize four times. According to the betting firm, “on average … at suspension of betting or the start of a race, the favourite wins 30% of horse races”.

Last year, the Belarusian journalist Svetlana Alexievich was at 2/1 when betting closed; in 2011 the Swedish poet Tomas Tranströmer was at 4/6, in 2009 German novelist Herta Müller was at 3/1, and in 2008 the French novelist JMG Le Clézio was at 2/1. Seven out of 10 times in the last decade, the eventual winner was in Ladbrokes’ top three when betting was suspended.

“If you look at the record of favourites, you do see slightly more win on average, but that could be due to a number of factors; literary betters having more time to work out what might be going on, the time and effort that goes into the research and a good nose for working out where the judges are. A lot of people betting are on the ball with the thinking each year,” said Donohue.

“Despite the fact that people in the market are getting good at guessing, we also get a lot of fans, people who might think that if they keep backing [an author, they] might win. That explains the Bob Dylan movement as well – every year he is towards the top of our list in terms of big payouts. Perhaps it’s like Leicester City – diehard fans dreaming – although we know how that one ended.”

After crunching the numbers since 2005 together with betting data analysis site www.smartbets.com, Ladbrokes said that 91% of the time, the eventual winner of the Nobel has had odds of 10/1 or less at suspension. The betting firm added that on average, the literature winner decreases in odds by 32% during the final week.

Four times, according to the firm, the winner’s odds have fallen dramatically from their opening quote: in 2008, when Le Clézio won, his odds opened at 14/1 and closed at 2/1. In 2009, when Müller won, her odds fell from an opening 50/1 to 3/1; in 2011, Tranströmer’s odds moved from 4/1 up to 12/1 and down to 4/6. Last year, Alexievich’s odds fell from 5/1 to 3/1.

“Of course there are other authors who will shorten in price, and those who will lengthen. However, on only one occasion has there been a significant shortening in odds on an author who hasn’t won: Svetlana Alexievich, who was supported from 50/1 down to 4/5 in 2013. She then went on to win in 2015,” said Ladbrokes.

Donohue added: “The late movements can often be key and a lot of people follow the money at the last minute, meaning you can get a snowball effect.”