How an Ontario statistician cracked Tim Hortons’ digital Roll Up the Rim contest

An Ontario statistician was able to crack Tim Hortons’ Roll Up the Rim contest by winning 98 per cent of his rolls through its loyalty app, after carefully reading the rules and using probability.

Michael Wallace, an assistant professor of statistics and biostatistics at the University of Waterloo, was able to win 94 out of 96 digital rolls during the contest earlier this year, which was forced to be played on the app in an effort to save money and also due to the coronavirus pandemic.

The coffee-and-doughnut chain initially only distributed some physical cups for the contest but removed them altogether in March over concerns around staff handling items that were in customers’ mouths.

Customers received digital rolls and Wallace said he wouldn’t have been able to win big if the company stuck with the physical cups.

“That actually quite significantly changed how the game worked from the player’s perspective in terms of probabilities, because now, whether or not you’ve won was determined when you choose to play those digital rolls,” he said in a phone interview.

The old way was quite simple. Tim’s would print a certain amount of Roll Up cups containing prizes and restaurants would sell the cups until they ran out.

The digital game changed everything and prizes to be won through the app were only made available for a split second, like stopping a slot machine, Wallace said.

According to the official rules, each winning timeframe for any prize was between 0.1 and one seconds.

“You’d win if you played your digital roll and tapped on the app at just the right moment to coincide with one of those prizes,” Wallace said.

This allowed him to exploit the game in a couple of ways, such as playing when fewer others were playing to reduce the chance that someone else would swipe an available prize ahead of him.

He also expected fewer players to be rolling up rims than compared to past years due to its new platform and the pandemic, which meant some prizes that were available for that split second would disappear without anyone claiming them.

The official rules stated those prizes would be re-randomized to a later day in the contest.

Wallace said this made him realize that there was a good chance many of those unclaimed prizes would be available on the final day of the contest.

So after racking up 96 rolls at a cost of just under $40, Wallace set his alarm for 5 a.m. on the final day of the contest in April and started rolling, which he says gave him the maximum possible chance of winning.

“The first one was a winner and I thought, ‘This is a good sign,’ but maybe I just got lucky,” he said. “But then the second one was a winner, and then the third one, and at that point I was pretty sure I was onto something.

“I never really thought it would work until it worked.”

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He ended up winning 67 coffees and 27 doughnuts that morning at a rate of about nine times more than the advertised odds.

Wallace contacted Tim Horton’s about donating his winnings and said they responded well. While they weren’t able to donate his winnings, they did deliver coffee and baked goods to over 400 front-line workers at the Jewish General Hospital in Montreal where Wallace is currently on sabbatical.

He said he’s still trying to donate his own winnings and is in contact with someone who could help donate the winnings to a smaller organization.

“I’m sitting here and I could just start working my way through them but like a lot of people in quarantine, I’m not doing very much exercise,” Wallace joked.

The British ex-pat also joked about sabotaging something so near and dear to the hearts of Canadians, especially while he awaits his Canadian citizenship that he applied for in January.

“There’s been no progress. I’m sure it’s because of the pandemic but there’s a little part of me that thinks ‘gosh this going to come back to bite me,'” he said.

“In my defence, Tim Hortons does the best tea of any kind of fast food place I found in this country.”

1:14 Tim Hortons changes up their iconic Roll Up the Rim

Wallace said he’s not sure if Tim Hortons will move forward with the same format for the next Roll Up contest, but he does have some suggestions if the company is willing to listen.

He also plans to apply this research project to his lectures.

“If telling my students that using statistics I won a bunch of doughnuts doesn’t motivate them, then I don’t know what will,” Wallace said.

In a statement, Tim Hortons confirmed Wallace’s story.

“Professor Wallace was able to capitalize on prizes being rolled over,” the company said. “We were excited when we heard he had read all the rules and used it as an opportunity to teach his students.”