‘Not impossible’: Statistical probability of 433 bettors winning 6/55 Grand Lotto jackpot

October 3, 2022 - 1:31 PM
Individuals bought lotto tickets at a lotto outlet in Quezon City on Sunday (September 2, 2022). (The STAR/Michael Varcas)

Some data analysts believed that it is possible for 433 bettors to win last Saturday’s lottery prize.

On October 1, the Philippine Charity Sweepstakes Office (PCSO) announced that these bettors won the P236-million 6/55 Grand Lotto jackpot.

They will split the jackpot money and receive around P500,000 each.

The winning six-digit combination is 09-45-36-27-18-54.

This was considered a historic and unusual draw by some people given the odds of the number of winners getting the combination.

They also ran speculations around the combination consisting of multiples of nine.

The Livestream where the numbers were drawn could still be viewed on PCSO’s Facebook page.

The office also uploaded a graphic that showed the rest of the draw results for that day.

Statistical probability

University of the Philippines statistician Peter Cayton said that the statistical probability of 433 people winning a 6/55 lottery is small but not impossible.

In a Twitter thread on October 2, Cayton explained that the odds would be one in 28,989,675.

“If I was given incomplete context, and someone asks me ‘what is the chance 433 people would win the jackpot of the 6/55 lotto?’ It’s not impossible, because we already saw it happen!” Cayton said.

“But how would I quantify the chance…approximately, it would be (1/28,989,675)^433,” he added.

The probability changes when human behavior is factored in.

Cayton pointed out that humans naturally have a preference for number patterns such as the winning combination.

“But, if you showed me the winning ticket as 09-18-27-36-45-54 THIS IS SUCH A HUMAN THING TO DO! Humans have preferences with patterns of order for many reasons,” Cayton said.

“Certain combinations are chosen more often than others, especially if it’s a choice one would follow religiously or by convenience. It’s just human of us to do things beyond the rules of nature and to make order out of chaos, for whatever simple reason we have,” he added.

OCTA Research fellow and data scientist Guido David also mentioned the low probability of 433 6-5 winners. He said the combination could also mean many are betting on the numbers divisible by 9.

“People want to know the probability of 433 6-55 winners. It is 1 to 1.87e-1224. That is 1 out of 1 followed by 1224 zeros. The age of the universe is 4.3e17 seconds (17 zeros). However, the winning combination, divisible by 9, could mean more people bet on it,” he wrote in a tweet.

Edson Guido, ABS-CBN’s resident data analyst, also said that the chances of such results are low but can still happen.

“To get the 6 winning digits out of 55, that’s 1 out of 28,989,675… or 0.000003% Grabe diba? Tapos 433 nakakuha. What’s the winning combination? 9-18-27-36-45-54 Multiples of 9 LOL,” he said.

Guido was amused that 433 winners will now have to split the prize.

“The 433 winners will split the jackpot prize of ₱236,091,188.40 or ₱545,245.24 each. From 236 million to 545 thousand hahahahahaha mahirap talaga mabuhay ng may kahati,” he said with a laugh emoji.

Several Filipinos, however, found the 433 winners and the winning lotto combination suspicious.

Former senator Panfilo “Ping” Lacson said that he would look for a “common denominator” among the winners if he were to investigate it.

“433 winners in one 6/55 lotto draw is highly improbable, if not impossible. If I were to investigate this apparent PCSO anomaly, I’d start by looking for a common denominator of these ‘lucky ones’,” Lacson tweeted.

A TikTok creator named “raspberrypiii,” meanwhile, released a video that detailed how improbable the situation is. He also noted that he does not believe this can happen.

@raspberrypiii Kaso ika nga nila improbable but not impossible. But i dont buy it #lotto #433 #electricalengineering #statistics ♬ original sound – howarddelosreyes on ig

The two minority senators Aquilino “Koko” Pimentel III and Risa Hontiveros are seeking to investigate PCSO over such results.

In a radio interview, Pimentel said that the purpose of the proposed probe is to “ensure the integrity” of the gambling games.

“Supposed to be, your chances of winning is one in millions. So that means it’s really difficult to win. To say that 433 people won, there is something suspicious,” Pimentel was quoted in the report as saying.