Jul 14 2011

The Money or the Box

You are a contestant on ‘Pick A Box’, and have won your way through to the final round.

“As our champion of the night, you get the chance to win our major prize – a brand new Holden!  Pick a door, and the prize behind it is yours” says the host, Bob Dyer.

There are three doors – behind one of them is a car, and behind each of the other two doors is a goat.

The organs plays some thinking music, the audience call out suggestions, and you pick door number 1.

Bob is a pro, and knows how to build suspense. “Our champ has picked door number 1. Dolly, let’s see what he would have won if had picked door number 3”, he says.

The room is silent. Bob’s glamorous assistant Dolly slides opens Door Number 3. The audience gasps. A goat stands quietly behind it, chewing it’s cud.

(Bob knows what’s behind all the door. Every night he opens another door, and every night it reveals a goat)

“Now champ”, says Bob. “You have a choice. You can stick with your original selection, or change to Door Number 2. What’ll it be – stick or change”

What should you do? Which option gives you the best chance of winning – switching, staying, or is it 50:50 whatever you do.

This ‘Monty Hall Problem’ was first posed by Steven Selvin in 1975, and received widespread publicity when it featured in Parade Magazine in 1990. (Monty Hall was the original host of the US “Let’s Make a Deal”. He was therefore their version of our own Bob Dyer)

Here’s a clue. The correct answer is famously counter-intuitive. 90% of people answer incorrectly. 10000 people wrote to Parade magazine saying that the author of the article had made a mistake, and 1000 of these had a PhD. Yet the solution is simple.

One of the options gives double the chance of the other!

When you’re ready to decide, read the explanation on Wikipedia.

http://en.wikipedia.org/wiki/Monty_Hall_problem

The Sydney University Football Club Puzzle is a variation on the Monty Hall Problem, but remains unexplained by mathematicians and scientists. Australia’s oldest Rugby club has been raffling the same bottle of Scotch at home games for at least 30 years, and possibly since the formation of the club in 1863. Yet despite the hundreds of tickets that are sold every week, no one ever seems to hold the winning number. Perhaps the current custodian of the bottle, Andrew C, can explain this mystery.

Pick-A-Box started on Sydney radio 2GB in 1948, and made the transition to television in 1957. It was a stalwart of Australian viewing until 1971!

I’ve always wondered why Barry Jones became famous as a contestant on the show. It turns out that he was more than just a contestant – he won 208 episodes between 1960 and 1967! Of course, he went on to become a minister in the Hawke government and president of the Australian Labor Party.

You can watch Episode 170, featuring Barry Jones, in the Australian screen archives

Take the money, Barry