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The Three Doors of Serendip Applet 2

If you didn't get here through The Three Doors of Serendip exhibit you may want to go there first.


start new game clears your current winnings and all playing history, while play again starts a new trial within a game, without clearing any winnings.

1) First choose a door by clicking on the numbered button (#1, #2, or #3) on any of the three doors. Your selection will be highlighted with two arrows.
2) Serendip will then open a different door to show you that the prize is not there. You are then given the chance to stay with your current door, or switch to the other remaining, unopened door. Click on either the stay or switch button.
3) Serendip then opens the door you've chosen and you either win (Serendip's logo) or lose (sad face). 4) To continue playing, click play again.
5) Use the auto-play: random, auto-play: stay every trial, and auto-play: switch every trial buttons to let the game run by itself. To stop auto-play click the appropriate button again.

- Your total trials and wins are displayed in the times played and wins monitor.

- The % wins of each strategy monitor plots the wins for all trials for which you've stayed and all trials for which you've switched.


Posted by Laura Cyckowski and Paul Grobstein on 19 August 2008. Applet created using NetLogo, the availability of which is gratefully acknowledged.







Daniel's picture


I believe you should switch in every turn, and also that contrary to some suggestions the previous door which had the prize does not matter.

I've used the auto play buttons and obtained the following;

Auto-play: Switch every trial Played 2462, won 1644, win% 67%
Auto-play: Stay every trial Played 2818 won 956 win% 34%
Auto-play: Random Played 2620 won 1286 win% 49%

Mighty Cammor's picture

Switching ain't Snitching

Well, switching EACH time seems to grant a 75% win. Making the switch is the way to go. Why? Because the clue is helping you see which one is NOT correct and the odds that the one you picked right of the bat being correct is not too great (1 in 3 odds). So, switching would then give you a 1 in 2 chance rather than 1 in 3. The logic hurts my brain but it works.

Serendip Visitor's picture

I conclude that once you find

I conclude that once you find the door with the logo behind it the first time , you remembe which door hd the logo behind it and selec it in the next ame, then when it asks you to stay or switch you switch and that should be the new door with the logo behind it. but on every third or 4th time it will not work qite like this, you will have to stay.. i think

Jason Johnson's picture

To: Serendip Visitor - You

To: Serendip Visitor - You are correct. Once you Get the Blue-Meany you choose the door that held the "X" Previously, and then choose switch.
And it will put you back on track. Fallow that path the victory. It was more fun playing for Money, rather than a symbol with no name. 80)

Anonymous's picture

I seem to be much better at

I seem to be much better at this level than the first. Maybe my cat really is training me!

Anonymous's picture

the only thing i can conclude

the only thing i can conclude from this is that you have a better chance by doing it different each go

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