Chance, Choice, and Consequence

“Excellence is never an accident. It is always the result of high intention, sincere effort, and intelligent execution; it represents the wise choice of many alternatives – choice, not chance, determines your destiny.” — Aristotle

Chance, Choice and Consequence

• This SUTD module features the "Who Am I?" Game based on the classic "Guess Who" Game by Hasbro. It is designed to to illustrate basic concepts in probability. It is part of a workshop we run which focuses on applications of Conditional Probability.

The "Who Am I?" Game

• This game helps you to perceive probabilities in terms of sets of features.
• The "chance" is a randomly-drawn mystery card with the identity of one of the characters hidden.
• The "choices" are what questions you ask to eliminate characters from consideration, based on their features. By a process of elimination you can identify the mystery character.
• The "consequences" are the number of questions it takes for you to identify the character. This is your score. You can be lucky or unlucky but, if you play multiple times, it is your skill at choosing the right questions that determines how well you do in the long run.

How to Play

Are You Ready to Play?

• (Game appears on the next slide)

Is the Screen Too Small?

• The circles are not meant to be overlapping like this:

Is the Screen Too Small?

• Try switching your browser to full screen so it looks like this:

Advanced Play

• You can do better at the "Who Am I?" Game by asking more sophisticated questions. These are questions like "Does the mystery character have brown hair but no beard?
• Select the feature "Has Brown Hair", and then click "SUPPOSE YES". All the people without brown hair are excluded from subsequent probability calculations.
• Next, select the feature "Has Beard" but this time click "SUPPOSE NO". All the people with beards are excluded.
• Now click "ASK THE QUESTION". If the mystery character matches the supposed features then all characters who do not match the supposed features are eliminated. On the other hand, if the mystery character does not match those features, then all characters who do match the combination of features are eliminated.

Are You Ready to Play?

• (Advanced game appears on the next slide)

What Are Those Probabilities?

• We compute some useful probabilities for you:

How Is That Useful?

• With one question you can eliminate 50% of the characters:

Some Questions Don't Make Sense

• If you ask a question we can't answer we allow you to clear one of your selections:

Play With Your Friends

• Now play the game with your friends and keep track of your average score.
• Remember: you can be lucky or unlucky in any one game, but in the long run it is your skill at weighing probabilities that will win the day!


• And remember your winning strategy the next time you are in a situation where your decisions will reveal information, such as:
• Choosing tests to diagnose your patient's illness;
• Checking suspects' alibis after a crime;
• Finding a reliable source of supply for a critical raw material...

Learn More

• We hope you enjoyed this module and would like to learn more about applications of probability and optimisation.
• Please visit our website at SUTD Engineering Systems and Design