Page 3 - FINAL CFA I SLIDES JUNE 2019 DAY 3
P. 3
Session Unit 2:
9. Probability Concepts
LOS 9.a:
Define a random variable, an outcome, an event, mutually exclusive events, and exhaustive events, p170.
• A random variable is an uncertain quantity/number
e.g. X = 1 or 2…or 6 of a fair die you roll!
• An event e.g. the actual rolling of the die!
• An outcome is an observed value of a random variable
e.g. the no. say 4, that appears!
• Mutually exclusive events are events that cannot both happen at the same time. e.g. you can’t in
one event/roll, get a 1 and a 2!
• Exhaustive events are those that include all possible outcomes e.g. die roll can be ONLY odd or even, so
combined, these 2 outcomes are mutually exclusive and exhaustive!