All possible results or outcomes of a study or experiment define which concept?

• A. Theoretical Probability
• B. Sample Space
• C. Conditional Probability
• D. Joint Probability

Answer: (B)

The set of all possible results of an experiment is called the sample space. This is the complete universe from which probabilities are drawn and to which every outcome belongs. For example, rolling a six-sided die has a sample space of {1, 2, 3, 4, 5, 6}; flipping a coin has a sample space of {Heads, Tails}. Events are subsets of this space, like the event “an even number” which corresponds to {2, 4, 6}. The idea here is that probabilities are assigned to these events within the framework of the sample space.

The other terms describe different ways we work with these outcomes: theoretical probability is the method or model used to calculate probabilities, conditional probability is the probability of an outcome given that another event has occurred, and joint probability is the probability of two events happening together. They’re all about assigning or relating probabilities, whereas the sample space is about listing all possible outcomes themselves.