When probability trees don't work

Abstract

Tree diagrams arise naturally in courses on probability at high school or university, even at an elementary level. Often they are used to depict outcomes and associated probabilities from a sequence of games. A subtle issue is whether or not the Markov condition holds in the sequence of games. We present two examples that illustrate the importance of this issue. Suggestions as to how these examples may be used in a classroom are offered.

Keywords:

• Markov condition
• conditional probability
• teaching probability
• simulation

Acknowledgements

We thank Dr Nicole Lazar for encouraging suggestions that assisted us to improve this paper, and the reviewer for a helpful suggestion. Bendigo Health is supported by the Victorian government.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

Bendigo Health is supported by the Victorian government.