Intro to Tournament Graphs | Graph Theory

We introduce directed tournament graphs, which can be thought of as a graph representing the outcome of a round robin tournament - where vertices represent teams, and directed edges (arcs) go from winners to losers. We'll also discuss how many labelled tournaments there are on n vertices, and how many unlabelled tournaments there are. #GraphTheory

We see several explanations and examples of tournament graphs, and some non-examples. A tournament is a directed graph with exactly one arc between each pair of vertices. Or equivalently, it is an orientation of a complete graph.

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[WrathofMath]

CORRECTION: Around 8:40 I show the only two tournaments with n=3. The tournaments shown are isomorphic by mistake. The two tournaments with n=3 are the cycle graph C3 (not depicted by mistake) and the graph I accidentally drew twice.

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[PunmasterSTP]

I've come across some graph theory over the years, but I don't ever recall learning the term "tournament graph". Cool stuff!

[EHTFS]

Great video! This helped me a ton with my discrete mathematics class. Can't believe it doesn't have more views!

[peterburbery]

Can you make some videos on graph types?
This is really helpful explanation.
For example, maybe a video covering sunlet graphs, gear graphs, etc.

[JurgenN-cust]

There is a mistake in the example for the non-isomorphic tournaments: in the case n=3, the depicted graphs are actually isomorphic.

[oiciruamlau]

Lol you scared me when you said the last eg the k4 was not a tournament