Poker: Luck vs Skill

For as long as I've been playing poker, I've obviously been on the side of the game being skill based. However, after thinking about it over the past week, I think it's much more cut and dried than simply being based on skill or being majority skill. It's 100% skill. Exactly like chess. There is no luck involved. Here's why:

You'll often find poker players that try to attribute arbitrary ratios of skill and luck to games as if they are on the same gradient scale. Poker being 70/30 for example, blackjack being 40/60 etc.

• Luck: Success or failure apparently brought by chance rather than through one's own actions.
• Skill: The ability to do something well; expertise.

People will generally try to play semantic gymnastics in trying to quantify a balance of opposing definitions. I find it to be a contradiction of each definition for something to involve both skill and luck, especially when the "luck" disappears in large samples. Perhaps a more apt definition would be the term "chance" already used in the definition of luck.

• Chance: by accident or without design.

We've all heard the term "games of chance" and are quick to rightly interchange it with the term "luck." When it comes to games seemingly involving both, this term clearly does not allow for that to happen. In games of skill, every action you and your opponents make has a direct effect on everyone's expected value.

In games of chance, no action that you or your opponent can make has any effect on anyone's expected value. Skill and chance can not occupy a gradient balance with one another.In theory then, every single decision at the poker table is 100% skill based. In theory, there is only EV, there are no results. Now you're probably thinking "a ha! It doesn't work that way in practice!" and you'd be correct. In practice, our results deviate from our expected value. That deviation is called "variance."

• Variance: The fact or quality of being different, divergent, or inconsistent.

Variance is not luck.

The terms are, by definition, not interchangeable. Variance is simply the measured, quantifiable difference between EV and results. It has nothing to do with your ability or inability to affect the outcome. You shove $100 with AA and get called by KK for 80% equity and an EV of about $60. You are either going to be +$40 or -$60 on expectation for any given hand due to not luck, but rather variance. 

• Poker is 100% skill with variance in the results.

Now take the opposite type of game, lets say slots. You put $1 in and pull the lever, with absolutely no skill on your part affecting the outcome. Your EV on any given pull is -$0.05 on this particular machine. You are most definitely not going to receive exactly $0.95 back on your dollar with every pull. The difference from your EV is, again, variance. 

• Slots are 100% luck with variance in the results.

Therefore, all things where a calculable EV is available are either all skill or all luck with a measurable amount of deviation that can be used to statistically compute how much fortune appears to play a part.

• Fortune: Chance or luck as an external, arbitrary force.

Fortune is the word and concept people are looking for when they are trying to mistakenly apply a luck:skill ratio by virtue of interchanging false definitions of luck and variance in a game of skill that has deviation in the results.

The idea of fortune is the mirage that keeps recreational players entertained despite their inevitable losses. Which brings us full circle to a point where poker is indeed 100% skill, with the veneer of luck, ie. fortune, entering the equation and creating a non-existent luck:skill ratio draped over the game due to the psychological effects of variance.