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Do you have any evidence that tennis skill is normally distributed?

im3w1l 8y ago
The question whether it's normal distributed doesn't even make sense. Tennis skill and intelligence are both Ordinal Scales. IQ is normal but that is just because we take everyones intelligences and assign them to a value from a normal distribution. http://www.mymarketresearchmethods.com/types-of-data-nominal-ordinal-interval-ratio/ http://www.mymarketresearchmethods.com/types-of-data-nominal...
- tpeo 8y ago
  What do you mean by an ordinal scale, and what does that imply? I'm completely blind on this usage of the expression.
  - paulddraper 8y ago
    It means that values are ordered, but not really numbers. E.g. what does 2x better tennis skill mean? An under that idea, the distribution curve doesn't really mean anything.
    - tpeo 8y ago
      It would mean what this particular variable has been operationalized [0] to mean. Once upon a time things such as "heat" were just words, and as words they were used in a variety of different implicit senses in which at the time people didn't distinguish -- for whatever reason -- but that people thought that nonetheless were informative about the thing in question. Which is to say that words were used as heuristics, partly as reasonable descriptions, partly as expressions of gut feelings. With the association of heat with thermal expansion and the development of better apparatuses (e.g. the ordinary mercury column thermometers) as well as the diffusion of this concept among laymen though stuff such as weather prediction, it became the most salient form of "heat", and thus the standard use of the word when unqualified came to mean just that: what a thermometer reads. But other forms of heat i.e. the personal feelings of heat associated with climatic comfort, or the action of capsaicin or even wounds -- and this is the origin of the word "inflammation" -- came to be used only when qualified. These are all said to be "subjective heat". Now, I can only claim that all that I've said is merely opinion, since I haven't quite yet worked out to properly cite just who might have said this prior to me and for what reasons -- and which I currently wont, because it's scattered over stuff and I don't know even how to begin -- so this is all provided as is. About ordinality, as opposed to cardinality, I can only say that I didn't see the connection at the beginning, but now that I've thought a little while about it, it does seem like a philosophically uncomfortable idea. But I'm not going to be the one to say why, at least not now. [0]: https://en.wikipedia.org/wiki/Operationalization https://en.wikipedia.org/wiki/Operationalization
barry-cotter 8y ago
It would be very strange if tennis skill was normally distributed. More than likely it’s a power law. Reaction time, physical strength and speed are normally distributed. The product of them will be approximately exponential. That’s almost certainly a better approximation of tennis skill. Ditto for likelihood to get rich. Intelligence, conscientiousness and luck for those. Luck is obviously an enormous factor in accumulating wealth. You’re a great deal more likely to get wealthy in the US than in Botswana and where you’re born and who you’re born to are luck.
whack 8y ago
You would see the same abnormally-distributed-outcomes in any winner-takes-all game where skill is normally distributed, and the higher-skilled-player always wins. The fact that skill is normally distributed but outcomes aren't, doesn't imply in any way that it's due to randomness. In fact, the less random the game is, the more abnormal its outcome-distribution would be - the best player would win every single championship despite being just slightly better than the others.

The question whether it's normal distributed doesn't even make sense. Tennis skill and intelligence are both Ordinal Scales. IQ is normal but that is just because we take everyones intelligences and assign them to a value from a normal distribution. http://www.mymarketresearchmethods.com/types-of-data-nominal-ordinal-interval-ratio/ http://www.mymarketresearchmethods.com/types-of-data-nominal...

tpeo 8y ago
What do you mean by an ordinal scale, and what does that imply? I'm completely blind on this usage of the expression.
- paulddraper 8y ago
  It means that values are ordered, but not really numbers. E.g. what does 2x better tennis skill mean? An under that idea, the distribution curve doesn't really mean anything.
  - tpeo 8y ago
    It would mean what this particular variable has been operationalized [0] to mean. Once upon a time things such as "heat" were just words, and as words they were used in a variety of different implicit senses in which at the time people didn't distinguish -- for whatever reason -- but that people thought that nonetheless were informative about the thing in question. Which is to say that words were used as heuristics, partly as reasonable descriptions, partly as expressions of gut feelings. With the association of heat with thermal expansion and the development of better apparatuses (e.g. the ordinary mercury column thermometers) as well as the diffusion of this concept among laymen though stuff such as weather prediction, it became the most salient form of "heat", and thus the standard use of the word when unqualified came to mean just that: what a thermometer reads. But other forms of heat i.e. the personal feelings of heat associated with climatic comfort, or the action of capsaicin or even wounds -- and this is the origin of the word "inflammation" -- came to be used only when qualified. These are all said to be "subjective heat". Now, I can only claim that all that I've said is merely opinion, since I haven't quite yet worked out to properly cite just who might have said this prior to me and for what reasons -- and which I currently wont, because it's scattered over stuff and I don't know even how to begin -- so this is all provided as is. About ordinality, as opposed to cardinality, I can only say that I didn't see the connection at the beginning, but now that I've thought a little while about it, it does seem like a philosophically uncomfortable idea. But I'm not going to be the one to say why, at least not now. [0]: https://en.wikipedia.org/wiki/Operationalization https://en.wikipedia.org/wiki/Operationalization

barry-cotter 8y ago

It would be very strange if tennis skill was normally distributed. More than likely it’s a power law. Reaction time, physical strength and speed are normally distributed. The product of them will be approximately exponential. That’s almost certainly a better approximation of tennis skill. Ditto for likelihood to get rich. Intelligence, conscientiousness and luck for those. Luck is obviously an enormous factor in accumulating wealth. You’re a great deal more likely to get wealthy in the US than in Botswana and where you’re born and who you’re born to are luck.

whack 8y ago

You would see the same abnormally-distributed-outcomes in any winner-takes-all game where skill is normally distributed, and the higher-skilled-player always wins. The fact that skill is normally distributed but outcomes aren't, doesn't imply in any way that it's due to randomness. In fact, the less random the game is, the more abnormal its outcome-distribution would be - the best player would win every single championship despite being just slightly better than the others.