Chess and inteligence corelation

My sister, for her 8th grade project, attempted to solve this problem in the field of spacial reasoning.

She amazingly found that playing chess DID correlate with better spacial reasoning! She almost made it to the national finals with that project.

The problem was that the experiment was flawed to its core: chess players came from a higher income bracket than-non chess players, had access to tools to train their spacial reasoning, and, really, had many different things that differentiated them form their non chess players as a body.

Because of this, it's hard to draw conclusions about the DIRECT correlation and effects of chess on intelligence, as people who play chess are typically, quite frankly, more affluent than people who don't play chess. Playing chess is a luxury given to those who do not have to worry about the security of their housing or the food on their table tomorrow, and those people typically have the luxury of a forma education [this is a generalization ofc]

The bottom line is that correlation is not causation so no real affects can be drawn until a controlled experiment (that would probably be morally sketchy) is done and significance tests performed on the results.

@ChessMathNerd Maybe iq score would resemble intelligence but truly intelligent people score low on purpose. Plus where is your proof that high iq people are drawn to chess?

I think that the chess game helps you to be more creative, more inteligent and why not helps you to socialize with other people too, because you have the emotion relationships. Whose people that play chess are not necessarily inteligent, however they can upgrade it playing and solving puzzles and problems that the game of chess gives. In general, i think that there are people that have more IQ than others who do not play chess, however i think that this was more true in pass, because today there is more ways to meet and play chess, then are much more people playing.
(Sorry for my bad english)

My IQ test result was 100 points (average), and my chess rating is 2000 (better than 95%) . But I passed iq test long time ago, when I was not playing chess.

What about 'Speeling and inteligence corelation' ?

Except for interest in the academic, scientific community for them to have good data. Iq seems like what nobel birt or religious affiliation was. Without interest in the first and need for the latter. Why should a truly intelligent person score high on the test, im sure its better to be underestimated than overestimate. Especially if we doubt the notion that highly intelligent people are more likiely to be peaceful as i recently heard someone say.

I think we should read more about chess history, because I noticed that most of those brilliant chess masters in the past have a higher intelligence. Ex. Paul Morphy- Lawyer, Botvinik- Mathematician.
GM Rosendo Balinas- Lawyer, there are more but I think it's very obvious that chess and intelligence is correlated to each other. I don't know much about Albert Einstein but some says he also plays a good game of chess. (Correct me if I'm wrong)

@Forrestud i bet more idiots play chess than intelligent people, and if you take the ratio of idiots to smart people, it probably will resemble the average population.

Chess and intelligence reminds of the german movie, were a small boy copies everything a tall boy does. Thinking it will make him tall.