Dependent vs Independent Variables
Dependence and correlation are different. if 2 variables are dependent, then they are correlated. However, if they are correlated, it is not sure that they are dependent, we need domain knowledge to consider more. To check the correlation, we can use the Correlation Coefficient. For the dependence test, we can use the Chi-Square Test.
If I  am given a large data set with many variables is it possible to determine whether any two of them are independent or dependent? Lets assume I know nothing else about the data other than a statistical study.
Would looking at the correlation/covariance be able to determine this?
The purpose of this is to determine which variables would be the best to use in machine learning to predict a specific outcome. I have some variables with a correlation of 0.40 - 0.50 with one another but I'm not sure if a high correlation == dependence.
Thanks