does a positive correlation indicate a casual link
In statistics, many statistical tests calculate correlations between variables and when two variables are found to be correlated, it is tempting to assume that this shows that one variable causes the other. That ``correlation proves causation,'' is considered a questionable cause logical fallacy when two events occurring together are taken to have established a cause-and-effect relationship. This fallacy is also known as cum hoc ergo propter hoc, Latin for ``with this, therefore because of this,'' and ``false cause.'' A similar fallacy, that an event that followed another was necessarily a consequence of the first event, is the post hoc ergo propter hoc (Latin for ``after this, therefore because of this.'') fallacy.
Correlation does not imply causation