correlation vs. causation

Correlation indicates the direction (+/-) and degree of relationship between two random variables, and does not necessarily indicate a cause-effect relationship (causation). That is, correlation does not imply causation.

For example, if a group of people are wearing lightweight clothing and perspiring, this positive correlation does not indicate that lightweight clothing causes people to perspire. On the other hand, a correlation between strenuous exercise and perspiration is associated with causation.

Quo Vadis?
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