Can you interpret coefficients in regression analysis output as if they say something about causes of effect. Or is it always about effect of causes? In other words, can a regression analysis answer why-questions or is it always about what-if questions?
Example: Your dependent variable is income in USD (continuous), your independent variables are education (ordinal), sex (dummy) and age (continuous). You fit your OLS model to your data and the output says:
Can you say that because of higher education there is in average higher income while having other IVs constant? Or just if you change education by 1 you get +10 into your income in average while having other IVs constant?