30pts) Consider the following sets of potential dependent and main independent variables:

Dependent	Independent
Weight at birth	Smoking
Crime Rate	Expenditure on Police Services
Health Outcomes	Health Insurance
Earnings	Private (vs public) school education
Smoking	Cigarettes prices
Employment	Immigration
School Performance	Class Size
Employment	Mega-Events (Olympics or World Cups)

For two of these cases and explain:

Why would the independent variable would have a causal effect on the dependent variable.

Is there a design or scenario you can think of that would enable to identify the causal effect?

What other factors should be considered when estimating the econometric model, in order to identify causal effect. Why?

Which ones of these factors may also be related to the independent variable? What are the consequences of not including them in your model specification