# Econometric Theory/Statistical Inference

Statistical inference is the attempt of making a statement about a population using only sample data that is a subset of that population. This is necessary since in most situations it is either impractical or expensive (or both) to collect data on the whole population.

Statistical inference is broken up into the following parts:

- Identification of the problem.
- Identification of the population.
- Specification of the statistical properties of the parameters in question.