Census

This packet introduces the following terms:

•  Census - sampling every possible unit in a population
•  U.S. Census - a census performed every 10 years by the U.S. government to get an accurate picture of our population.

In theory, it seems ideal to take a census. There is no guessing, every single unit is sampled. So this should be done every time right?

Wrong! The reality is that it is usually not cost effective, time effective, or even possible to get a complete census. The U.S. government conducts a census every 10 years, but even that is not a true census, since a lot of people do not respond, and are therefore not included in the results.

Statistics was born out of the reality that you can't reach every unit in a population. So using samples to make inferences, or educated guesses, about the population became a very cost effective and efficient thing to do.

You can say that a census is ideal, but statistics is real.