Limitations of census?

Question

applied demography

Answer 1

1)  Only covers those with a residence.  So the homeless, travelers, and regularly nomadic are falsely reported.

2) Entirely voluntary, so lazy people and liars it doesn't always give true results.

3)  Like IRS figures, illegal populations go unrecorded.

Answer 2

We need more information to answer this question. It's not even a complete sentence. I'd suggest trying a little harder next time you want other people to do your homework for you.