How is it that in the U.S.,surveys of 1,000 are accepted as representative of the entire country?

Question

I’ve noticed most U.S. polls query around 1,000 people and sometimes even less. Somehow that qualifies for headlines like “Americans say…” or “Most Americans…” How is it acceptable that 0.0002% of the population is accepted as representative?

In: Other

Answer 1

I’ve been citing this piece for years: [How can a poll of only 1,004 Americans represent 260 million people with only a 3 percent margin of error?](https://www.scientificamerican.com/article/howcan-a-poll-of-only-100/)

“The margin of error depends inversely on the square root of the sample size. That is, a sample of 250 will give you a 6 percent margin of error and a sample size of 100 will give you a 10 percent margin of error.” It doesn’t matter how many people the survey represents, because as long as the sample is truly random/representative (as other commenters have explained), the *percentages* will stays the same.

One bag of M&Ms will (within margin of error) have the same percentage of blues as a million bags of M&Ms all dumped into a bowl together.