A newspaper article about an opinion poll says that 43 of Am

A newspaper article about an opinion poll says that \"43% of Americans approve of the president\'s overall job performance.\" Toward the end of the article, you read: \"The poll is based on telephone interviews with 1210 adults from around the United States, excluding Alaska and Hawaii.\" Which of the following could be possible sources of bias in the sampling method used?

Select one or more:

1. A sample of 1210 is too small to represent all Americans.

2. Some people responding to the survey may not be registered voters.

3. People without telephones were not included.

4. If researchers had initially contacted 3000 adults, but only 1210 responded.

Solution

It is given The poll is based on telephone interviews with 1210 adults from around the United States, excluding Alaska and Hawaii. So People without telephones were not included. would be correct... even , A sample of 1210 is too small to represent all Americans. can also be correct.