Oversampling of one group or another is a danger of any polls. But the goal of all of them is to be accurate.
Link: http://projects.fivethirtyeight.com/pollster-ratings/
Oversampling of one group or another is a danger of any polls. But the goal of all of them is to be accurate.
Link: http://projects.fivethirtyeight.com/pollster-ratings/