To prepare for this Discussion, consider the following scenario:
Polls will often present candidates running for election as winning or losing based on the results of recent surveys. When presenting the poll, there is usually information about a “margin of error.” What does that mean?
For example, consider that one survey, conducted by a professional polling organization, shows Candidate Q with 49% with a plus or minus margin of error of 2 percentage points (usually depicted as ±2%). The same survey shows the other candidate, Candidate Z having an estimated 47% of likely voters and the same margin for error (±2%).
However, consider that another survey taken of the same population in the same day by a different professional polling organization has different results. In this survey, Candidate Z has polled at 49% while Candidate Q, has only polled at 46%. This survey has a 3-percentage-point margin of error (±3%).