In the recent French primary election for president, the last pre-election poll
ID: 3240376 • Letter: I
Question
In the recent French primary election for president, the last pre-election poll was : Macron = 24.0% Le Pen = 22.5% Fillon = 19.5% Melenchon = 18.5% Others = 15.5% The final primary election results were: Macron = 23.8% Le Pen = 21.6% Fillon = 19.5% Melenchon = 19.0% Others = 16.1% One of constant things you hear about election polls in the US is that the margin of error is +/- 3%. In France, the standard margin of error is 1.6%. Obviously, if the margin of error is too large, the poll is of no use. For example, in almost all elections where there are 2 major candidates, the winner gets 50% +/- 10% of the vote.
(a) So for this pre-election poll, did all of the predictions all fall within the margin of error of +/- 1.6%? (yes or no). If you answered “no”, then what should the pollster have said the margin of error was in order for all of the predictions to be correct?
(b) Why do you think the standard American margin of error is +/- 3% while the standard French margin of error is +/- 1.6%?
Explanation / Answer
Ans:
All are not within margin of +/-1.6%
So,pollster should have said the margin of error is +/- 4% ,because largest margin of error is 4% in pre-poll.
b)Larger margin of error cause lesser error in prediction of pollster,so they might have set larger margin of error
Pre-Poll Primary poll % margin 24 23.8 0.833333 22.5 21.6 4 19.5 19.5 0 18.5 19 -2.7027 15.5 16.1 -3.87097