82. In this editorial the author asserts that opinion polls are little better than random
guesses to predicting outcomes of presidential elections. The author's basis for this
assertion is that opinion polls measure only the preferences of voters at the time of the
poll and that many voters change their preferences several time before voting—some
remaining undecided until the moment they cast their vote. The author's reasoning is
unconvincing in two critical respects.
First of alt the predictions based on random guessing are such that the greater the
number of candidates, the less likely the prediction will be correct. The reason for this is
obvious: random guessing requires that no outside information be allowed to influence
the guess. Predictions based on opinion polls, on the other hand, will differ considerably
from those based on random guesses simply because outside information will influence
the result. For example, in a four-person race, random guessing would yield the correct
prediction 25 percent of the time, whereas the percentage of correct predictions based
on opinion polls would be much higher. The reason for this disparity is simple. Opinion
polls enable us to narrow the choices. That is, opinion polls serve to reduce the number
of viable candidates in the voter's mind and thereby increase the likelihood that the
prediction based on them will be correct.
In addition, while it is true that many voters change their minds several times
before voting, and that some remain undecided until entering the voting booth, this is
not true of everyone. Moreover, people who do change their minds frequently or wait
until the last moment to decide have typically narrowed their choice to a few candidates
In conclusion, the author is mistaken in believing that random guessing would be
as reliable as opinion polls in predicting the outcomes of presidential elections.
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