margin of error

A margin of error is the possible difference between a survey's results and what the results would have been if every single person had been included. Any time you make a calculation or take a poll, you need to leave room for mistakes or changes: this is the margin of error.

When a poll is taken, a pollster asks a sample group of people a question. From this smaller representative group, the poll predicts how a much larger group of people would answer: this percentage or number is a guess, and the range of that guess (like, "between 27 and 31 percent of voters dislike this candidate's hair style") is the margin of error. The smaller the margin of error, the more accurate a calculation or statistic is considered to be.

Definitions of margin of error
  1. noun
    the margin required in order to insure safety
    synonyms: margin of safety, safety margin
    see moresee less
    type of:
    an amount beyond the minimum necessary
    a numerical scale used to compare variables with one another or with some reference number
Word Family

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