Big Ideas Math Algebra 2, 2014
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Big Ideas Math Algebra 2, 2014 View details
5. Making Inferences from Sample Surveys
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Exercise 22 Page 632

If sample data has a large standard deviation, then the margin of error is also large.

See solution.

Practice makes perfect

Let's begin by recalling that the margin of error tells us about a limit on how much the responses of the sample would be different from the responses of the whole population. Having this in mind, let's take a look at the given graph that presents the sample proportions from 3 simulations.

Looking at the graph, we can see that sample a has the least standard deviation σ because its distribution is the most narrow. On the other hand, the distribution of sample c has the most wide distribution, so this sample has the largest standard deviation. σ_a<σ_b<σ_c When sample data values differ from each other a lot, we can suspect that the responses of the sample can also differ a lot from the responses of the population. Therefore, samples with the greatest standard deviations will have the greatest margins of error ME. σ_a<σ_b<σ_c ⇓ ME_a