4-4 Types of Bias - White Plains Public Schools

SWBAT: Explain how undercoverage, nonresponse, and question wording
can lead to bias in a sample survey.
Lesson 4-4​
Do Now:
An airline that wants to assess customer satisfaction chooses a random sample of 10 of its ​
flights during a single month and asks all of the passengers on those flights to fill out a survey. ​
This is an example of a ​
(a) multistage sample. ​
(b) stratified sample. ​
(c) cluster sample. ​
(d) simple random sample. ​
(e) convenience sample. ​
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Inference for Sampling
The process of drawing conclusions about a population on the basis of sample data. ​
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Margin of Error
Results from random samples come with a margin of error that sets bounds on the size of the ​
likely error. Larger random samples generally have smaller errors than smaller samples. ​
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Sampling Pitfalls
Undercoverage ​ occurs when some groups in the population are left out of the process of ​
choosing the sample. ​
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Nonresponse bias ​ occurs when an individual can’t be contacted or refuses to participate. ​
Response bias ​ is a systemic pattern of incorrect responses. ​
The w
​ ording of questions ​ is the most important influence on the answers given to a sample ​
survey. ​
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SWBAT: Explain how undercoverage, nonresponse, and question wording
can lead to bias in a sample survey.
Lesson 4-4​
YOU TRY!!
1. Each of the following is a source of error in a sample survey. Label each as sampling ​
error or nonsampling error, and e
​ xplain your answers.​ ​
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(a) The telephone directory is used as a sampling frame. ​
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(b) The person cannot be contacted in five calls. ​
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(c) Interviewers choose people walking by on the sidewalk to interview. ​
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2. A survey paid for by makers of disposable diapers found that 84% of the sample opposed ​
banning disposable diapers. Here is the actual question: ​
It is estimated that disposable diapers account for less than 2% of the trash in today’s landfills. ​
In contrast, beverage containers, third-class mail and yard wastes are estimated to account for ​
about 21% of the trash in landfills. Given this, in your opinion, would it be fair to ban disposable ​
diapers? ​
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Explain how the wording of the question could result in bias. Be sure to specify the direction of ​
the bias. ​
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