Variability & Bias + Article Review

What is the best definition of variability?

• A mistake that makes data unfair

• The natural differences in data values

• The way a question is asked in a survey

• A method for making sure results are accurate

Which of the following is an example of bias?

• Different students reporting different hours of sleep

• Surveying people at random from multiple grade levels

• Only asking your friends what they think about cafeteria food

• Recording the same result from multiple trials

In your own words, explain why variability is expected in real-world data.

What makes bias different from variability?

How could a survey question introduce bias? Give an example.

What was the primary goal of the student council's survey?

• To punish students for using phones

• To find out which apps students use most

• To gather data to support a social media ban during school

• To see how many students have phones

What percentage of survey students admitted to using their phones at least once a day during class?

• 35%

• 64%

• 81%

• 92%

Why might the timing and location of the survey have introduced bias?

• Only freshman were surveyed

• The survey was handed out in classes that encourage phone use

• Teachers collected the surveys unfairly

• Students were forced to answer publicly

Define variability and explain how it appeared in the survey results.

Identify one type of bias in how the survey was conducted. Why does this bias matter?