Unbiased and objective data

Data bias

• A type of error that systematically skews results in a certain direction

Sampling bias

• A sample that isn't representative of the population as a whole

Unbiased sampling

• A sample that's representative of the population being measured

Question

An unbiased sample is representative of the population being measured. Which of the following helps ensure unbiased sampling?

• Storing data in a spreadsheet
• Writing survey questions that encourage specific responses
• Using random sampling during data collection
• Skewing results in a certain direction

Correct. Using random sampling during data collection helps ensure unbiased sampling.

More types of data bias

• Observer bias (experimenter bias / research bias): The tendency for different people to observe things differently
• Interpretation bias: The tendency to always interpret ambiguous situations in a positive or negative way
• Confirmation bias: The tendency to search for or interpret information in a way that confirms pre-existing beliefs

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Test your knowledge on unbiased and objective data

TOTAL POINTS 3

Question 1

Which of the following are examples of sampling bias? Select all that apply.

• An online marketing analytics firm stores data in a spreadsheet.
• A survey of high-school-age students does not include homeschooled students.
• A clinical study includes three times more men than women.
• A national election poll only interviews people with college degrees.

Correct. A survey of high-school-age students that does not include homeschooled students, a national election poll that only interviews people with college degrees, and a clinical study that includes three times more men than women are not representative of the population.

Question 2

Fill in the blank: The tendency to search for or interpret information in a way that validates pre-existing beliefs is _____ bias.

• observer
• interpretation
• sampling
• confirmation

Correct. The tendency to search for or interpret information in a way that validates pre-existing beliefs is confirmation bias.

Question 3

Which of the following terms are also ways of describing observer bias? Select all that apply.

• Perception bias
• Research bias
• Experimenter bias
• Spectator bias

Correct. Observer bias is sometimes referred to as experimenter bias or research bias.

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Explore data credibility

Identifying good data sources

• Reliable
• Original
• Comprehensive
• Current
• Cited

Test your knowledge on data credibility

TOTAL POINTS 3

Question 1

Which of the following are usually good data sources? Select all that apply.

• Academic papers
• Vetted public datasets
• Social media sites
• Governmental agency data

Correct. Vetted public datasets, academic papers, and governmental agency data are usually good data sources.

Question 2

To determine if a data source is cited, you should ask which of the following questions? Select all that apply.

• Who created this dataset?
• Has this dataset been properly cleaned?
• Is this dataset from a credible organization?
• Is the data relevant to the problem I’m trying to solve?

Correct

“Is this dataset from a credible organization?” and “Who created this dataset?” are questions that can help you determine if a data source is cited.

Question 3

A data analyst is analyzing sales data for the newest version of a product. They use third-party data about an older version of the product. For what reasons is this inappropriate for their analysis? Select all that apply.

• The data is not accurate
• The data is biased
• The data is not current
• The data is not original

Correct. Third-party data about an older version of the product is inappropriate because it is not original or current.