3.2.1.Unbiased and objective data & Explore data credibility - sj50179/Google-Data-Analytics-Professional-Certificate GitHub Wiki
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 spreadsheetWriting 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
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.
observerinterpretationsampling- 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.
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 accurateThe 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.