Dealing with insufficient data

If you have to complete your analysis with insufficient data, how should you address this limitation?

A. Create new datasets similar to what’s available

B. Use only the data that supports their desired outcome

C. Estimate certain findings based on your best guess

D. Identify trends with the available data

The correct answer is D. Identify trends with the available data

The importance of sample size

What are some of the possible challenges associated with using 100% of a population in data analysis? Select all that apply.

• Using 100% of a population is unreliable.
• Using 100% of a population is time-consuming.
• Using 100% of a population is expensive.
• Using 100% of a population is not representative.

Explain: Using 100% of a population is time-consuming and expensive.

Companies usually create sample sizes before analysts get to see the data. True or False?

A. True

B. False

It is true statement. Explain: Companies usually create sample sizes before data analysis so analysts know that the resulting dataset is representative of a population.

Using statistical power

Which statistical power is typically considered the minimum for statistical significance?

A. 0.8 or 80%

B. 0.5 or 50%

C. 0.9 or 90%

D. 0.6 or 60%

The correct answer is A. 0.8 or 80%. Explain: A 0.8 or 80% statistical power is typically considered the minimum for statistical significance.

A Gentle Introduction to Statistical Power and Power Analysis in Python sums it up nicely:

"Statistical power can be calculated and reported for a completed experiment to comment on the confidence one might have in the conclusions drawn from the results of the study. It can also be used as a tool to estimate the number of observations or sample size required in order to detect an effect in an experiment."

Optional: If you want a more detailed explanation of statistical power and power analysis, the above link is a tutorial that also lists additional references.

Determine the best sample size

To use the sample size calculator spreadsheet, click the link below and select “Use Template.”

Link to template: Sample Size Calculator

OR

If you don’t have a Google account, you can download the spreadsheet directly from the attachment below.

Fill in the blank: When calculating sample size using an online calculator, it’s necessary to input the _____. Select all that apply.

• margin of error
• statistical power
• confidence level
• population size

Explain: To calculate sample size using an online calculator, it’s necessary to input the confidence level, margin of error, and population size.

Evaluate the reliability of your data

To calculate the margin of error in the same spreadsheet as the instructor, click the link below and select "Use Template." You can try entering different values to see how the margin of error changes.

Link to template: Margin of Error Calculator

OR

If you don't have a Google account, you can download the spreadsheet in the attachment below