9/14/2022

Problem session for Activities 5 and 6 will be on Wednesday

Note that for Activity 6 Master has been replaced with People in the Lahman package.
Volunteers will drop their solutions into !Student R Code - Solutions for Activities and Exercises on our Google Drive folder. Please title them Acitivity5-yourname.pdf or Activity6-yourname.R.

Gapminder was created by Hans Rosling in 2005
- Use the googlesheets4 package to show prevalence of HIV and other indicators - see TidyData.R in our Google Drive folder
Short (wide) form versus long (narrow) form of data
Reading different types of data into R
Tidy data
- The rows, called cases of observations, each refer to a specific, unique, and similar sort of thing.
- The columns, called variables, each have the same sort of value recorded for each row.
- Tidy form may not be attractive or appealing, but it is much more useful to an analyst.
Spreadsheets are often NOT in tidy form because they often contain data and summaries/graphs/tables/models/etc.
Suggestions
- Keep your data and analysis separate
- Be able to uniquely identify your cases
- Codebooks may be needed to understand cases and variables
Reshaping data
- Two different formats - wide and narrow
- It is easy to read both formats into R
- pivot_longer() and pivot_wider() allow you to move from one format to another

Step through the R code associated with List-columns in Section 6.2.4 with a peer and make sure that you understand how nest(), pull(), pluck(), and unnest() work.