What should each column hold? What should each row hold?
Flip the card by pressing the q key.
How many pieces of information belong in a single cell?
1
A spreadsheet marks uncertain measurements by coloring the cells.
Why is this a problem, and what should be done instead?
Computers can’t easily read color, fonts, or italics as data.
Put the information in its own column.
What is wrong with the column name body mass (g)?
Spaces and special characters like ( ) @ * ^ mean special things to computers.
Use snake_case (body_mass_g) or CamelCase (bodyMassG) instead.
When two rules for naming things in a data set?
A dataset has missing masses written as -999.
What should you use instead?
A good null value like NA.
-999 is a number, so it will silently end up in means and plots.
What format should you use for dates?
YYYY-MM-DD (the ISO standard)
A table repeats the site name, latitude, and longitude on all 5000 rows.
What is the tidy fix?
Use one table for each category of data.
Create a separate site table and link it to the survey table using a shared column.
What file format should you export data to for analysis and long-term storage?
Plain text, such as CSV.
In Excel, how do you limit what type of data can be entered into a column?
Data -> Data Validation
Allow limits the data typeData restricts the range of valuesIn Excel, how do you limit a column to a fixed list of choices?
Data -> Data Validation -> Allow -> List
Then type the values into Sources separated by commas, or select a range of cells.
This also gives you a dropdown for data entry.
In Excel, how do you stop dates (or data that looks like dates) from being reformatted?
Select the date column, then Home -> Number -> dropdown -> Text.
Dates then stay as entered and export correctly.