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Data and Society 9-12 / Week 01 / Wednesday
3/6
Week 01 · What Is Data?

Wednesday

Count Lab: Observe first
// From raw facts to information the Commons can act on
⏱ about 20 min

Wednesday: Count Lab: Observe First

Wren sets a stack of books from the reading corner on a workbench. "Before we ask any person anything, let's practice on something that cannot mind being counted."

Comet laughs. "Books never complain."

"We pick one variable," Wren says, "then we watch and record. No guessing, no asking."

Comet grabs the top book. "I bet most of these are story books."

Nova hovers over the stack and draws a grid of light on the bench. "Would you like a hint?" she asks. "Write your guess down first. Then let the tally decide."

Wren hands you a pencil. "Your turn, data analyst. Pick a shelf at home."

Your mission

Direct observation is one way to find out what is going on. You watch and record what is there instead of asking questions.

Today you observe one shelf of books or one sock drawer at home. You choose one variable, tally it and build a table.

Tables, diagrams, text and other visuals can share what data show. Your table will share what your shelf shows.

  • One shelf of books, or one drawer of socks, at home
  • Paper and a pencil
  • A ruler for neat columns (optional)
  1. Choose one shelf or one drawer. If it belongs to someone else, ask them first.
  2. Choose one variable to observe, such as the type of book, the cover color or the sock color.
  3. Write three or four groups for that variable, plus a group called Other.
  4. Predict which group will be biggest. Write your prediction at the top of your paper.
  5. Look at one item at a time and make one tally mark next to its group.
  6. Count the tally marks in each group and write each total in a table.
  7. Add the totals. Then count the items again and check that the two numbers match.
  8. Write one question your tally could answer.

Wren's example

Wren tallied one shelf in the Commons reading corner by type of book. This is made-up data from the Commons Count story.

Type of bookCount
How-to9
Story8
Reference4
Poetry3
CHECK WREN'S TALLY
  • Read the question.
  • Tap your answer.
Comet predicted most books would be story books. Which group is actually biggest?
How many books are on Wren's shelf in total?
How many more how-to books are there than poetry books?
Which question could Wren's tally answer?
What the lab showsTrue or false?
Direct observation means watching and recording instead of asking.?
Writing your prediction first makes it easy to check later.?
If your totals add up to the number of items, a tally mark is probably not missing.?
A tally of book types can tell you which book people like best.?
WHY THIS EXERCISEData can only answer questions about the variable you actually recorded.
On paper, draw your tally table neatly. Give it a title that names the shelf or drawer and the variable you chose.

Excellent observing. Tomorrow the crew uses data to look at a real decision for the Commons.

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