Study guide: Use Spreadsheet Cells as a Data Model
On a paper sheet put B2=6,C2=4 and B3=8,C3=5. Use =B2+C2, copy the relative formula down one row, and choose a display for exact lookup versus category comparison.
Ideas to explain in your own words
- A spreadsheet cell address combines a column label and a row number. Values at nearby addresses can have different meanings. In this paper sheet A contains item labels and B contains counts; row 1 is the heading and rows 2–4 are data. Cell addresses refer to locations rather than quantities.
- A formula uses values from named cells. The expression equals B2 plus B3 adds those cell values, not their row numbers or addresses. A formula’s result changes when a referenced value changes. Our paper sheet gives all values; no spreadsheet app is required.
- A relative spreadsheet reference changes with the formula’s copied position. Moving a formula down one row changes its relative row references by one. This lesson states that all references are relative; dollar-sign fixed references are outside this model. Copying a formula is different from copying its old displayed number.
- A chart represents data using visual rules. A bar chart can compare category counts; a line chart can show values over ordered time. A table supplies precise values and a text description can explain patterns. The right display depends on the question, not on decoration.
Useful vocabulary
- cell address
- A column-and-row location in a spreadsheet.
- relative reference
- A reference that shifts when a formula is copied.
- chart
- A visual representation of data.
Watch your reasoning
- Do not treat the header row as a data count.
- Do not add the row numbers 2 and 3 in place of the cell contents.
- Do not keep the old referenced row when the model says the reference is relative.
- Do not join unrelated category counts as though they form a time sequence.
A worked review example
Value at B2. Sheet: A2=tiles, B2=6; A3=pencils, B3=4; A4=cards, B4=8. What is requested? The supported answer is 6. Find the specified column and row before interpreting its value. Do not treat the header row as a data count. A spreadsheet cell address combines a column label and a row number. The supplied facts, rather than an assumed real-world detail, determine this paper case. Compare the recorded action or value with the stated rule before choosing an answer. Compare counts of three toy categories. Which representation best fits the stated purpose? The supported answer is Labeled bar chart. Match the data type and question to the stated chart purpose, retaining labels and units. Do not join unrelated category counts as though they form a time sequence. The supplied facts, rather than an assumed real-world detail, determine this paper case. Compare the recorded action or value with the stated rule before choosing an answer.
Make a practice plan
- Draw or tell one computing idea from each of the four lessons. Give one example of using each idea.
- Use the example to explain one mistake to avoid.
- Try the unit review before opening the explanations.
- Try the new task on paper or say your answer. Then compare your steps with the example answer.