1. Telling Visual Stories from Data
Graphs
Telling Visual Stories
from Data

2. Simple Linear Graph Parts
X axis (independent variable): scale, units, title
Y axis (dependent variable): scale, units, title
Title
1-2 sentence Description
Title
Making simple graphs is very straightforward. The X axis is always the independent variable, the factor that you control like the time or the temperature or the amount. The Y axis is always the dependent variable, the factor that you measure or count. The title is a precise description of the graph
Dependent Variable
Independent Variable

3. Stories and Questions
What can you say about this graph? What is its shape? What trend does it suggest? How would you describe the graph mathematically? What does the graph tell you about tweets? What questions does the graph raise?

4. Twitter Activity
How would you analyze this graph? What are its maxs and mins and what might this “inflection points” suggest? Write a brief description of the activity the graph suggests.
(Seattle developer Damon Cortesi has written a great little perl script that will generate your Twitter Stats which you can be make into some cool graphs of using the Numbers app. Here are my current Twitter Stats.

5. Graphs Can Simplify Complex Stories
This graph shows how patterns in data can be made visual. In this case one can see that the pulse is quite elevated at the end of a 10 min run and that the pulse gradually decreases thereafter but not in a linear fashion. In fact the pulse rate drops but then shoots back up, but not quite as high. We now know that the heart rate as indicated by the pulse rate is part of a negative feedback loop. When the pulse drops too low, the heart is stimulated to beat faster to supply needed oxygen. As the oxygen demand decreases, the pulse reduces but overshoots and the heart is stimulated once again. If we were only looking at the data in table form, we probably wouldn’t see this feedback pattern.

6. What is the story?

7. What is the story?

8. Test Scores and Socioeconomic Status
What does this graph suggest? What questions does it raise?

9. One last story