Read the first part of Tufte's booklet (pages 5-15) and answer the questions below.

Part I: Dr. Snow and the Cholera Epidemic

1. Look at Tufte's description of Dr. Snow's displays of data(pages 5-15). What is the story? Why was this an important case study of visual displays of data? What were the elements of this story that pulled the ideas and data together into new knowledge?

2. Considering the map graph, spanning pages 8-9:

a. What data is it displaying?

b. Which of the displayed data is (are) the cause(s)? Which is (are) are the effect(s)?

c. How do you know?

d. Why is it an improvement to the time graph on page 7?

e. How does it compare with the other bar graphs of the data? What information is unique to each?

f. Why do you think Tufte purposefully left it black and white except for sight additions of the yellow?

g. What are the "outliers" in this graph? That is, items that don't seem to fit with the rest of the story?

h. What are the limitations of such a "dot map?" (See definition of dot map on page 13.)

Read the remainder of Tufte's booklet and answer the questions below.

Part II: The ChallengerExample

1. What went wrong in the space shuttle case - why did the Challenger explode? What did the presentation of data have to do with the explosion?

2. How did the process of decision making differ between the Challenger scientists and Dr. Snow? In particular, what steps did Dr. Snow take that the space shuttle engineers and administrators miss?

3. Looking at the slides the Thiokol engineers created BEFORE the launch. What are 5 specific things that made these slides a poor display of the data? How does Tufte correct for this in his displays of the data on pages 22-23?

4. Are Tufte's displays more effective? Do you think he could have changed NASA administrators' minds with this display?