As part of the study described in Exercise 3.1, the experimenters obtained the same kind of data from a smaller group who had read the passage before answering the questions (called the Passage group). Their data follow.

a) What can you tell just by looking at these numbers? Do students do better when they have read the passage?

b) Plot these data by hand on one side of a stem-and-leaf display and the NoPassage data on the other side of the same stem-and-leaf display.

c) What can you see by looking at this stem-and-leaf display?

d) A further discussion of this example can be found at https://www.uvm.edu/~dhowell/fundamentals9/Chapters/Chapter3/Katzfolder/
katz.html although it also covers material that we will discuss later in this book.

Exercise 3.1

Have you ever wondered how you would do on the SATs if you didn’t even bother to read the passage you were asked about?5 Katz, Lautenschlager, Blackburn, and Harris (1990) asked students to answer SAT-type questions without seeing the passage on which the questions were based. This was called the NoPassage group. Data closely resembling what they obtained follow, where the dependent variable was the individual’s score on the test.

Transcribed Image Text:

66 75 72 71 55 56 72 93 73 72 72 73 91 66 71 56 59