1. [6 points] In discussing significance testing, Healey, Prus and Lieflander (page 330-336) differentiate between one-tailed and two-tailed tests. What makes a test one-tailed or two-tailed?

2. [6 point] Healey, Prus and Lieflander discuss (alpha) or Type I error (page 210). What is a Type I or error, and how often do we make this error?

3. [8 points] Healey, Prus and Lieflander discuss (beta) or Type II error (pages 211). What is a Type II or error, and how often do we make this error?