Math 143 C/E, Spring 2001
IPS Reading Questions
Chapter 6, Section 3

1. What are the concerns that go into the deciding of a pre-arranged significance level a that serves as the dividing line between rejecting and not rejecting the null hypothesis?

   
   
   
   
   
   
   
   
   
   
   
   
   
   
   

2. What do the authors mean by the phrase “statistical significance is not the same as practical significance”?

   
   
   
   
   
   
   
   
   
   
   
   
   
   
   

3. The paragraph that begins with “Tests of significance ...” on p. 479 is very revealing, both as to the context of the inference procedures we have learned, and as to how much of the iceberg that is statistical inference still lies below the surface (never to be studied in this course). Try to summarize and/or expound on this paragraph.

   
   
   
   
   
   
   
   
   
   
   
   
   
   
   

4. We have discussed how to interpret a confidence interval - that a level C confidence interval has probability C of containing the population parameter in question. How should one interpret the P value that one computes in a significance test?

   
   
   
   
   
   
   
   

5. Given this interpretation of a test of significance, why would it not be surprising that if you took a sample and, on each unit, measured 107 variables, possibly one or more of them would have an average that was significant at the 1% level when compared to the corresponding general population mean? Should this make you doubt the value of the population mean in this case?