If a nominal independent variable has 4 possible categories, the number of dummy variables needed to uniquely represent these categories is:
a. 5.
b. 4.
c. 3.
d. 2.
Q. 2The p-value of a test is the probability of observing a test statistic at least as extreme as the one computed given that the null hypothesis is true.
Indicate whether the statement is true or false
Q. 3In explaining the income earned by college graduates, which of the following independent variables is best represented by a dummy variable?
a. Grade point average
b. Age
c. Number of years since graduating from high school
d. College major
Q. 4Think about a situation where you have a test for a virus. First, you are tested positive or negative. Second, you either really do have the virus or you don't.
a. If you actually have the virus but the test did not catch it, which error has been made and what is the impact of that error?
b. If you actually don't have the virus but the test says you did, which error is being made and what is the impact of this error?
c. Which error is the worst one to commit in this situation and why?
Q. 5In explaining starting salaries for graduates of psychology programs, which of the following independent variables would not best be represented with dummy variables?
a. Marital status
b. Grade point average
c. Race
d. Gender
Q. 6Explain why a Type I error and a Type II error have an inverse relationship.
Q. 7In explaining students' test scores, which of the following independent variables would not best be represented with indicator variables?
a. Gender
b. Race
c. Number of hours studying for the test
d. Marital status