Question

A study of identity theft looked at how well consumers protect themselves from this increasingly prevalent crime. The behaviors of 64 college students were compared with the behaviors of 57 nonstudents. One of the questions was "When asked to create a password, I have used either my mother's maiden name, or my pet's name, or my birth date, or the last four digits of my social security number, or a series of consecutive numbers." For the students, 25 agreed with this statement while 29 of the nonstudents agreed.

(a) Display the data in a two-way table.

Students Nonstudents Total

Agreed

Disagreed

Total 121

Perform the chi-square test. (Round your χ2 to three decimal places and round your P-value to four decimal places.)

χ2 =

df =

P-value =

Summarize the results.

We can conclude at the 5% level that students and nonstudents differ in the response to this question.

We cannot conclude at the 5% level that students and nonstudents differ in the response to this question.

(b) Reanalyze the data using the methods for comparing two proportions that we studied in the previous chapter. Compare the results and verify that the chi-square statistic is the square of the z statistic. (Test students who agreed minus nonstudents who agreed. Round your z to two decimal places and round your P-value to four decimal places.)

z =

P-value =

(c) The students in this study were junior and senior college students from two sections of a course in Internet marketing at a large northeastern university. The nonstudents were a group of individuals who were recruited to attend commercial focus groups on the West Coast conducted by a lifestyle marketing organization. Discuss how the method of selecting the subjects in this study relates to the conclusions that can be drawn from it.

Answer 1

(C)

The students were selected were doing course in Internet marketing at a large northeastern university. The nonstudents were a group of individuals who were recruited to attend commercial focus groups on the West Coast conducted by a lifestyle marketing organization. So, both groups are educated enough to know the pros and cons of identity theft. So, proportion of students and nonstudents who agree/disagree with the statements may be approximately identical.