Chapter 8, Problem 8.16P

A researcher is studying the effects of the college experience on attitudes, values, and behaviors and is comparing random samples of freshmen and seniors at the same university. Which of the following differences are significant?

a. Proportion calling parents at least once a day:

Freshmen	Seniors
$P_{s1}=0.24$	$P_{s2}=0.08$
$N_1=153$	$N_2=117$

b. Proportion with a “close friend” from another racial or ethnic group:

Freshmen	Seniors
$P_{s1}=0.15$	$P_{s2}=0.26$
$N_1=155$	$N_2=114$

c. Proportion saying that they are “very interested” in national politics:

Freshmen	Seniors
$P_{s1}=0.46$	$P_{s2}=0.48$
$N_1=147$	$N_2=111$

d. Average score on a scale that measures political ideology. On a scale, 10 means “very conservative” and 1 means “very liberal”.

Freshmen	Seniors
${\bar{X}}_1=5.23$	${\bar{X}}_2=5.12$
$s_1=1.78$	$s_2=1.07$
$N_1=145$	$N_2=105$

e. Average score on a scale that measures support for traditional gender roles. This scale ranges from 7 (“Very traditional”) to 1 (“Very non-traditional”)

Freshmen	Seniors
${\bar{X}}_1=2.07$	${\bar{X}}_2=2.17$
$s_1=1.23$	$s_2=0.78$
$N_1=143$	$N_2=111$