# stats pt 1

Shargrodosky, Curhan, Curhan, and Eavey(2010)studied whether hearing loss among teens has increased. The researchers compared a random sample of 2928 teens from a 1994 study to a random sample of 1771 teens from a 2006 study . In the 1994 study, 480 teens had hearing loss while in the 2006 study, 333 had hearing loss. The researchers are trying to estimate the difference in the two populations,

${}_{}$

π

2006

π

1994

. The researchers tested the hypotheses

${}_{}$

H

0

:

π

2006

π

1994

=

0

vs

H

A

:

π

2006

π

1994

0

They calculated a p-value=0.0343 and Z=2.12 and designated

=

0.05

. Answer the following questions using this information.

Identify the explanatory and the response variable.

Flag this QuestionQuestion 210 pts

Select all of the following statements that are correct.

${}_{}$

H

0

.

${}_{}$

H

0

.

Flag this Question

A clinical study conducted in the early 1990s recruited 324 pregnant women who were HIV-positive. The researchers believe that the pregnant women taking AZT will have fewer babies born HIV-positive. Of the 164 women who were randomly assigned to use the experimental (at the time) drug AZT, 13 had HIV-positive babies. Of the 160 women who were randomly assigned to receive a placebo, 40 had HIV-positive babies. The data has been summarized in the following table. Use this information to answer the following questions.

 AZT mothers Placebo mothers ROW TOTAL HIV-positive baby 13 40 53 not HIV-positive baby 151 120 271 COLUMN TOTAL 164 160 n = 321

Flag this QuestionQuestion 38 pts

Is this study an observational study or an experiment?

Flag this QuestionQuestion 46 pts

Identify all of the parameters for this study.

${}_{}$

π

A

Z

T

is the long-run proportion of HIV-positive babies born to women taking AZT.

${}_{}$

π

P

l

a

c

e

b

o

is the long-run proportion of HIV-positive babies born to women taking the placebo.

${}_{}$

π

H

I

V

is the long-run proportion of HIV-positive babies born .

${}_{}$

π

n

o

n

is the long-run proportion of non-HIV-positive babies born.

${}_{}$

π

A

Z

T

is the long-run proportion of women taking AZT.

${}_{}$

π

P

l

a

c

e

b

o

is the long-run proportion of women taking the placebo.

Flag this QuestionQuestion 56 pts

Write out the null and alternative hypotheses for this study.

${}_{}$

H

0

:

π

P

l

a

c

e

b

o

π

A

Z

T

=

0

vs

H

A

:

π

P

l

a

c

e

b

o

π

A

Z

T

0

${}_{}$

H

0

:

π

P

l

a

c

e

b

o

π

A

Z

T

=

0

vs

H

A

:

π

P

l

a

c

e

b

o

π

A

Z

T

<

0

${}_{}$

H

0

:

π

P

l

a

c

e

b

o

π

A

Z

T

=

0

vs

H

A

:

π

P

l

a

c

e

b

o

π

A

Z

T

>

0

Flag this QuestionQuestion 66 pts

Are the validity conditions satisfied for this study?

Flag this Question

A random selection of married couples from Joliet, IL were asked to state how much TV they watched in the week of June 2 to June 8, 2019. The researchers are trying to determine if there is any difference in the TV watching habits between married couples. A matched pairs design was used and for each couple the difference (Wife – Husband) was calculated for each couple. The sample summary statistics and boxplots of the data are presented below.

Flag this QuestionQuestion 76 pts

State the null and alternative hypotheses.

${}_{}$

H

0

:

μ

d

=

0

vs

H

A

:

μ

d

>

0

${}_{}$

H

0

:

μ

w

i

v

e

s

μ

h

u

s

b

a

n

d

s

=

0

vs

H

A

:

μ

w

i

v

e

s

μ

h

u

s

b

a

n

d

s

0

${}_{}$

H

0

:

μ

w

i

v

e

s

μ

h

u

s

b

a

n

d

s

=

0

vs

H

A

:

μ

w

i

v

e

s

μ

h

u

s

b

a

n

d

s

>

0

${}_{}$

H

0

:

μ

d

=

0

vs

H

A

:

μ

d

0

Thanks for installing the Bottom of every post plugin by Corey Salzano. Contact me if you need custom WordPress plugins or website design.