Question Help

According to areport, the standard deviationof monthly cell phone bills was $49.73 three years ago. A researcher suspects that the standard deviationof monthly cell phone bills is less today.

(a)

Determine the null and alternative hypotheses.

(b)

Explain what it would mean to make a Type I error.

(c)

Explain what it would mean to make a Type II error.

(a) State the hypotheses.

H0:

mu

p

p

sigma

greater than

>

not equals

equals

=

less than

<

$

nothing

H1:

mu

sigma

p

p

not equals

equals

=

greater than

>

less than

<

$

nothing

(Type integers or decimals. Do notround.)

(b) Explain what it would mean to make a Type I error. Choose the correct answer below.

A.

The sample evidence led the researcher to believe the standard deviationof the monthly cell phone bill is differentfrom $49.73, when in fact the standard deviationof the bill is $49.73.

B.

The sample evidence did not lead the researcher to believe the standard deviationof the monthly cell phone bill is lessthan $49.73, when in fact the standard deviationof the bill is lessthan $49.73.

C.

The sample evidence led the researcher to believe the standard deviationof the monthly cell phone bill is lessthan $49.73, when in fact the standard deviationof the bill is $49.73.

D.

The sample evidence did not lead the researcher to believe the standard deviationof the monthly cell phone bill is differentfrom $49.73, when in fact the standard deviationof the bill is differentfrom $49.73.

(c) Explain what it would mean to make a Type II error. Choose the correct answer below.

A.

The sample evidence did not lead the researcher to believe the standard deviationof the monthly cell phone bill is lessthan $49.73, when in fact the standard deviationof the bill is lessthan $49.73.

B.

The sample evidence did not lead the researcher to believe the standard deviationof the monthly cell phone bill is differentfrom $49.73, when in fact the standard deviationof the bill is differentfrom $49.73.

C.

The sample evidence led the researcher to believe the standard deviationof the monthly cell phone bill is lessthan $49.73, when in fact the standard deviationof the bill is $49.73.

D.

The sample evidence led the researcher to believe the standard deviationof the monthly cell phone bill is lessthan $49.73, when in fact the standard deviationof the bill is lessthan $49.73.

Click to select your answer(s).