Question
In: Statistics and Probability
A publisher wants to estimate the mean length of time (in minutes) all adults spend reading...
A publisher wants to estimate the mean length of time (in minutes) all adults spend reading newspapers. To determine this estimate, the publisher takes a random sample of 15 people and obtains the results below. From past studies, the publisher assumes σ is 2.1 minutes and that the population of times is normally distributed.
10 12 7 10 11 8 12 8 11 7 6 11 8 8 12
a) The 90% confidence interval is ____
b) The 99% confidence interval is ____
c) Which interval is wider?
-
The 99% confidence interval
-
The 90% confidence interval
Solutions
orchestra answered 1 year agoRelated Solutions
A publisher wants to estimate the mean length of time (in minutes) all adults spend reading...
A publisher wants to estimate the mean length of time (in
minutes) all adults spend reading newspapers. To determine this
estimate, the publisher takes a random sample of 15 people and
obtains the results below. From past studies, the publisher
assumes sigma is 1.5 minutes and that the population of times is
normally distributed. 10 9 10 6 10 8 9 8 12 11 11 10 12 9 12
Construct the 90% and 99% confidence intervals for the population
mean....
A research council wants to estimate the mean length of time (in minutes) that the average...
A research council wants to estimate the mean length of time (in
minutes) that the average U.S. adult spends watching television
using digital video recorders (DVR’s) each day. To determine the
estimate, the research council takes random samples of 35 U.S.
adults and obtains the following times in minutes.
24
27
26
29
33
21
18
24
23
34
17
15
19
23
25
29
36
19
18
22
16
45
32
12
24
35
14
40
30
19
14...
A research council wants to estimate the mean length of time (in minutes) that the average...
A research council wants to estimate the mean length of time (in
minutes) that the average U.S. adult spends watching television
using digital video recorders (DVR’s) each day. To determine the
estimate, the research council takes random samples of 35 U.S.
adults and obtains the following times in minutes.
24
27
26
29
33
21
18
24
23
34
17
15
19
23
25
29
36
19
18
22
16
45
32
12
24
35
14
40
30
19
14...
An advertising executive wants to estimate the mean amount of time that consumers spend with digital...
An advertising executive wants to estimate the mean amount of
time that consumers spend with digital media daily. From past
studies, the standard deviation is estimated as 42 minutes.
A. What sample size is needed if the executive wants to be 90%
confident of being correct to within plus or minus 4 minutes?
B. If 99% confidence is desired, how many consumers need to be
selected?
An advertising executive wants to estimate the mean weekly amount of time consumers spend watching traditional...
An advertising executive wants to estimate the mean weekly
amount of time consumers spend watching traditional television
daily. Based on previous studies, the standard deviation is
assumed to be 20 minutes. The executive wants to estimate, with
99% confidence, the mean weekly amount of time to within ±5
minutes.
a. What sample size is needed?
b. If 95% confidence is desired, how many
consumers need to be selected?
An advertising executive wants to estimate the mean weekly amount of time consumers spend watching traditional...
An advertising executive wants to estimate the mean weekly
amount of time consumers spend watching traditional television
daily. Based on previous studies, the standard deviation is
assumed to be 21 minutes. The executive wants to estimate, with
99% confidence, the mean weekly amount of time to within ± 6
minutes.
a. What sample size is needed?
b. If 95% confidence is desired, how many consumers need to
be selected?
An advertising executive wants to estimate the mean weekly amount of time 18- to 24-year-olds spend...
An advertising executive wants to estimate the mean weekly
amount of time 18- to 24-year-olds spend watching traditional
television in a large city. Based on studies in other cities, the
standard deviation is assumed to be 10 minutes. The executive wants
to estimate, within 99% confidence, the mean weekly amount of time
within ±3 minutes.
a. What sample size is needed?
b. If 95% confidence is desired, how many 18- to 24-year-olds
need to be selected?
c. If she wants...
A group of researchers estimates the mean length of time (in minutes) the average U.S. adult...
A group of researchers estimates the mean length of time (in
minutes) the average U.S. adult spends watching television using
digital recorders and other forms of time-shifted television each
day. To do so, the group takes a random sample of 40 U.S. adults
and obtains the times (in minutes) listed below. Assume the
population standard deviation to be 6.5 minutes. construct a 90%
and 99% confidence interval for the population mean.
29, 27, 28, 26, 14,28,32, 12, 16, 21, 17,...
Suppose that Apple Inc. wished to estimate the mean time people spend on their phones every...
Suppose that Apple Inc. wished to estimate the mean time people
spend on their phones every day. In a random sample of 30 phones
users the mean time was found to be 150 minutes with a standard
deviation of 70 minutes.
* Construct a 90% confidence interval for the mean time people
spend on their phone every day.
* Construct a 95% confidence interval for the mean time people
spend on their phone every day.
* Construct a 99% confidence...
Statistic Q3(a) To estimate the mean amount of time children spend in physical activities daily, a...
Statistic
Q3(a) To estimate the mean amount of time children spend in
physical activities daily, a researcher randomly selects 8 children
and records the number of hours they spend in physical activities
in one day. The numbers of hours are: 4.1, 1.2, 4.6, 2.4, 3.2, 1.8,
2.4, and 0.7. Obtain a 95% confidence interval of the mean number
of hours that children spend in physical activities.
Q3(b) It is found that the average lifespan of 100 smart phones
is 23.5...
ADVERTISEMENT
ADVERTISEMENT
Latest Questions
- 1. Explain the following behaviour by two employees and whether it is appropriate. Sam comes from...
- Complete a final business plan that should include all sections of a business plan including any...
- Badlands, Inc. manufactures a household fan that sells for $20 per unit. All sales are on...
- An array A of n distinct numbers are said to be unimodal if there exists an...
- We often use grinding in closed circuit, and have a targeted value for a circulated load....
- Ocean park SWOT on leadership style - Strength - Weakness - Opportunities - Threats
- C LANGUAGE ONLY Write a C program to count the total number of duplicate elements in...
ADVERTISEMENT