Question

True or false?:

13) For a sample mean, the 99% confidence interval is wider than the 95% confidence interval. 14) The larger the sample size the more likely x̅ is close to μ.

15) Changing sample size has no effect on power when using the t test.

16) For the independent two-sample t test, increasing sample variances decreases power.

Answer #1

Ans:

13)**True**,Larger the confidence level,wider the
confidence interval.

14)**False**,as larger the sample size,larger the
test statistic,smaller the p-value,more likely to reject the null
hypothesis.

15)**False**,larger the sample size,larger the
power,as we will be more likely to reject the null hypothesis.

16)**True**,Increasing the sample
variance,increases the standard error,hence decreases the test
statistic value,less likely to reject the null hypothesis,larger
the probability of type II error and lower the power

Which of the following statements is true?
The 95% confidence interval is wider than the 99% confidence
interval.
The ONLY way to reduce the width of a confidence interval is to
reduce the confidence level.
The required sample size for a population mean is ONLY
dependent on population variance.
Given population variance and sampling error, higher confidence
level results in larger sample size.

Given a sample size 18 with a 99% confidence interval for the
mean μ, and a known standard deviation (26.64, 33.25), calculate
the 95% confidence interval for μ.

Sample mean is always:
The lower endpoint of the 99% confidence interval.
The middle of the confidence 99% interval.
The upper endpoint of the 99% confidence interval.
The average monthly electricity consumption in a random sample
of 100 households in February 2016 in North Kingstown was 637
kilowatt hours (kWh) with sample standard deviation s=45kwh. A 95%
confidence interval for the true electricity consumption in North
Kingstown is
637 ± 1.95 * 45/10
637 ± 1.96 * 45
637 ±...

Which of the following is TRUE?
A.
The confidence interval is narrower if the sample size is
smaller.
B.
The confidence interval is narrower if the level of significance
is smaller.
C.
The confidence interval is wider if the level of confidence
level is larger.
D.
The confidence interval is wider if the sample size is
larger.

True or false? A larger sample size produces a longer confidence
interval for μ.
False. As the sample size increases, the maximal error
decreases, resulting in a shorter confidence interval.True. As the
sample size increases, the maximal error decreases, resulting in a
longer confidence interval. True. As the
sample size increases, the maximal error increases, resulting in a
longer confidence interval.False. As the sample size increases, the
maximal error increases, resulting in a shorter confidence
interval.
True or false? If the...

The width of a confidence interval will be:
Narrower for 98 percent confidence than for 90 percent
confidence.
Wider for a sample size of 64 than for a sample size of 36.
Wider for a 99 percent confidence than for 95 percent
confidence.
Narrower for a sample size of 25 than for a sample size of
36.
None of these.

True or false:
1. When constructing a confidence interval for a sample
Mean, the t distribution is appropriate whenever the sample size is
small.
2. The sampling distribution of X (X-bar) is not always
a normal distribution.
3. The reason sample variance has a divisor of n-1
rather than n is that it makes the sample standard deviation an
unbiased estimate of the population standard
deviation.
4. The error term is the difference between the actual
value of the dependent...

(a)
Construct a 95% confidence interval about
Mu μ if the sample size, n, is 34
Lower bound:
___________
; Upper bound:
______________
(Use ascending order. Round to two decimal places as
needed.)
(b) Construct a 95% confidence interval about mu μ if
the sample size, n, is 51.
Lower bound:
____________
; Upper bound:
____________
(Use ascending order. Round to two decimal places as
needed.)
How does increasing the sample size affect the margin
of error, E?
A.
The...

Calculate the 95% confidence interval for μ given the random
sample below:
16
13
14
14
Fill in the blanks for the CI: Estimate ± Critical Value ×
Standard Error
x¯± t* ×s/n
["57.00", "19.00", "14.25"] ± ["1.96",
"3.182", "2.776"] ×
["1.26", "1.88", "1.09"]
/SQRT( ["4", "3", "5"]
)
95%CI for μ ( ["12.2, 16.3", "10.2, 18.3", "17.8, 20.2"]
)

Use the t-distribution to find a confidence interval
for a mean μ given the relevant sample results. Give the best point
estimate for μ, the margin of error, and the confidence interval.
Assume the results come from a random sample from a population that
is approximately normally distributed.
A 95% confidence interval for μ using the sample results
x̅=10.4, s=5.3, and n=30.
Round your answer for the point estimate to one decimal place,
and your answers for the margin of...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 17 minutes ago

asked 24 minutes ago

asked 26 minutes ago

asked 26 minutes ago

asked 29 minutes ago

asked 49 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago