A) Find the z critical value for a 90% confidence level:
Zc=
B) Find the z critical value for an 84% confidence level:
Zc=
C) The higher the confidence, the narrower the confidence
interval
True or False
D) The greater the sample size, the mnarrower the confidence
interval
True or False
E) In a recent study of 84 eighth graders, the mean number of
hours per week that they watched TV was 22.3. Assume population
standard deviation is 5.8 hours....
Find the critical value
t/α2
needed to construct a confidence interval of the given level
with the given sample size. Round the answers to three decimal
places.
(a) For level
99%
and sample size
9
(b) For level
99.5%
and sample size
14
(c) For level
80%
and sample size
29
(d) For level
90%
and sample size
11
Confidence interval when sigma is unknown.
2. Find the critical value
tα2
for the given level and sample size:
Level 90%, Sample size is 13,
df =
, so the
critical value is: =
Level 98%, Sample size is 10
df =
, so the
critical value is: =
Level 80%, Sample size is 17
df =
, so the
critical value is: =
Level 99%, Sample size is 77
df =
,...
Find the critical z value for a confidence level of
94%.
Critical Value= round answer to 2 decimal places)
Out of 300 people sampled, 246 had kids. Based on this,
construct a 99% confidence interval for the true population
proportion of people with kids.
Give your answers as decimals, to three places
I am 99% confident that the proportion of people who have kids is
between and
Out of 300 people sampled, 255 had kids. Based on this,
construct a 95%...
Find the level of a two-sided confidence interval that is based
on the given value of t and the given sample size.
6. t = 1.943, sample size n = 7. (Multiple choice)
Choices: 80%, 90%, 95%, 98%
7. t = 2.093, sample size n = 20.
Choices: 90%, 98%, 95%, 99%
10. t = 1.753, n = 16
Choices: 80%, 90%, 95%, 99%
For a confidence level of 98%, find the critical value for a
normally distributed variable. The sample mean is normally
distributed if the population standard deviation is known.
Find the critical value Χ2/L corresponding to a sample size of 9
and a confidence interval of 99%. (Draw the graph)
Please write neatly, and show work, no calculator.