Question

A researcher wishes to estimate, with 99% confidence, the population proportion of adults who are confident with their country's banking system. His estimate must be accurate within 3% of the population proportion. (a) No preliminary estimate is available. Find the minimum sample size needed. (b) Find the minimum sample size needed, using a prior study that found that 26% of the respondents said they are confident with their country's banking system. (c) Compare the results from parts (a) and (b).

Answer #1

c = 99%

z- score for 99% is 2.58

E = 3% (0.03)

n = (z/E)^2 * p(1 - p)

(a) p = 1 - p = 0.5

n = (2.58/0.03)^2 * (0.5 * 0.5) = 1844

(b) p = 0.26

n = (2.58/0.03)^2 * 0.26(1 - 0.26) = 1419

(c) With no estimate of the population proportion available, we make a conservative estimate of the sample size. This will always be greater than the sample size estimate made with a prior knowledge about the population proportion.

**[Are you satisfied with my answer? If not please let me
know. If yes, please give me a positive rating.
Thanks.]**

A researcher wishes to estimate, with 95% confidence, the
population proportion of adults who are confident with their
country's banking system. His estimate must be accurate within 4%
of the population proportion. (a) No preliminary estimate is
available. Find the minimum sample size needed. (b) Find the
minimum sample size needed, using a prior study that found that
28% of the respondents said they are confident with their
country's banking system. (c) Compare the results from parts (a)
and (b).

A researcher wishes to? estimate, with 95?% ?confidence, the
population proportion of adults who are confident with their?
country's banking system. His estimate must be accurate within 3?%
of the population proportion. ?(a) No preliminary estimate is
available. Find the minimum sample size needed. ?(b) Find the
minimum sample size? needed, using a prior study that found that
22?% of the respondents said they are confident with their?
country's banking system. ?(c) Compare the results from parts ?(a)
and ?(b)....

A researcher wishes to estimate, with 99% confidence, the
population proportion of adults who think the president of their
country can control the price of gasoline. Her estimate must be
accurate within 2% of the true proportion.
a) No preliminary estimate is available. Find the minimum
sample size needed.
b) Find the minimum sample size needed, using a prior study
that found that 38% of the respondents said they think their
president can control the price of gasoline.
c) Compare...

A researcher wishes to estimate, with 99% confidence, the
population proportion of adults who think the president of their
country can control the price of gasoline. Her estimate must be
accurate within 2% of the true proportion.
a) No preliminary estimate is available. Find the minimum
sample size needed.
b) Find the minimum sample size needed, using a prior study
that found that 32% of the respondents said they think their
president can control the price of gasoline.
c) Compare...

A researcher wishes to estimate, with
99%
confidence, the population proportion of adults who say
chocolate is their favorite ice cream flavor. Her estimate must be
accurate within
2%
of the population proportion.
(a) No preliminary estimate is available. Find the minimum
sample size needed.
(b) Find the minimum sample size needed, using a prior study
that found that
18%
of the respondents said their favorite flavor of ice cream is
chocolate.
(c) Compare the results from parts (a) and...

A researcher wishes to estimate, with 99 % confidence, the
population proportion of adults who think the president of their
country can control the price of gasoline. Her estimate must be
accurate within 4 % of the true proportion. a) No preliminary
estimate is available. Find the minimum sample size needed. b)
Find the minimum sample size needed, using a prior study that
found that 28 % of the respondents said they think their president
can control the price of...

A researcher wishes to estimate, with 90% confidence, the
population proportion of adults who think Congress is doing a good
or excellent job. Her estimate must be accurate within 22% of the
true proportion.
(a) No preliminary estimate is available. Find the minimum
sample size needed.
(b) Find the minimum sample size needed, using a prior study
that found that 26% of the respondents said they think Congress is
doing a good or excellent job.
(c) Compare the results from...

A researcher wishes to? estimate, with 90?% ?confidence, the
population proportion of adults who say chocolate is their favorite
ice cream flavor. Her estimate must be accurate within 5?% of the
population proportion. ?(a) No preliminary estimate is available.
Find the minimum sample size needed. ?(b) Find the minimum sample
size? needed, using a prior study that found that 36?% of the
respondents said their favorite flavor of ice cream is chocolate.
?(c) Compare the results from parts? (a) and?...

A researcher wishes to estimate, with 95%
confidence, the population proportion of adults who think the
president of their country can control the price of gasoline. Her
estimate must be accurate within 5% of the true proportion.
a) No preliminary estimate is available. Find the minimum
sample size needed.
b) Find the minimum sample size needed, using a prior study
that found that
22%
of the respondents said they think their president can control
the price of gasoline.
c) Compare...

A researcher wishes to estimate, with 90% confidence, the
population proportion of adults who think the president of their
country can control the price of gasoline. Her estimate must be
accurate within 4% of the true proportion. No preliminary estimate
is available. Find the minimum sample size needed. Find the minimum
sample size needed, using a prior study that found that 28% of the
respondents said they think their president can control the price
of gasoline. Compare the results. What...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 7 minutes ago

asked 20 minutes ago

asked 21 minutes ago

asked 29 minutes ago

asked 43 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago