Question

A sports analyst wants to estimate the true proportion of baseball players in the National League with a batting average of 0.400 or greater. They want to be 98% confident with a margin of error of 5%. How many players should be sampled if:

- No prior estimate of
*p*is available? - A previous study estimated that the proportion was 24%?

Answer #1

solution:

the given information as follows:

margin of error **E** = 5% =
**0.05**

confidence level = 98% = 0.98

so significance level = = 1-0.98 = 0.02

**critical value of z =
**

**a) if prior estimate p is not available**

we assume **
= 0.5** is prior estimate is not available to find the
requisite sample size.

so formula for margin of error is

so required sample size = 543 players, if prior estimate of p is not available

**b)**

**if prior estimate of p is 24%**

so **
= 0.24**

**since we cant take sample in fraction so the required
sample size would be 397 players.**

Your friend tells you that the proportion of active Major League
Baseball players who have a batting average greater than .300 is
different from 0.64, a claim you would like to test. The hypotheses
for this test are Null Hypothesis: p = 0.64, Alternative
Hypothesis: p ≠ 0.64. If you randomly sample 30 players and
determine that 24 of them have a batting average higher than .300,
what is the test statistic and p-value?

Your friend tells you that the proportion of active Major League
Baseball players who have a batting average greater than .300 is
different from 0.71, a claim you would like to test. The hypotheses
for this test are Null Hypothesis: p = 0.71, Alternative
Hypothesis: p ≠ 0.71. If you randomly sample 23 players and
determine that 14 of them have a batting average higher than .300,
what is the test statistic and p-value?

In 2004, professional baseball players in the National League
had a mean batting average of 0.260 for the year with a standard
deviation of 0.040.
(a) What percentage of batters had an average above 0.300?
(b) What percentage of batters had an average between 0.100 and
0.200?
(c) What percentage of batters had an average between 0.200 and
0.300? Use the normal error curve table to do your calculations
Explain briefly plz!!!!

Your friend tells you that the proportion of active Major League
Baseball players who have a batting average greater than .300 is
different from 0.77, a claim you would like to test. The hypotheses
for this test are Null Hypothesis: p = 0.77, Alternative
Hypothesis: p ≠ 0.77. If you randomly sample 24 players and
determine that 19 of them have a batting average higher than .300,
what is the test statistic and p-value?
Question 9 options:
1)
Test Statistic:...

Your friend tells you that the proportion of active Major League
Baseball players who have a batting average greater than .300 is
different from 0.74, a claim you would like to test. The hypotheses
here are Null Hypothesis: p = 0.74, Alternative Hypothesis: p ≠
0.74. If you take a random sample of players and calculate p-value
for your hypothesis test of 0.9623, what is the appropriate
conclusion? Conclude at the 5% level of significance.
Question 15 options:
1)
We...

Based on past data, the proportion of Major League Baseball
(MLB) players who bat left handed was 0.481. You are interested to
see if this is still the case. You conduct a sample of 23 players
and find that 10 are left handed hitters. The 95% confidence
interval is ( 0.2322 , 0.6374 ). What is the best conclusion of
those listed below?
Question 6 options:
1)
The confidence interval does not provide enough information to
form a conclusion.
2)...

18. A researcher wishes to be 95% confident that her estimate of
the true proportion of individuals who travel overseas is within 3%
of the true proportion.
a) Find the sample necessary if, in a prior study, a sample of
200 people showed that 40 traveled overseas last year. b)
b) If no estimate of the sample proportion is available, how
large should the sample be?

"Call me: A sociologist wants to construct a 95% confidence
interval for the proportion of children aged 8–12 living in NewYork
who own a cell phone.a. A survey by the National Consumers League
estimated the nationwide proportion to be 0.56. Using this
estimate, what sample size is needed so that the confidence
interval will have a margin of error of 0.02?b. Estimate the sample
size needed if no estimate of p is31. Changing jobs: A sociologist
sampled 200 people who...

.1) How large a sample must one take to be 90% confident that
the estimate is within 5% of the true
proportion of women over 55 who
are widows? A recent study indicated that 29% of the 100
women
over 55 in the study were
widows.
8. As a manufacturer of golf equipment, the Spalding
Corporation wants to estimate the proportion of
golfers who are
left-handed. (The company can use this information in
planning for the number of
right-handed and left-handed sets
of...

A mobile phone marketing company wants to survey a sample to
estimate the true proportion of all cell phone users that play
games on their phone. There is an old survey which showed that 61%
of the cell phone users played games on the phone. What is the
minimum number of cell phone users needed in the new survey to be
95% confident and with a margin of error 0f .02

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 34 minutes ago

asked 40 minutes ago

asked 40 minutes ago

asked 45 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 2 hours ago

asked 2 hours ago

asked 3 hours ago

asked 3 hours ago