In: Math
A scientist has read that the mean birth weight μ of babies born
at full term...
A scientist has read that the mean birth weight μ of babies born
at full term is 7.3 pounds. The scientist, believing that the mean
birth weight of babies born at full term is less than this value,
plans to perform a statistical test. She selects a random sample of
50 birth weights of babies born at full term. Suppose that the
population of birth weights of babies born at full term has a
standard deviation of 1.7 pounds and that the scientist performs
her hypothesis test using the 0.01 level of significance.
Based on this information, answer the questions below. Carry
your intermediate computations to at least four decimal places, and
round your responses as indicated.
(If necessary, consult a list of formulas.)
What are the null
and alternative hypotheses that the scientist should use for the
test? |
H0:μ is
|
less
than, less than or equal to, greater than, greater than or equal
to, not equal to, equal to |
7.3, 50,
1.7, 6.50 |
H1:μ is
|
less
than, less than or equal to, greater than, greater than or equal
to, not equal to, equal to |
7.3, 50,
1.7, 6.50 |
Assuming
that the actual value of µ is 6.50 pounds, what is the probability
that the scientist rejects the null hypothesis? Round your response
to at least two decimal places. |
|
What is
the probability that the scientist rejects the null hypothesis
when, in fact, it is true? Round your response to at least two
decimal places. |
|
Suppose that the
scientist decides to perform another statistical test using the
same population, the same null and alternative hypotheses, and the
same sample size, but for this second test the scientist uses a
significance level of 0.05 instead of a significance level of 0.01.
Assuming that the actual value of µ is 6.50 pounds, how does the
probability that the scientist commits a Type II error in this
second test compare to the probability that the scientist commits a
Type II error in the original test? |
|
The probability of
committing a Type II error in the second test is greater |
|
The probability of
committing a Type II error in the second test is less |
|
The probabilities
of committing a Type II error are equal |
|