ECON 203 Midterm 1
with correct questions
and answers
usr
[COMPANY NAME] [Company address]
,1. Which of he following about the Chi-squared distribution is FALSE
a. We use the Chi-squared distribution to perform a test on variance.
b. The Chi-squared is not symmetrical.
c. Only positive Chi-squared values are possible.
d. The Chi-squared distribution is asymptotic to the horizontal axis to
the right.
e. 1 is an approximation to the center of the distribution. Answer: e. 1 is
an approximation to the center of the distribution
REASON Answer: The center of Chi-squared distribution is approximated by its degrees of freedom minus
one.
2. Assume that the distribution of final scores of golf players at the
UC golf course is normal, with a standard deviation of 3 and a
median of 78. Consider that the par is 72, what percentage of
players score higher than the par? Answer: 97.5%
REASON Answer: In a normal distribution, the mean equals the median. We are interested in finding the
percentage of players scoring higher than 72. Given that 72 is 2*σ to the left of the mean, we know that
the area to the left of 72 will be
(1-.95)/2 = .025. The area to the right of 72 therefore is 1-.025=.975 or 97.5%.
3. You have just performed a hypothesis test with a 5% level of
significance. You have not rejected the null hypothesis that the
population mean is equal to 50 (H1 Answer: μj50). If you were to
create a 90% confidence interval, what could you say about 50
being included or excluded from that confidence interval?
a. The 90% confidence interval will include 50, since it is larger
than the 95% confidence interval.
b. The 90% confidence interval will include 50, since it is smaller
than the 95% confidence interval.
c. You are unsure if the 90% confidence interval includes 50,
because the 95% confidence interval contains 50.
d. The 90% confidence interval will not include 50, since it is
, smaller than the 95% confidence interval.
e. You are unsure if the 90% confidence interval includes 50, because
the 95% confidence interval does not contain 50. Answer: C. You are unsure if the
90% confidence interval includes 50, because the 95% confidence interval contains 50.
with correct questions
and answers
usr
[COMPANY NAME] [Company address]
,1. Which of he following about the Chi-squared distribution is FALSE
a. We use the Chi-squared distribution to perform a test on variance.
b. The Chi-squared is not symmetrical.
c. Only positive Chi-squared values are possible.
d. The Chi-squared distribution is asymptotic to the horizontal axis to
the right.
e. 1 is an approximation to the center of the distribution. Answer: e. 1 is
an approximation to the center of the distribution
REASON Answer: The center of Chi-squared distribution is approximated by its degrees of freedom minus
one.
2. Assume that the distribution of final scores of golf players at the
UC golf course is normal, with a standard deviation of 3 and a
median of 78. Consider that the par is 72, what percentage of
players score higher than the par? Answer: 97.5%
REASON Answer: In a normal distribution, the mean equals the median. We are interested in finding the
percentage of players scoring higher than 72. Given that 72 is 2*σ to the left of the mean, we know that
the area to the left of 72 will be
(1-.95)/2 = .025. The area to the right of 72 therefore is 1-.025=.975 or 97.5%.
3. You have just performed a hypothesis test with a 5% level of
significance. You have not rejected the null hypothesis that the
population mean is equal to 50 (H1 Answer: μj50). If you were to
create a 90% confidence interval, what could you say about 50
being included or excluded from that confidence interval?
a. The 90% confidence interval will include 50, since it is larger
than the 95% confidence interval.
b. The 90% confidence interval will include 50, since it is smaller
than the 95% confidence interval.
c. You are unsure if the 90% confidence interval includes 50,
because the 95% confidence interval contains 50.
d. The 90% confidence interval will not include 50, since it is
, smaller than the 95% confidence interval.
e. You are unsure if the 90% confidence interval includes 50, because
the 95% confidence interval does not contain 50. Answer: C. You are unsure if the
90% confidence interval includes 50, because the 95% confidence interval contains 50.
