statsexam3 10b

# statsexam3 10b - Economic Statistics Exam 3 Last name First...

This preview shows pages 1–4. Sign up to view the full content.

Economic Statistics Exam 3 Last name: June 14, 2010 First name: PID: Please sign that you abide by the honor pledge: This exam contains twenty short answer questions (worth 6 points each) and three long answer questions (worth 20 points each, unless otherwise noted). In all problems where you need to make a calculation, simplify your answer as much as possible. Show your work clearly to be eligible for partial credit. Some PDFs: Some probabilities: f ( x ) = 1 2 πσ 2 e ( X μ ) 2 2 σ 2 P [ x a ] = 1 e λ a f ( x ) = 1 u P [ x ] = λ x e λ x ! f ( x ) = λ e λ x P [ x ] = n ! x !( n x )! p x (1 p ) n x 1. Suppose that the random variable X is drawn from a normal distribution with a mean of 13 and a standard deviation of 3. What is the probability that X is between 11 and 17? 2. A researcher draws a random sample of size N = 16 from a normal distribution. His sample has a mean of 52 and a standard deviation of 6. Construct a 90% confidence interval for the population mean.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Econ 400 Midterm 3, page 2 of 9. 3. Suppose that you estimate Y as a function of two explanatory variables: Y i = β 0 + β 1 X 1 i + β 2 X 2 i + e i . In Stata, you type “ reg y x1 x2 ”: Source | SS df MS Number of obs = 1000 ---------+------------------------------ F( 2, 997) = 233.17 Model | 48166.9162 2 24083.4581 Prob > F = 0.0000 Residual | 102975.057 997 103.284912 R-squared = 0.3187 ---------+------------------------------ Adj R-squared = 0.3173 Total | 151141.973 999 151.293267 Root MSE = 10.163 -------------------------------------------------------------------------- y | Coef. Std. Err. t P>|t| [95% Conf. Interval] ---------+---------------------------------------------------------------- x1 | -1.570586 .3091338 -5.08 0.000 -2.177213 -.9639583 x2 | 4.546693 .2165667 20.99 0.000 4.121714 4.971671 _cons | 1.91043 .397595 4.80 0.000 1.130211 2.690649 -------------------------------------------------------------------------- What is the predicted value of Y for a person with X 1 = 10 and X 2 = 3 ? 4. In the previous question, test the hypotheses that both X 1 and X 2 have zero effect on Y (against the alternative that at least one has an effect) at the 95% confidence level. 5. I have an egg carton with 12 eggs; 4 are fresh, and 8 are rotten. If I select three eggs at random from the carton, what is the chance that all three are rotten?
Econ 400 Midterm 3, page 3 of 9.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern