Midterm1_Spring2007

# Midterm1_Spring2007 - ECO 230 Economic Statistics Marianna...

This preview shows pages 1–3. Sign up to view the full content.

ECO 230 Marianna Kudlyak Economic Statistics Spring 2007 MIDTERM EXAM I You have 1 hour and 15 minutes to complete this exam. Write your answers as clearly and concisely as possible. You may use the calculator the instructor has provided for you to add and multiply (please return it at the end of the exam). You may not use your own calculator. You may not use any books or notes. Make sure to show your reasoning and your work. There are 6 problems. Total 100 points. Selected formulas are provided for you on the last page of the exam.

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

View Full Document
Problem 1. [20 points] State which the following statements are true and which are false? (No explanation needed; just state “True” or “False”) 1.1.The time it takes you to write a test is an example of categorical variable. 1.2.If two random variables X and Y are independent, then P ( y | x ) = P ( x ) and P ( x | y ) = P ( y ). 1.3.The following data represent a sample of 10 scores on a statistics quiz: 16, 16, 16, 16, 16, 18, 18, 20, 20, and 20. After the range was calculated for the scores, it was discovered that one of the scores of 20 should have been a 21. The discovery of the mistake will not change the previously calculated value for range. 1.4.Chebychev’s Theorem states that for any population with mean μ and standard deviation σ , and k>1, the percent of observations that lie within k standard deviations from the mean is at most 100(1/k 2 )%. 1.5.If event A and event B are mutually exclusive and collectively exhaustive, then the complement of event A is identical to event B. 1.6.Events A and B are said to be statistically independent if the intersection of event A
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 5

Midterm1_Spring2007 - ECO 230 Economic Statistics Marianna...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online