Econ 210 Winter 2009 First Midterm - Solutions

Econ 210 Winter 2009 First Midterm - Solutions -...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Northwestern University Department of Economics STAT 210 Introduction to Statistics - Professor: Steffen Habermalz First Midterm Examination – January 30 th 2009 INSTRUCTIONS : Please read the whole exam first. Questions are not ordered by difficulty. Answer all questions. Make sure you show ALL your work. Merely reporting the correct answer will not result in full credit. Write legibly. If we can’t read it, we won’t grade it. GOOD LUCK! 1. Write your name on the answer sheet. 2. (2+3=5 pts. each) True/False: State if the following statements are true or false. Only clearly explained answers earn full credit . a. The following is always true: P(C∩D 1 ) + P(C∩D 2 ) + P(C∩D 3 )=P(C) FALSE. While it looks like the law of total probability the statement is only true if the events D 1 -D 3 are exhaustive and disjoint. b. If E(X)=5 then E(X|Y)=5 FALSE. It’s the other way around. We know that due to the LIE we can write E(X)=E Y [E(X|Y)]. If E(X|Y)=5 this implies E(X)=5 but it is not true the other way around. c.
Background image of page 1

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

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 09/25/2010 for the course ECON 210 taught by Professor Pavan during the Winter '09 term at Northwestern.

Page1 / 3

Econ 210 Winter 2009 First Midterm - Solutions -...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online