Final

Question 1

What is cross-sectional Data?

Answer 1

Data measured at one point in time. The
variation is the units of observation

Question 2

What is Time Series Data?

Answer 2

One variable that is measured over a period of time.
The variation is time.

Question 3

What is Pooled Cross-Sectional Data?

Answer 3

Combines aspects Cross-Section and
Time Series data. The variation is time and the units of observation.
Note that the same units don’t need to be measured at each point in
time.

Question 4

What is Panel Data?

Answer 4

Combines aspects of Cross-Section and Time Series data.
The variation is time and the units of observation. The same units need
to be measured at each point in time.

Question 5

In homeworks 1, 2, and 5, we used the housing.xls data set, a
sample of 88 houses in Boston in 1990. What type of data set
is this?
A Panel
B Time Series
C Pooled Cross-Sectional
D Cross-Sectional

Answer 5

D Cross-Sectional

Question 6

Suppose 30% of the women in a class received an A on the test
and 25% of the men received an A. The class is 60% women.
Given that a person chosen at random received an A, what is
the probability this person is a woman?
A 0.18
B 0.28
C 0.64
D 0.10

Answer 6

C 0.64

Question 7

How do you find P(W|A)?

Answer 7

P(W | A) = P(W ∩ A)/P(A)

Question 8

What about P(W ∩ A)?

Answer 8

P(W ∩ A) = P(A | W )P(W )

Question 9

Four witnesses, A, B, C, and D, at a trial each speak the truth
with probability 1
3 independently of each other. In their testi-
monies, A claimed that B denied that C declared that D lied.
What is the (conditional) probability that D told the truth?
Hint: In this problem, two lies do in fact make a truth. Thus,
if two people lie, the conclusion will be that D told the truth.
A 13/41
B 13/81
C 1/3

Answer 9

A 13/41

Question 10

What are the parameters of a Binomial Distribution?

Answer 10

Parameters n and p

Question 11

What are the parameters of a Geometric Distribution?

Answer 11

Parameter p

Question 12

What are the parameters of a Poisson Distribution?

Answer 12

Parameter λ

Question 13

What are the parameters of a Normal Distribution?

Answer 13

Parameters μ and σ2

Question 14

What are the parameters of a T-Distribution?

Answer 14

Parameters “Degrees of Freedom”

Question 15

What Distributions are discrete?

Answer 15

Binomial, Geometric, and Poisson.

Question 16

What does a Binomial variable represent?

Answer 16

the probability of x successes in n trials

Question 17

Under Assumptions OLS1-OLS3 estimators are _____

Answer 17

unbiased

Question 18

Under Assumptions OLS1-OLS4, the OLS estimators are

Answer 18

normally distributed when n is large,
Bjhat ~ N(Bj, Var(Bjhat)

Question 19

Under assumptions OLS1-OLS5,_______

Answer 19

Prediction intervals can be computed

Question 20

Under Assumptions OLS1-OLS4, the OLS estimator is the (BLUE)_______

Answer 20

Best linear unbiased estimator

Question 21

Uhati = Yi − bYi
= Yi − bβ0 − bβ1Xi