University of Pennsylvania

What would you like to see change in terms of how evaluation is currently carried out in the social sector?

1. Consider an economy described by the Specific Factors model. The economy produces manufactures and food. Manufactures are produced with labor and capital, while food is produced with labor and land. Thus, labor is the mobile factor. Suppose this economy experiences a large immigration (i.e., an increase in its labor force). Assume that prices of manufactures and food are unaffected by the inflow of workers. Graphically argue what happens to output of manufactures, output of food, the ratio of these two outputs, wages, income of capitalists, and income of landowners.

Netflix has been tracking your watch history, as we know,
and has curated a list of 2n films that you are likely to enjoy: two films from each of your n
most-watched film genres. Netflix will only recommend four films to you at a time (this is
a gross simplification for the sake of the problem2). Thus Netflix will randomly select four
of the 2n films and show them on your homepage. Call these four randomly selected films
your “recommended sample.” What is the probability that
(a) there are no two films from the same genre in your recommended sample?
(b) at least two of the films in your recommended sample share the same genre?
(c) your recommended sample only features two different film genres?

You are the owner of an ice cream shop and you wish to offer a new, highly-
favored flavor. You create a list of ten different ice cream flavors that you can reasonably
offer and ask the next four customers to select their preferred flavor from the list. Suppose
that the probability of preferring any flavor on the list is equally likely.
(a) Let S be the sample space of this experiment. What is the cardinality of S?
(b) What is the probability that all four customers will prefer the same flavor?
(c) What is the probability that no two of these four customers will prefer the same
flavor?
(d) What is the probability that at least two of these four customers will prefer the same
flavor?
(e) What is the probability that the first two customers will prefer flavors 1 and 2 on
the list (in either order)?
(f) What is the probability that exactly three of the customers will prefer the same flavor
and the other customer will prefer another?
Hint: Consider keeping track of which customer prefers the unique flavor. Then the
preference of the other three customers will be known automatically.

A local hospital plans to form an ethics committee consisting of six individuals
that are randomly chosen from the thirteen employees on staff: 6 doctors, 4 pharmacists,
and 3 lawyers.
(a) How many different committees can they form in total?
(b) What is the probability that the committee they form will not contain any doctors?
(c) After our work in part (b), the hospital realizes that randomly selecting 6 individuals
from the thirteen employees could result in an imbalance. Instead, they decide to
randomly select 2 doctors, 2 pharmacists, and 2 lawyers from the employees on staff
(that is, 2 of the 6 doctors, 2 of the 4 pharmacists, and 2 of the 3 lawyers). How
many different committees can the hospital form using this new scheme?

(d) Suppose two of the six doctors do not support the hospital’s practices. What is the
probability that these two doctors will be the two doctors selected for the committee?
Note that the hospital is using the scheme described in part (c) here.

Suppose you bought three shares of RAFA on January 1 at a price of $64 per share. You subsequently sold one share at $69 a year later on January 1, and sold the other two shares a year after that for $62 each. At the same time, at the end of every year on December 31, shares of RAFA paid $3 dividend per share. What is your dollar-weighted or internal rate of return on this two-year investment? Round off your answer to four digits after the decimal point and state your answer as a percentage rate (i.e. 1.2345% as 1.2345)