Name:___________________________________ Date:
____________
Quiz 9
- Each semester every student is assigned to one of three
states. The student has normal status (N) if all is well. The student is
assigned probationary status (P) if the previous semester's grades are poor.
The student is suspended (S) for a semester if grades are not improved while
on probation. We assume that students always return to normal status after a
semester of being suspended. The probabilities observed are N-N = 2/3, N-P =
1/3, P-N = 1/2, P-S = 1/2, and S-N = 1.
a. Draw directed graph for the
relation M
on three vertices N, P, and S
using the
probabilities listed for each state change.
b. Find the in-degree and
out-degree of each vertex in
M.
List any
sources or sinks.
c. Fill in the weighted adjacency matrix,
M,
representing this Markov chain.

d. Find M2.
e. What is the chance that a student
with normal status will be in S (suspended status)
after two
semesters?

f. Given
M∞,
what is the long term probability that a student will
achieve N
status? ...S status?