CS 7280 Network Science Exam Practice
Questions And Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf.
1. Which statement best captures the central premise of network
science as taught in CS 7280?
A. The primary objective is to study individual entities independently of their
relationships.
B. Network science focuses exclusively on social networks and
communication graphs.
C. The structure and dynamics of relationships among entities can reveal
properties of complex systems that cannot be understood adequately by
studying the entities in isolation.
D. Network science replaces probability and statistics with deterministic
graph algorithms.
Rationale: Network science studies systems through interacting entities
and their relationships, emphasizing how topology influences system
behavior, dynamics, and function.
2. In an undirected network containing 1,000 vertices and 2,500 edges,
what is the average degree of the network?
A. 2.5
B. 5
,C. 1,250
D. 2,500
Rationale: In an undirected graph, the sum of all vertex degrees equals
twice the number of edges, so the average degree is
2m/n=2(2500)/1000=5.
3. Consider a directed network in which every edge represents a one-
way relationship. Which quantity measures the number of edges
entering a particular vertex?
A. Out-degree
B. Total degree
C. Betweenness
D. In-degree
Rationale: In a directed network, in-degree counts edges directed into a
vertex, whereas out-degree counts edges directed away from it.
4. A network contains several disconnected groups of vertices. Which
concept identifies a maximal set of vertices in which every pair of
vertices is connected by some path?
A. Clique
B. Cut set
C. Connected component
D. Independent set
Rationale: A connected component is a maximal subset of vertices such
that every pair is mutually reachable through paths within the component.
5. Why is the distinction between weighted and unweighted networks
important in network analysis?
A. Weighted networks cannot contain cycles.
B. Unweighted networks cannot contain directed edges.
C. Weighted networks encode additional information about the strength,
,distance, cost, frequency, or capacity associated with relationships.
D. Weighted networks necessarily contain more vertices.
Rationale: Edge weights allow network analysis to incorporate
quantitative properties of relationships rather than treating every edge as
identical.
6. Which statement correctly describes a directed acyclic graph (DAG)?
A. It is an undirected graph containing no triangles.
B. It is a directed graph containing no directed cycle.
C. It is a graph in which every vertex has equal degree.
D. It is a directed graph in which every pair of vertices has an edge.
Rationale: A DAG permits directed edges but prohibits any sequence of
directed edges that returns to its starting vertex.
7. A bipartite graph divides its vertices into two disjoint sets. Which
condition must hold?
A. Every vertex must have degree two.
B. Vertices within each set must all be connected.
C. Edges may connect vertices across the two sets, but no edge connects
two vertices within the same set.
D. Every vertex in one set must connect to every vertex in the other.
Rationale: Bipartite structure requires that every edge have one endpoint
in each of the two vertex partitions.
8. In a network, a path from vertex A to vertex B has three edges. What
is the path length under the standard unweighted definition?
A. 2
B. 3
C. 4
D. It depends on the number of vertices in the graph.
, Rationale: In an unweighted network, path length is normally the number
of edges traversed, so a three-edge path has length three.
9. Which statement best characterizes a random walk on an unweighted
graph?
A. At every step, the walker must move toward the highest-degree vertex.
B. The walker may traverse only edges that have never previously been
used.
C. At each step, the walker selects among the neighboring vertices
according to the specified transition probabilities, commonly uniformly in
an unweighted graph.
D. The walker must return to its starting vertex after every step.
Rationale: A standard random walk chooses the next vertex
probabilistically from the current vertex's neighbors, with uniform
selection being common for unweighted graphs.
10. Why is the maximum-flow/minimum-cut theorem important in
network science?
A. It proves that every network is connected.
B. It determines the average degree of a graph.
C. It establishes that the maximum amount of flow that can be sent from a
source to a sink equals the capacity of a minimum source-sink cut.
D. It guarantees that every graph has a Hamiltonian cycle.
Rationale: The max-flow/min-cut theorem connects an optimization
problem involving network flow with a structural partition of the network.
11. A network has 10 vertices and 15 undirected edges. What is its
average degree?
A. 0.67
B. 1.5
C. 3
D. 15
Questions And Correct Answers
(Verified Answers) Plus Rationale 2027
Q&A| Instant Download Pdf.
1. Which statement best captures the central premise of network
science as taught in CS 7280?
A. The primary objective is to study individual entities independently of their
relationships.
B. Network science focuses exclusively on social networks and
communication graphs.
C. The structure and dynamics of relationships among entities can reveal
properties of complex systems that cannot be understood adequately by
studying the entities in isolation.
D. Network science replaces probability and statistics with deterministic
graph algorithms.
Rationale: Network science studies systems through interacting entities
and their relationships, emphasizing how topology influences system
behavior, dynamics, and function.
2. In an undirected network containing 1,000 vertices and 2,500 edges,
what is the average degree of the network?
A. 2.5
B. 5
,C. 1,250
D. 2,500
Rationale: In an undirected graph, the sum of all vertex degrees equals
twice the number of edges, so the average degree is
2m/n=2(2500)/1000=5.
3. Consider a directed network in which every edge represents a one-
way relationship. Which quantity measures the number of edges
entering a particular vertex?
A. Out-degree
B. Total degree
C. Betweenness
D. In-degree
Rationale: In a directed network, in-degree counts edges directed into a
vertex, whereas out-degree counts edges directed away from it.
4. A network contains several disconnected groups of vertices. Which
concept identifies a maximal set of vertices in which every pair of
vertices is connected by some path?
A. Clique
B. Cut set
C. Connected component
D. Independent set
Rationale: A connected component is a maximal subset of vertices such
that every pair is mutually reachable through paths within the component.
5. Why is the distinction between weighted and unweighted networks
important in network analysis?
A. Weighted networks cannot contain cycles.
B. Unweighted networks cannot contain directed edges.
C. Weighted networks encode additional information about the strength,
,distance, cost, frequency, or capacity associated with relationships.
D. Weighted networks necessarily contain more vertices.
Rationale: Edge weights allow network analysis to incorporate
quantitative properties of relationships rather than treating every edge as
identical.
6. Which statement correctly describes a directed acyclic graph (DAG)?
A. It is an undirected graph containing no triangles.
B. It is a directed graph containing no directed cycle.
C. It is a graph in which every vertex has equal degree.
D. It is a directed graph in which every pair of vertices has an edge.
Rationale: A DAG permits directed edges but prohibits any sequence of
directed edges that returns to its starting vertex.
7. A bipartite graph divides its vertices into two disjoint sets. Which
condition must hold?
A. Every vertex must have degree two.
B. Vertices within each set must all be connected.
C. Edges may connect vertices across the two sets, but no edge connects
two vertices within the same set.
D. Every vertex in one set must connect to every vertex in the other.
Rationale: Bipartite structure requires that every edge have one endpoint
in each of the two vertex partitions.
8. In a network, a path from vertex A to vertex B has three edges. What
is the path length under the standard unweighted definition?
A. 2
B. 3
C. 4
D. It depends on the number of vertices in the graph.
, Rationale: In an unweighted network, path length is normally the number
of edges traversed, so a three-edge path has length three.
9. Which statement best characterizes a random walk on an unweighted
graph?
A. At every step, the walker must move toward the highest-degree vertex.
B. The walker may traverse only edges that have never previously been
used.
C. At each step, the walker selects among the neighboring vertices
according to the specified transition probabilities, commonly uniformly in
an unweighted graph.
D. The walker must return to its starting vertex after every step.
Rationale: A standard random walk chooses the next vertex
probabilistically from the current vertex's neighbors, with uniform
selection being common for unweighted graphs.
10. Why is the maximum-flow/minimum-cut theorem important in
network science?
A. It proves that every network is connected.
B. It determines the average degree of a graph.
C. It establishes that the maximum amount of flow that can be sent from a
source to a sink equals the capacity of a minimum source-sink cut.
D. It guarantees that every graph has a Hamiltonian cycle.
Rationale: The max-flow/min-cut theorem connects an optimization
problem involving network flow with a structural partition of the network.
11. A network has 10 vertices and 15 undirected edges. What is its
average degree?
A. 0.67
B. 1.5
C. 3
D. 15
