# Big Data Computing Assignment 8 Answers 2021

Big Data Computing Assignment 8 Answers 2021:- We do not claim 100% surety of answers, these answers are based on our sole knowledge, and by posting these answers we are just trying to help students, so we urge do your assignment on your own.

Q1. Which of the following are provided by spark API for graph parallel computations:

i. joinVertices

ii. subgraph

iii. aggregateMessages

(A) Only (I)

(B) Only (i) and (ii)

(C) Only (ii) and (iii)

(D) All of the mentioned

Ans:- (D) All of the mentioned

Q2. Which of the following statement(s) is/are true in the context of Apache Spark GraphX operators ?

S1: Property operators modify the vertex or edge properties using a user defined map function and produces a new graph.

S2: Structural operators operate on the structure of an input graph and produces a new graph.

S3: Join operators add data to graphs and produces a new graphs.

(A) Only statement S1 is true

(B) Only statement S2 is true

(C) Only statement S3 is true

(D) All of the mentioned

Ans:- (D) All of the mentioned

Q3. True or False ?

The outerJoinVertices() operator joins the input RDD data with vertices and returns a new graph. The vertex properties are obtained by applying the user defined map() function to the all vertices, and includes ones that are not present in the input RDD.

(A) True

(B) False

Ans:- (A) True

Q4. Which of the following statement(s) is/are true ?

S1: Apache Spark GraphX provides the following property operators – mapVertices(), mapEdges(), mapTriplets()

S2: The RDDs in Spark, depend on one or more other RDDs. The representation of dependencies in between RDDs is known as the lineage graph. Lineage graph information is used to compute each RDD on demand, so that whenever a part of persistent RDD is lost, the data that is lost can be recovered using the lineage graph information.

(A) Only S1 is true

(B) Only S2 is true

(C) Both S1 and S2 are true

(D) None of the mentioned

Ans:- (C) Both S1 and S2 are true

Q5. GraphX provides an API for expressing graph computation that can model the __________ abstraction.

(B) Pregel

(C) Spark Core

(D) None of the mentioned

Ans:- (B) Pregel

Q6. Match the following:

A. Dataflow Systems       i. Vertex Programs
B. Graph Systems         ii. Parameter Servers
C. Shared Memory Systems      iii. GuineaPig

(A) A:ii, B: i, C: iii

(B) A:iii, B: i, C: ii

(C) A:ii, B: iii, C: i

(D) A:iii, B: ii, C: i

Ans:- (B) A:iii, B: i, C: ii

Q7. Which of the following statement(s) is/are true in context of Parameter Servers.

S1: A machine learning framework

S2: Distributes a model over multiple machines

S3: It offers two operations: (i) Pull for query parts of the model (ii) Push for update parts of the model.

(A) Only statement S1 is true

(B) Only statement S2 is true

(C) Only statement S3 is true

(D) All of the mentioned

Ans:- (D) All of the mentioned

Q8. What is the PageRank score of vertex ‘B’ after the second iteration? (Without damping factor)

Hint:- The basic PageRank formula is:

Where, PRt+1(u)PRt+1(u) : page rank of node uu under consideration, PRt(v)PRt(v) : previous page rank of node ‘vv’ pointing to node ‘uu’ , C(v)C(v): outgoing degree of vertex ‘vv’

(A) 1/6

(B) 1.5/12

(C) 2.5/12

(D) 1/3

Ans:- (A) 1/6

Big Data Computing Assignment 8 Answers 2021:- We do not claim 100% surety of answers, these answers are based on our sole knowledge, and by posting these answers we are just trying to help students, so we urge do your assignment on your own.