Description
Question 1 [10 marks]
“Social networks have developed rapidly in recent years. According to eMarketer’s
forecast, the total number of social Internet users in China will increase by 4.8% in
2020, reaching 859.1 million.
The peak volume of Sina Weibo posts reached a new high.
At 0:00:00 during the Chinese New Year in 2020, a total of 32,312 Weibo posts were
posted simultaneously.”
Please specify which Vs in 4V are reflected in the text above and explain the reason in
detail. [10 marks]
Question 2 [15 marks]
Consider an imaginary web of 3 web pages, as shown in the figure below:
Assume that the initial page rank of each web page is 1 and the damping factor is 0.5.
a) Calculate the page rank values of A, B, C for the first three iterations. Approximate
the results to 3 decimal places. [5 marks]
b) If the approximate page rank values stay unchanged in iterations, we consider that
the page rank values reach convergence. Write the number of iterations required for
page rank values to converge and give the final page rank values for A, B, and C.
(Programming is encouraged) [5 marks]
c) The following graph illustrates the process of PageRank algorithm in MapReduce
framework. Calculate the intermediate result with calculation process. [5 marks]
Question 3 [25 marks]
Extracting part of the census data, we can get the following child-parent relationship
table:
Child Parent
Tom Lucy
Tom Jack
Jone Lucy
Jone Jack
Lucy Mary
Lucy Ben
Jack Alice
Jack Jesse
Terry Alice
Terry Jesse
Philip Terry
Philip Alma
Mark Terry
Mark Alma
We need to use MapReduce to find the grandchild-grandparent relationship (example:
Tom-Mary) from this table.
a) Explain how you implement the map and reduce functions (including the key-value
pair definition) in pseudo code and show the intermediate results by each mapper
and the output by each reducer. (Using 2 mappers and 2 reducers, consider the rank
and shuffle module is predefined.) [15 marks]
b) Implement the map and reduce function using python language. And upload the
source code file. [10 marks]
