Advanced SearchTechniques for Large Scale Data Analytics
Pavel Zezula and Jan Sedmidubsky
Masaryk University
http://disa.fi.muni.cz
 For the following graph
 Compute the PageRank of each page, assuming no
taxation
Pavel Zezula, Jan Sedmidubsky. Advanced Search Techniques for Large Scale Data Analytics (PA212) 2
BA
C
 For the following graph
1) Set up the PageRank equations, assuming β = 0.8
2) Order nodes by PageRank, from lowest to highest
Pavel Zezula, Jan Sedmidubsky. Advanced Search Techniques for Large Scale Data Analytics (PA212) 3
4 6
321
5
 For the following graph
 Assuming β = 0.8, compute the topic-sensitive
PageRank for the following teleport sets:
1) {A}
2) {A, C}
Pavel Zezula, Jan Sedmidubsky. Advanced Search Techniques for Large Scale Data Analytics (PA212) 4
BA
DC
 Suppose the BALANCE algorithm with bids of 0
or 1 only, to a situation where advertiser
 A bids on query words x and y
 B bids on query words x and z
 Both have a budget of $2. Decide whether the
following sequences of queries are certainly handled
optimally by the algorithm:
1) yzyy
2) xyyz
3) xyzx
Pavel Zezula, Jan Sedmidubsky. Advanced Search Techniques for Large Scale Data Analytics (PA212) 5
 Bookstore has enough ratings to use a more
advanced recommendation system
 Suppose the mean rating of books is 3.4 stars
 Alice has rated 350 books and her average rating is
0.4 stars higher than average users' ratings
 Animals Farm, is a book title in the bookstore with
250,000 ratings whose average rating is 0.7 higher
than global average
 What is a baseline estimate of Alice's rating for
Animals Farms?
Pavel Zezula, Jan Sedmidubsky. Advanced Search Techniques for Large Scale Data Analytics (PA212) 6
 Computers A, B and C have the following features:
 Assuming features as a vector for each computer, e.g., A’s
vector is [3.06, 500, 6], we can compute the cosine distance
between any two vectors
 Scaling dimensions can prefer some components
 Assume 1 as the scale factor for processor speed, α for the
disk size, and β for the main memory size and compute:
1) The cosines of angles between pairs of vectors (in terms of α and β)
2) The angles between the vectors if α = β = 1
Pavel Zezula, Jan Sedmidubsky. Advanced Search Techniques for Large Scale Data Analytics (PA212) 7
Feature A B C
Processor speed 3.06 2.68 2.92
Disk size 500 320 640
Main-memory size 6 4 6
 A user has rated the three computers as follows:
 A: 4 stars, B: 2 stars, C: 5 stars
 Tasks:
1) Normalize the ratings for this user
2) Compute a user profile for the user, with the
following features
Pavel Zezula, Jan Sedmidubsky. Advanced Search Techniques for Large Scale Data Analytics (PA212) 8
Feature A B C
Processor speed 3.06 2.68 2.92
Disk size 500 320 640
Main-memory size 6 4 6