Unit 5 - Web Searching

Question 1

Data structures used for storing indices:

Answer 1

1. Suffix tree,
2. Inverted index
3. Citation index
4. N-gram index
5. Term document matrix

Question 2

What are indices?

Answer 2

Indices are nothing but short descriptions of each webpage that may include title, creation, date and size, 1st line etc.

Question 3

What is XML?

Answer 3

Stands for extensible Markup Language, used for exchanging data on the Web

Enables separation of content(XML) and presentation(XSL).

Question 4

Who created XML?

Answer 4

W3C, to provide easy to use and standardised way to store self describing data.

Question 5

INEX 2002 defined:

Answer 5

Component coverage and topical relevance

Question 6

Four cases in Component coverage dimension

Answer 6

Exact coverage (E)
Too small (S)
Too large (L)
No coverage (N)

Question 7

Cases in Topical relevance:

Answer 7

Highly relevant (3)
Fairly relevant (2)
Marginally relevant (1)
Non relevant (0)

Question 8

What is a search engine?

Answer 8

Search engine is a program which helps users to find information stored on a computer somewhere in the World Wide Web.

Question 9

Centralised crawler index architecture:

Answer 9

It is used by most of the search engines so it uses a crawler gather information to a single site where it is index by the index

Question 10

Components of crawler indexer architecture

Answer 10

Crawlers, index query engine user interface

Question 11

Problems using crawler indexer architecture

Answer 11

Dynamic nature of the web
High load on web servers
Large volume of data
Communication link problem

Question 12

Harvest distributed crawler index and architecture

Answer 12

Problems:
Due to different crawler server load increase
Object by the cross are usually useless and discarded
No coordination among the crawlers

Question 13

Components of harvest:

Answer 13

Gatherers
Brokers
Replicator
Object cache