WMES3103: INFORMATION RETRIEVAL

WEEK 10 : USER INTERFACES AND VISUALIZATION

User interfaces - communication betweeen human information seekers and IRS

When users approach an IRS - unclear as to how they can achieve their goal

User interface should:• Help to understand and express information

needs• Help formulate queries• Help select among available information

sources• Help understand search results• Helps monitor progress of search

HUMAN-COMPUTER INTERACTION 5 principles for the design of user

interfaces offer informative feedback permit easy reversal of action support an internal locus of control reduce working load memory provide alternative interfaces for novice

and expert users

DESIGN PRINCIPLESOffer informative feedback important for information access

interfaces system able to provide user with feedback

about : relationship between their query specification

and the documents retrieved relationship among retrieved documents, relationships between retrieved documents

and metadata describing collections

Permit easy reversal of action able to move back and forth

between screens icons – HOME, BACK

DESIGN PRINCIPLES

Support an internal locus of control if the user has control over how and

when feedback is provided, then the system is said to provide an internal locus of control

DESIGN PRINCIPLESReduce working memory load information access - iterative process goals change when information is found provide mechanisms to keep track of

choices made during the search process allowing users to return to temporarily abandoned strategies, jump from one strategy to the next and retain information and context across search sessions = HISTORY LIST

DESIGN PRINCIPLES provide browsable information that

is relevant to the current stage of the information access process – eg. suggestions of related terms or metadata, and search starting points including lists of sources and topic lists

DESIGN PRINCIPLES

Provide alternative interfaces for novice and expert users

simple interfaces – easier to learn, less flexible, less efficient use

powerful interfaces – allows a knowledgeable user to do more, more control over the operation of the interface, time consuming, a memory burden to occasional users

DESIGN PRINCIPLES use scaffolding technique – novice user =

simple interface that can be learned quickly, but expert user = alternative interfaces which give more control, more options, more features, etc

good user interface design = provides intuitive bridges between the simple and the advanced interfaces

how much information to show the user = a major design choice in information access interfaces

ROLE OF VISUALIZATION Tools of computer interface design –

windows, menus, icons, dialog boxes, etc – use bit-mapped display and computer graphics to provide a more accessible interface than command based display

Scientific visualization – maps physical phenomena onto 2 or 3-dimensional representations – eg. colorful image off the pattern and peaks on the ocean floor constructed from data only

ROLE OF VISUALIZATION Information visualization – humans highly

attuned to images and visual information – eg. remember a face from a picture much better than reading a written description of the same face -visualization of abstract information

Use language to communicate abstract ideas which has no physical manifestation – eg. how do we depict a picture whereby 2 parties are negotiating, one for concessions and the other not agreeing to it?

INFORMATION ACCESS PROCESS

1.       Start with an information need2.       Select a system and collection to search on3.       Formulate a query4.       Send query to the system5.       Receive results in the form of information items6.       Scan, evaluate, and interpret the results7.       Either stop, or8.       Reformulate the query and go to step 4

INFORMATION ACCESS PROCESS Information seeking process = standard

information access process or interaction cycle or simple interaction model

Used by Web search engines Does not take into account that most users

dislike to see long lists of retrieved documents that does not answer their query directly

Assumes user information need is static and information seeking process is one of successfully refining a query until it retrieves all and only those documents relevant to the original information need

STARTING POINT Search interface - must provide good

ways to get started Empty or blank screen does not provide

any clues to help a user decide how to start the search process

Users start with very short queries (testing) – inspect results – modify queries bit by bit

STARTING POINT Information access interface - must help

users select the sources and collection to search on lists of collections (CLJ) overviews ( contents of the collection, show

the topics represented within the collection and can help users select or eliminate sources – Yahoo)

examples/dialogs/wizards(provides examples of interaction with the system)

automated source selection (SavvySearch)

QUERY SPECIFICATION To formulate a query, the user must select

collections, metadata descriptions, or information sets against which the query is to be matched and must specify words, phrases, descriptors or other kinds of information that can be compared or matched against the information in the collection

The system will create a set of documents, metadata, or other information type that match the query specifications in some sense and display the results to the users in some form

QUERY SPECIFICATION 5 primary human-computer

interaction styles - command language, form filling, menu selection, direct manipulation and natural language

CONTEXT Various interface techniques for placing

the current document set in the context of other document types in order to make one document set more understandable

Showing the relationship of the document set to the query terms, collection overviews, descriptive metadata, hyperlink structure, document structure, and to other documents within the set.

CONTEXT Most common way to show results for a

query – list information about the documents in order of computed relevance to the query according to metadata attribute – document

title, date, source, length of article Ranking – numerical score or percentage Short or detailed view

Once, document is retrieved, good to highlight occurrence of search term with contrasting colour or reverse video

USING RELEVANCE JUDGEMENTS Important component of information

access process = query formulation Effective techniques for query formulation

= relevance feedback Standard interface for relevance feedback

consists of : List of titles with checkboxes beside the titles

that allow the user to mark relevant documents Unmarked documents = not relevant or no

opinion

USING RELEVANCE JUDGEMENTS

Marked = relevant OR Provide a choice among several checkboxes

indicating relevant or not relevant (with no selection implying no opinion)

OR Users put a value against each document to

mark level of relevance - issues a search command - system re-executes the search or generates a list of terms for the user to select to compliment original query - list of new titles appear

INTERFACE SUPPORT FOR SEARCH PROCESS User interface designer must make decisions

- how to arrange various kinds of information on the computer screen and how to structure the possible sequences of interactions

Simple interface - special purpose search window for string matching – FIND

More complex search tasks – interface designers must decide how to lay out the various choices and information displays within the interface – command or menu structure

INTERFACE SUPPORT FOR SEARCH PROCESS Windowing system – divide into different

simultaneously displayed views Able to link documents, cut and paste, Arrange information within windows –

monolithic display, tiled windows or overlapping windows

How many kinds of information can be shown at the same time – text display area as well as others eg. thesaurus terms, query specifications, lists of saved titles, etc.

Good layout, graphics, font size - IMPT

22 Jan 2004 Holiday Class will be cumulated with Week

12’s class HAPPY CHINESE NEW YEAR