DOCUMENT RESUME

-ED 078 673 EM 011 217

AUTHOR Lyman, Elisabeth R.TITLE An On-Line Document Retrieval Strategy Using the

PLATO System.INSTITUTION Illinois Univ., Urbana. Computer-Based Education

Lab.SPONS AGENCY Joint Services Electronics Program, Fort Monmouth,

N.J.; National Science Foundation, Washington,D.C.

REPORT NO CERL-R-X-21PUB DATE- May 71 =

NOTE 17p.

EDRS PRICE _ MF-$0.65 HC-$3.29DESCRIPTORS *Computers; *Information Retrievc..4.; *Information

Systems; *Man Machine Systems; *On Line-Systems;Program Descriptions

IDENTIFIERS

ABSTRACT

Coding Theory; *PLATO Computer Assisted InstructionSystem

A user - oriented computer - based information retrievalsystem which would not require a computer specialist as an interfacebetween computer and user was developed._The PLATO system was chosenbecause it was a high-speed computer-based man-machine interactionSystem with convenient visual display, keyset input device, versatileprcgraming-capability, time-shared on-line editing capability, and alogical program structure of interconnecting units._Coding Theory wasselected as the subject area in which the example was carried out.Tim retrieval kogram developed allowed searchers to make queries andreceive answers at the terminal, using a simple udialogueu logicProgram. Highly structured query paths leading to the data base werebuilt, although the ultimate system goal will be to have naturallanguage capability. The model retrieval system was successfulbecause it provided rapid responses, fostered simple user-computerlinteractions, permitted expansion of user questions, allowedalgorithmic functions to be employed, and stored a history of=interrogatory events for use in the subsequent modification of tl)eretrieval strategy. (PB)

AN ON-LINE DOCUMENTRETRIEVAL STRATEGY USINGTHE PLATO SYSTEM

AN ON-LINE DOCUMENT RETRIEVAL STRATEGY USING THE PLATO SYSTEM*

Elisabeth R. Lyman

Computer-based Education Research Laboratoryand

Coordinated Science Laboratory

U.S. DEPARTMENT OF HEALTH,EDUCATION 81 WELFAREOFFICE OF EDUCATION

THIS DOCUMENT HAS BEEN REPRO.DUCED EXACTLY AS RECEIVED FROMTHE PERSON OR ORGANIZATION ORIG.INATING IT. POINTS OF VIEW OR °PINIONS STATED DO NOT NECESSARILYREPRESENT OFFICIAL OFFICE OF EDU-CATION POSITION OR POLICY,

*This work was supported in part by the Joint Services ElectronicsProgram (U.S. Army, U.S. Navy, and U.S. Air Force) under ContractDIMS-07-67-0-0199, in part by the University of Illinois, and inpart by the National Science Foundation under grant NSF GJ 974.

A preliminary experiment is reported using the computer-assisted

instructional techniques of the PLATO teaching system for retrieval of

bibliographic references linked to a data base model in the subject ar

iii

ACKNOWLEDGMENTS

Appreciation should be expressed.tc many persons in both the

Computer-based Education Research Laboratory and in the Coordinated

Science Laboratory for suggestions which helped the development of

the PLATO retrieval strategy described in this report. These persons

include: Dr. Robert T. Chien, Dr, Franko Preparata, Mr. Williad Golden,

Mr. David Meller, and Mr. Paul Tenczar.

Thanks are due also to Jean Ciesa and Terry Gabrielse for their

-help with the publication.

AN ON-LINE DOCUMENT RETRIEVAL STRATEGY USING THE PLATO SYSTEM

Introduction

There are many computer-based information systems in existence or=

in the process of being developed. These systems offer considerable

assistance to the researcher in need of information which has appeared

in a myriad of professional journals and monographs.- Existing retrieval

systems, however, ordinarily require specialists who serve as an interface_

between the researcher and the computer because the operation of the systems

require skill in computer retrieval techniques. The use of computer-assisted

_instructional techniques- suggests itself .2.s _a-means _of _facilitating AnforMation

retrieval for the researcher or user unskilled in computer retrieval-. This

paper describes a preliminary application of CAI to the retrieval of bibliog-

raphic references-.

PLATO System

The PLATO computer-based teaching system provides an excellent= tool:1°r

developing__user-oriented strategies for -document _retrieval The PLATO system-I

is a high-speed computer-based man-machine interaction system with a convenient

_visual display, keyset input device, and versatile programming capability-in-

2cluding a simple -programtning language (TUTOR) , a time-shared on-line editing

capability, and a logical program structure of interconnecting units particularly

applicable to the "pathfinder" patterns helpful for retrieval. In addition,

another software feature, a dialogue logic, developed for PLATO by Mr. Paul

Tenczar, author of the TUTOR language, facilitates even further the design and

writing of retrieval programs. Authoring in "dialogue" is very simple, computer-

stored information is efficiently packed, and the dictionary of acceptable phrases

and words, which can be expanded at any time, can contain conveniently designated

The subject area, Coding Theory, in which the example of retrieval

was carried out, was chosen because a data base model for this area had

been reported in a paper on a "Relational Structure for Document Retrieval

in Coding Theory" by Nicholas Matthews Faser, Jr.4

and an implementation

The model for the subject area of coding theory, as structured by

Esser, was initially subdivided into seven steps which included all the

-coding theory topics from a decision to transmit information in coded form

tree -hierardhy

_k-re-al_-data;-batedof --dOctnaerit references-thtri-evable bylleyword- or

z-=--descriptor search-vas-not -used-in--tn-e_=rPLATO__ rStrieval-iexperiment-,--bta:=rathsr

arbitrary index numbers were assigned to each = point= =in the retrieval so that

ach reference request could be-identified_. For purposes of illustration

ever, real references were obtained and appear at the appropriate places

in the illustrative figures in this report as if they had been retrieved by

indexing or keyword search.

-3-

A Sample Retrieval

A PLATO retrieval program should allow a person searching for

bibliographic references to -make queries and get satisfactory responses

_- from a PLATO terminal. Such a program has been written using the PLATO

"dialogue" logic in which the document searcher can interact with-the=

computer to determine paths leading -to- retrieval of-relevant-reierenceS.7

A= description of a sample retrieval follows.

The user first specifies the general field 5f his search, in this

case, Coding- Theory, -(Figures 1-3) :

1

-4-

In order to _pinpoint- hiS request- he must first choose one of the seven-

J,!

ure

aracter

ebther----Of given --= various -alterriative-s---from==which

icnekit_ i(rigut4_

=

_

=

Since he is unsure o

Figure 12

=

_memor=y_ essnCIS Anne

references available here, an-so he -prOSSOS-DATA to -see - -the -l=ist of refeTences-

from which he can then -ice appropxkatt motes Vtgure 15)

Figure 15

-The user decides to follow urther (Figures 16- 1,-res-ses=

NEM returns to figure- 1 -types_ and procee

mna ti.o dlistreteyi 6.01tude contInuokm

Prrnw to reArr,v- pal

p,,,, LdTA to e-tke.

EigureLJ

1

0,5

rovflt,,ie eirwi tipe c115kTete

1) Or Ve,/P 015.35 - et- to rewKe pnr,,

Pre-N-5 -DATA- to

4

i ure 18

0-4,.. dis_--_rvii-

Figure 20 igure 21

Finding himself at the end of the query path, he presses DATA and again

gets some references (Figure 22):

Figure 22

Here he not= ices-a legend in the upper righthand corner of his screen:

TED TOPICS. The legend indicates he might find further references in

ome other branch of the coding theory subject matter which also deal with

sa=es_ e path he initially followe

PATHtwinflui eyndf-1,

vwfd

empiltude aftl disxr

rrast,rt- chnnnel

=owing the

nodel" path (PATH 1, Figure 21),he decides=

area cnce.moreH_ _lx_ress_esSHIET=an

eeub_topics

tp t4 t tt

-i0-

Figure 30 Figure 31

The computer does not recognize his query as phrased, hut he tries rephrasing

and this time can get references for this adda tiona rv (Figures 32-35):

Figure 32 Figure 33

IL:

__:&atisfied_witiv_the-respenee_tozhis "free aelte"_xeluest, the searcher

response to natural language queries through some mechanism such ellMpttetc

system terminal. It seems logical, however, to work out some stru=cture

--atechniquesfirst. It should be noted againmthat4n

determinem organization and search of a real data bas

here isonly concerned with an illustration of user query techni-que

vanta-6SEOfthe_PLA ORSystem for user interrogatiorva

Stem

time=sav_ 111-euser. -ond:fthePLATO "dialogue'" is _convenient _

anotathinem nte-notionsprogtAfts for muSermteohnigutmexploratiOnaV ic

=milloremStWAf:Ant techniques= thanthe usual PLATO.TUTORqft_gmatn

questions mrstrievams stemmsow _respon mwhenevermussr

mmqueriesms owmp rasesmarowardsmwhic were -not _originall

-13-

=74appropriate algorithms, -hased7_on' lateral- and:vertical relationship's in _

hierarchy, to he -substi tUted__ far ,precalc'ulated- linkages-- so that the

--couldu:generate: query-levels-as-Veil -7as" links- to---related tool.

th-,1- _the -IPLATO' :diaiogue_,techniveallows=:a==historyof eventsf_occurring_

uring:- the- tours the inter=rogation °to be stored iwrniemory _during iv_ ery_=7=i

ich_ =may - then_ used at--aubse-quentmo-dififcationoLlt et-retrieval_ stra_te

e iadvenV_o-f=th'e tlargez--aca e_syat

rincipally dedice_ted= o teachin

-BIBLIOGRAPHY