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Artificial Intelligence and the SAS· System:
Why You Have To Teach the SAS· System about Sex!
David B. Malkovsky, SAS Institute Inc., Cary, NC
has been research in basic AI techniques, such as ways to represent
knOWledge. development of special programming languages (for
example, LISP, logic programming languages like Prolog, and
object-oriented programming languages), tools (expert systems
shells, for example), and architectures for AI applications.
ABSTRACT
This paper presents a very brief survey of the areas that comprise
artificial intelligence (AI) research (knowledge representation, natural language understanding. expert systems, and so on).
To date, the following kinds of AI applications have been developed:
The majority of the paper describes AI researCh done at SAS Institute and a new product, SAS/ENGLISW software, which is a result
of that research effort. SAS/ENGLISH software provides users with
a means of asking for information about their data by typing English
questions using a user-friendly interface that avoids a computerspecific language or syntax. The importance of knowledge acquisition to make this interface work is discussed. The subtitle of the
paper is used to draw attention to the need for teaching AI programs
the words and concepts that humans take for granted when they
query each other in normal conversation.
.. natural language interfaces to databases-interfaces that do
not require users to learn special command languages
.. expert systems-systems that use the knowledge of
specialists to perform tasks such as medical diagnosis,
chemical analysis, geological exploration, and computer
system configuration
.. automatic programming systems-systems to create
programs based on descriptions of what the programs
should acco.mpUsh
INTRODUCTION
• vision and robotic systems with sensory apparatus that
respond to changes in their environment
There is disagreement in the field of artificial intelligence (Al) as to
what constitutes the discipline. It is not unusual to find people who
believe they are working in the field of AI, but are not considered
to be doing so by any of their colleagues. Conversely, there are
other individuals working in areas that are traditionally considered
to be part of AI who refuse to apply that label to their work. In reading announcements of new products or advertisements in leading
computer periodicals, you are led to believe that almost everyone
in the computer field tOday is working on, or in, the AI field.
• neural network approaches to pattern recognition and
knowledge acquisition
• fuzzy logic approaches for performing inexact reasoning.
Such systems were developed for medicine, business, engineering,
SCience, and manufacturing applications.
Answers to the question of what constitutes AI often center on
defining the borders or limits of the field. One possible (and overly
simplistic) test for receiving the AI classification is that any program
written in LISP or Prolog belongs to the field of AI. Although in the
first half of the history of AI this was very true, it is no longer a necessary or sufficient test
The remainder of this paper will examine one specific AI application
from SAS Institute, SAS/ENGLISH software, which draws on a long
tradition of language processing and AI research.
Other litmus tests of AI-ness identify systems that use knowledge,
employ search techniques, have an inference engine, or modify their
behavior over time.
The function of a natural language interface such as SAS/ENGLISH
software is to provide easy access to data without the user's having
to learn the syntax of a retrieval language or know the structure and
field names associated with individual data values.
One humorous definition of AI states that ~ AI is any program or system that never gets to market" The basis of this view is that AI is
magic and complex. If a marketable product is produced, the problem it solves was never in the field of AI. Rather, the task solved
by such a system was only a complex software engineering task
that was ear1!er misclassified as an AI problem.
Using the full-screen interactive facility illustrated in Display 1, you
type your question and SAS/ENGUSH software provides your
answer. Once information is accessed, a user can use the full power
of the SAS" System to manage, analyze, and present the data without ever leaving the menu-driven environment
SAS/ENGLISH SOFTWARE
SAS/ENGLISH software works by translating a question into Structured Query Language (SOL) commands and presents the retrieved
data or answers in the SAS/ ASSIST" software environment
Obviously there is no one correct answer to the question ~What is
artificial intelligence?~ One acceptable answer is that AI ~is the part
of computer science concerned with designing intelligent computer
systems, that is, systems that exhibit the characteristics we associate with intelligence in human behavior - understanding language,
learning, reasoning, solving problems, and so on~ (Barr, Cohen, and
Feigenbaum 1989, p. 3).
SAS/ENGLISH software is a quick and easy way to get information
and generate reports. Users can find, order, and summarize data
by asking simple who, what, when, where, how many, and yes/no
questions.
MAJOR AI APPLICATIONS
The kinds of intelligent human behavior that AI investigators have
tried to simulate include deduction, vision, learning, planning, problem solving, and natural language understanding. In addition, there
341
SAS/ENGLISH: .BUqlhh Language
Query'-----------_~
range" job responsibilities, payroll status, and other job-related
accounting information. The relationship between employee object
and the job information must be defined to the SAS/ENGLISH KB
in order for questions about an employee's job to be answered.
Jnovltdge Base: ItBS.SUGI17
ItS DescrIption: ltnovledge Base for 8!1GI17
Pleue enter yOQT qu.... y,
Defining the Vocabulary
Presentation:
Optlon~:
• Lj$t1ng
o Report
The last function of KB administration is to define the vocabulary
and specify idioms that describe the data. Each application has a
SpecifiC vocabulary that is customarily used with the data accessed
by the application. In addition, the same data in different industries
or applications are often known by different names. For example,
people are commonly known as students in a school environment,
as employees in a corporate setting, and as subjects in medical
experiments.
X Run Generat"d' Cod'e
X ShoW Query l'ar.p~ra$"
X Show UIIknown Words
o Vie" t .. bUlar
o Brown c!>nrvaticn
o High resolution graphics
o LoW resolution graphics
<Addltlobd Options>
<RIJ1I>
Display 1
<Recall>
<Resnltn
<Gobacb
Objects, Attributes. and Relationships
<H.Ip>
SAS/ENGLISH Knowledge Base administration makes some very
important and fundamental assumptions about the data that it can
model. The data model is oriented toward recognizing objects (also
called entities), attributes of objects, and relationships between
SAS/ENGLISH English Language Query Screen
SAS/ENGLISH Knowledge Base
objects.
To understand a question or query, SAS/ENGLISH software uses
an information storage facility, or data model, called the Knowledge
Base (KB). The KB describes the data in terms of real-world concepts, relationships, and vocabulary. This type of information is cal·
led domain·s'pecific information. It includes the content, concepts,
and context of the data that do not exist in the. built-in Knowledge
Base of SAS/ENGLISH software. The activity of acquiring domainspecific information is known as knowledge base definition. The person who performs this task is the KB Administrator (KBA). The successful completion of this task requires an understanding both of
the purpose of the application and of how a typical user interacts
with that application.
An object corresponds to a concept or thing in the real world and
is represented by data in a data set. It can be a person, an event,
a physical object. or an organizational entity, such as a department
in a company. Objects or entities have attributes or characteristics.
For example, people have names, heights, and weights; and events
have times and places.
SAS/ENGLISH Knowledge Base Definition
The SAS/ENGLISH Knowledge Base Definition facility is a fullscreen SASIAF" software application that is used to interactively
define a Knowledge Base describing the data for a specific application. Before defining a KB, the data must be identified and made
accessible to SAS/ENGLISH software. This step may require defining SAS views or using a SAS/ACCESS product if the data are not
in native SAS data sets.
The effort required to provide a level of detail and coverage to successfully implement a complete SAS/ENGLISH KB is not triviaL
There are three major tasks of KB administration:
• creating the physical data model
• creating the conceptual data model
Defining a Knowledge Base is usually an iterative process. A KBA
begins with an initial model of the data, builds a Knowledge Base,
and then tests some sample queries. If the queries are not under~
stood, additional vocabulary may be needed or objects and their
attributes may need to be defined differently. In some cases, it may
be necessary to structure the data differently and redefine the
Knowledge Base.
• defining the vocabulary.
Creating the Physical Data Model
The first task of KB administration is to specify the name and location of the data files associated with the application. The applicationspecific data are stored in one or more data sets that can be
accessed by the SAS System. The physical location and storage
method are unimportant to the SAS/ENGLISH product, as long as
they are accessible by a native SAS engine or through a
SAS/ACCESS$ software product.
The first attempt at defining a KB is usually not the last because
it is nearly impossible to think of everything during the first session
of KB definition. Modifications and improvements of the KB are
always possible over the life of the application. Most decisions made
during the definition process are easily altered or reversed.
Creating the Conceptual Data Model
Sample SAS/ENGLISH Knowledge Base Definition
Having identified the particular data components of the application,
the second task is to specify what concept or object each data element represents. For example, if a particular employee data set is
a component of a human resource application, the employee data
set can be modeled by an employee object. If the user enterprise
is related to the sale of a product, a particular group of data may
represent the concept of a sales transaction.
This section of the paper will discuss various components of the
Knowledge Base definition process and present some of the interactive screens associated with each component.
Once a name and location for the Knowledge Base is chosen, the
Select Data Set screen, illustrated in Display 2, is the central point
for building the KB.
Part of identifying the objects or the concepts of an enterprise is
specifying the relationships between the various objects. Continuing
with the human resource example, a second data source may con-tain the job descriptions for the various positions within the company. The data file might not only include the job title, but the salary
342
SAS/EN~LISH'
S~l~ct
nata S e t - - - - - - - - - - - - - - - - - ,
SAS/EKGLISH, Define a Data
Defining- data nt
Choou a new [lata Set
Set'----------------~
P!~D"!A.J!HPLYEI
Sp*cHy n01lns to refer to
Specify verbs to uhr to
nefine spedal attributes
Set eptions fer this data
Set Other KB Option.
Sal"ct a data set that has already heen defined:
Clod
Data ut nam"
lIeference "ord
this data nt.
this d~ta set.
of this data $et.
set object.
lype ley? Punt? Sort? var? l'e"" .. t
Oef Cmd Attribute
.....
PHAIIl!
tll""!
~
~
SC1IAlI10.
SC1lAll20.
'"
-
~UX
_
_
00.
DATB1.
fflll~nAT1!:
OIlIS1.
SC1lAlI15.
SCUAR15.
_crn
..
_ _ ST"TE
_
_
<BrOl/un
Display 2
<Gobac:b
<Help>
<Help>
<oebu\J>
SAS/ENGLISH Select Data Set Screen
Display 4
This screen has options for adding new data sets to the Knowledge
Base (Choose a New Data Set button) and performing specialized
and advanced KB operations (Set Other KB Options button). The
Query option allows you to test queries to see the effects of adding
or deleting information from the KB. The Browser option lets you
examine the KB using the Knowledge Base Browser.
SAS/ENGLISH Define a Data Set Screen
The next level of specification is the definition of the type and use
of each variable in the data set. Fortunately, there are only two
groups into which attributes fall. They are based on the data type
of the attribute; the data are either numeric or character. For the
purpose of this discussion. we will k>ok at one example of each type.
SALARY and SEX are the attributes used here to represent numeric
and character type attributes, respectively.
As new data sets are added to the Knowledge Base, they are listed
with their corresponding main reference word. The main reference
word is the word that best describes the object represented by each
data set. This word is used by SAS/ENGLISH software instead of
the data set name to specify the object. A complex KB for a business application may look like the one shown in Display 3 below.
SAS/~n~LISH:
DOH"1111.2
SALAiI~
DlP'I'
After selecting the SALARY attribute on the Define a Data Set
screen, the next screen seen by the Knowledge Base Administrator
is the Define Numeric Attribute screen, as shown in Display 5 below.
SAS/!IIGLISU: Define 1I...... ri<: Attribut ...- - - - - - - - - - - - - - ,
Dsfinition of numeric variable SALAilT
1n data set PEII!!!IIA!A.EMPLU!
Select Oata S e t - - - - - - - - - - - - - - - - - ,
Koun used to rabr t(l this attribllte: SALAIlY
Choo~e
a lis" Data Set
Choose the but
(l A number that
A quantity of
a A measllrement
a " number that
o A time, date,
o A money value
°
Set Other KB options
Hlsct a data set that has already baen defined:
ClOd Oata set name
Reference I/ord
PERllDAlA.!IIPL'lBE
PE!IlIOATA.iIlGlllill
PEIUlDAU. SALESPIl
PBIlIlOAlA.DEPJ
P!IUIOAJA. IUK
P£IIHOAlA.CUJnfT
PBIIHOArA.SALE
PBIIHDAJA.PIIOJECJ
PEIIHDATA.PR.1'fIHE
UIIHDATA.i>RJUSE
EKPLOYEE
ducription of SALAIlY.
1dentH Ies i:IIPLOY~E.
EMPLOYBE.
of !HPLOY1!:H.
identifies an Object uiahd to EHPLOYEE.
or duration (If &IIPLOYEE.
associated I/ith HHPLOUE.
Specify nOllns to refar to 8FJ.ARY.
Sp$dfy verhs relating- SALARY to EHnOYu.
Specify conn&ctlon$ betlfeen SALAItY and illnOYHE..
Specify adjectives de.cribing E.IIPLOYSE by SAtAU.
Define clU. options for SALARY.
SALESPERSOII
OEPAUHEIIT
,,~
CLIENT
m.
PROJECT
"OU
""
<Gobacb
<Qllery>
Display 3
<BrOl/ser>
<GolJaek>
<Kelp>
Display 5
<Debug>
<Hall'>
SAS/ENGLISH Define Numeric Attribute Screen
In the middle of the screen, there are several general types of
numeric attributes from which the KBA must choose the best
description of the attribute. The selection of the description or type
adds information to the Knowledge Base as to how or where in a
query this data can be specified. The various numeric types are the
following:
SAS/ENGLISH Select Data Set Screen
The Select Data Set screen is the central point for specifying the
contents of the KB. The Define a Data Set screen is the central point
for defining the contents of each data file to SAS/ENGLISH software. The screen example in Display 4 below shows that much of
the information is similar to that produced by running the
CONTENTS procedure on the data set. Infonnation unique to
SAS/ENGLISH software includes specifying vocabulary, defining
special attributes, and setting object options.
a number that identifies the object
This type is chosen if the attribute uniquely specifies
or identifies the observation in the data set. For
those of you familiar with relational databases,
SAS/ENGLISH software assumes that such an
attribute forms a primary singleton key.
a quantity
This type is chosen if the attribute counts some
object.
343
for a compensation monetary attribute. A KBA can define
meaningful adjectives for this attribute by selecting Specify
adjectives describing EMPLOYEE by SALARY on the
Define Numeric Attribute screen. Making such a selection
results in the screen shown in Display 7:
a measurement
This type is chosen if the attribute measures or
rates some aspect of the object. Examples of this
type of attribute are temperature, age, and weight.
a number that identifies a related object
This type is chosen if the values of the attribute
identify some data set object other than the current
object. This type of attribute is sometimes known as
a join field.
5AS/KRGLISH: lIefine A d j e c t i v " . - - - - - - - - - - - - - - - - ,
IIt1l11eric attribute SALARY
.in d4t4 set PEIlHIIATA.EHPUU
hter ne .. adjectival
;>p~'"~"c---~"~,~"~".C----c"~,~,~""="~
a time, date, or duration
This type is chosen it the attribute represents a
time, date, or some length of time.
< Edit Range
_
_
_
_
•
_
_
_
_
Display 7
Choose one of the followin'1 that !>est describes th:is attribute:
EHP~OYBE.
A form of compellsation recuved by BHPLOYKE.
So.... other kind of money attribute of RIIPLOYEB.
Display 6
CHIAP
SLIH
FAT CAT
,"OOR
RICH
nDIOCRR
HODERATB
> 60000
<
>
>
>
10000
40000
20000 < 60000
30000 < 70000
<Help>
SAS/ENGLISH Define Adjectives Screen
This example Define Adjectives screen is already filled with
information specified by the KBA. For example, the words
EXPENSIVE, HOT, and FAT are equated with large salary
values, and the words CHEAP and SLIM are associated
with small data values. The KBA specified the root 10nn of
the adjectives because SAS/ENGLISH software
automatically recognizes both the comparative and
superlative tonns when they are used in queries. Thus the
KBA specified FAT rather than the comparative form,
FATTER, or the superlative form, FATTEST.
Ddin .. unit of ""asore for thh ,\tttibuh
<Gobad>
IIXPEIISIVE
FAT
<Gobacl<>
Definition of mOlley attribute aA~1JIY
111 data set PllUIDAT'\.iIII!PLYRR
A price of
< Othar option. >
_1I0T
Once the KBA selects one of these types as the primary
type description of the attribute, additional information may
be required to define more uniquely the use or scope of the
attribute. In this example, once the KBA specifies that a
money value is the best description of the attribute
SALARY, the screen shown below in Display 6 appears
requesting more specific information.
,\ttribute---------------~
Object Noun
c Clear ilord
Range
CiIld Dr lin ilord
a money value
This type is chosen if the attribute represents a price
of something or money received for services.
S,\S/IIfGLlSH: Honey
Add ilord
>
hn'i/$ defined:
The direction field (Plus, None, and Minus) is needed to
indicate the direction associated with a comparative data
value. In this example, the larger the data value, the higher
(or fatter, or hotter) the salary. If the attribute were age and
the data values were represented by a person's date of
birth, then the oldest person would be the person with the
smallest (or earliest) birth date (direction of minus).
<Help>
SAS/ENGLISH Money Attribute Screen
Money is usually the purchase price of some object or
service, or a form of compensation received by some object
or person. If the KBA selects price as the specialized type
of money attribute, the KB is automatically modified to add
the words PRICE, COST, and VALUE as synonyms for the
attribute salary. The verb COST is also added so that
queries of the fonn "Which sales cost more than $1 DO?" are
supported. Finally, the adjectives EXPENSIVE, CHEAP, and
COSTLY are incorporated so the command UList the
cheapest sale is now possible.
This screen provides a method of specifying values for
numeric attributes that can be associated with adjectives
with subjective meanings. This is because words like rich
and poor or young and old can have very different
meanings, depending on the audience or situation. In this
example, RICH is associated with salaries over 70,000
dollars.
The second major classification of attributes is those
attributes that are represented by character data values.
The Define Character Attribute screen, illustrated in Display
e, is used to define such attributes to the Knowledge Base.
B
If the form of compensation selection is made irstead, as
would be the case in this example, then SALARY,
COMPENSATION, PAY, and REMUNERATION are added to
the Knowledge Base as vocabulary associated with salary.
Two verbs, EARN and MAKE, are also included so queries
like "How much did Bob eam?~ are recognized.
There is a third option, Some other kind of money
attribute, for which SAS/ENGLISH software makes no extra
assumptions about this attribute.
As shown above, default adjectives like CHEAP are
provided for a price monetary attribute, but none are given
344
SAS/KHGLISIl, Define Choracter
l\ttr1bute------------~,
Definition ot character variable
in data
.~t
and how they are used until the KBA provides this type
of information. The original creator of the employee data
set did a good job in providing descriptive names for the
various variables in the data set. The variable names
impart meaning and implied use for the data values to a
human but not to a computer program (at least not yet).
Although SASfENGLISH software understands the
concepts associated with numeric and character
attributes outlined above, the system does not make any
inference as to the use of any object or attribute without
explicit instructions from the Knowledge Base
Administrator.
S~;(
PERMDATl\.EHPUU
Noun used to .efer to this attrihute,
Choose the best description of SIX:
o A name associated with EMPLOYEE.
o An ldentifier of EMPLOYEE.
o A value that classifies EKPLOYEE.
" A location associated .. ith EMPLOYEE.
o An identifier ot onother Object uuted to EMPLOYEE.
o Some other property of EMI'LOYEB.
_
_
specify nouns to refer to SEX.
Specify verbs relating SEX to RMPLOY~E.
sp"dfy
_
_
Add dah valuu of SEX to the dictionary.
oehne data value mapping. for SIX.
o"fine class options for SEX.
_
~QnneetioD=
between
nx
_
<Go back>
Display 8
~nd
"MPLOYEE.
For the current character attribute SEX, most people
would draw the logical conclusion that the data values
are likely to be F and M and represent FEMALE and
MALE, respectively. Although this inference is indeed
correct, in this example it need not be always true.
SAS/ENGLISH software uses the ClaSSifier Attribute
screen, shown in Display 9, to define the relationships
between concept or vocabulary and data value.
<lIelp>
SAS/ENGUSH Define Character Attribute Screen
In the middle of the screen there are several general types
of character attributes from which the KBA must choose the
best description of the attribute. As was the case with the
numeric attributes, the selection of the description or type
adds information to the Knowledge Base. The various
character types are the following:
SIISIRNGLlSII: ClauifiH A t t r t b u t e ' - - - - - - - - - - - - - - -
Defiuing classificatien attribute nx
in data $et PlllUlDATA.EIIPLYU
_ Use llatinq scnen
_ lIord denotes data ut object
lIerd:
Value:
Obj
em<! Word
a name
~>
Value
,
'"
This type is chosen if the values of the attribute
are names of the data set object being defined.
These may be names of persons or things; they
may be complete names or parts of names.
~U
KASCULnU;:
FEMALE
I'E)UNINE
,,~
an identifier
This type is chosen if the attribute uniquely
identifies the Object or <;tata set observation.
SAS/ENGLISH software assumes that such an
attribute forms a primary singleton key.
<Other Options>
a value that classifies
This type is chosen if the attribute classifies or
categorizes the object in some manner. The data
values may classify as boolean attributes, or into
many categories. Typical classifiers might be job
titles or gender of employees (as in this
example), or a status label for a project (active,
inactive, completed, and so on).
Display 9
<Goback>
<lIelp>
SAS/ENGUSH Classifier Attribute Screen
On this screen, the vocabulary that can be recognized in
a query is found in the Word column and the data values
that are equated with each word are found in the Value
column. More than one word can be associated with a
particular data value, as multiple data values can be
associated with a particular word. This screen shows
examples of the first type of association.
a location
This type is chosen if the data values for the
attribute represent locations or addresses. This
attribute may be part of a typical address or
some other variety of geographical location.
In the second type of association, one word refers to a
list of possible values if a job attribute exists for an
employee object. The classifier attribute JOB could have
the data values MANAGER, CIVIL, and MECH. The
words manager, civil engineer, and mechanical engineer
could be associated with each value. Furthermore, you
can define engineer as a synonym for someone who is
either a civil or a mechanical engineer.
an identifier of another object
This type is chosen if the values of the attribute
identify some data set object other than the
current object.
some other property
This type is chosen if none of the other types fit
the attribute. SAS/ENGLISH software will make
no assumptions about this type of attribute and
will not add any default information to the
Knowledge Base for it. This type should rarely, if
ever, be chosen.
CONCLUSION
There are other aspects of Knowledge Base definition
that are not covered here. These include how to specify
which attributes are components of composite locations
or names, how to define new attributes that are
mathematically computed from the values of other
attributes, how to collect attributes into a group so they
can be accessed collectively as a single attribute, how to
specify units of measure for numeric quantities, how to
Continuing with the screen example, the obvious choice
for the best description of the attribute SEX is that the
data values for this variable classify employees into one
of two groups, based on gender. An important concept
to understand is that the SAS/ENGLISH product does
not (and cannot) make any assumptions about the data
345
specify more specialized object options, and how to
define additional verbs for use in queries.
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to Expert Systems; Knowledge-Based Systems, New
York: Macmillan.
SAS/ENGlISH software, like any other AI application of
this type, is only as powerful and as useful to users as
the Knowledge Base that defines the application.
Parsaye, K. and Chignell, M. (1988), Expert Systems for
Experts, New York: John Wiley and Sons.
RiCh, E. (1983), Artificial Intelligence, New York:
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DISCLAIMER
SAS/ENGLISH software is an experimental product (the
first distribution of the product requires Release 6.07 of
the SAS System), and the final implementation
appearance of the product may differ from what is
presented in this paper.
Shank, R.C. (1987), "What is AI, Anyway?: AI
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SAS, SAS/ACCESS, SAS/AF, SAS/ASSIST, and
SAS/ENGLISH are registered trademarks or trademarks
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indicates USA registration.
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