CIS4330: Professor KirsArtificial Intelligence Slide 1 An Overview of Artificial Intelligence.

CIS4330: Professor Kirs Artificial Intelligence Slide 1

An Overview of Artificial Intelligence


TOPICSTOPICS AI Background

• How did we get here and Why? Natural Language Processing (NLP)

• How do you deal with Symbolic Representations?

Neural Networks

• How can machines be made to emulate humans?


AI Background

• C. 270 BC: An Greek engineer named Ctesibus made organs and water clocks with movable figures.

• People have always been fascinated with giving machines human Abilities

• 1921: R.U.R. (Rossum's Universal Robots): A Play by Karel Capek

• The Movie Frankenstein (1931)

• “Robot" comes from the Czech word "robota" (forced labor)

• Mary Shelley’s Book Frankenstein (1818)

• Jacques de Vaucanson (1709 -1782) created a mechanical duck that ate and drank with realistic motions of head and throat, produced the sound of quacking, and could pick up cornmeal and swallow, digest, and excrete it.

• Science fiction writer Isaac Asimov first used the word "robotics" to describe the technology of robots and predicted the rise of a powerful robot industry (1941) Robot from the 1921

play "R.U.R."


AI Background

• Turing Test (1950)• Newell and Simon (1954)

• conceived of using computer programming language to build theories of human symbolic behavior

• showed how a wide range of cognitive processes in problem solving and problem understanding can be explained in information-processing terms and modeled with computer programs.

• People have always tried (unsuccessfully) to figure out how the brain works

• McCulloch and Pitts (1943) developed a (workable) mathematical model of brain (networks of neurons) functioning (Binary, Since firing is an ‘all-or-none’ process)• Influenced John von Neumann (1945: Stored Programs)

• Led to the use of Neural Networks (discussed later)• Encouraged the development of Perceptrons (Learning Systems)


AI Background

• Dartmouth Workshop (1956)• Introduction of the term AI• First conference on robotics

• LISP (1958)

• Arthur Samuel’s Checker Program (1955)• First ‘Learning’ Program

• Performed a look-ahead search from each current position

• Saved a description of each board position encountered during play together with its backed-up value determined by the minimax procedure

• “If the program is now faced with a choice of board positions whose scores differ only by the ply number, it will automatically make the most advantageous choice, choosing a low-ply alternative if winning and a high-ply alternative if losing" (Samuel, 1959, p. 80).

• The first programming language dedicated to AI


AI Background

• Shakey the Robot (1970)• The first mobile robot using AI Programming

• MYCIN (1975)• Once MYCIN determines the most likely cause of

infection and accounted for the patient's allergies, it will suggest a course of medication

• Uses rules like, 'If the infection is primary bacteriemia, and the site of the culture is one of the sterile sites, and the suspected portal of entry of the organism is the gastrointestinal tract, then there is suggestive evidence that the identity of the organism is bacteriodes."

• Because Physician’s Distrusted MYCIN, it was the first ES to provide explanations

• Dendral (1965)• First (?) Expert System

• Chemical analysis of organic compounds using mass spectroscopy


• LISP Machines (LISPM) (C. 1980)AI Background

• A computer which has been optimized to run lisp efficiently and provide a good environment for programming in it

• 1985: Over 100 US Companies offered AI Oriented Technologies for sale

• In 1986-87 the demand in AI systems decreased, and the industry lost almost a half of a billion dollars

• 1991: Desert Storm• AI-based technologies were used in missile systems, heads-up-displays,

and other advancements.

?? Why the Change ???• The lack of Application vs. Theory

• AI once again becomes a “Hot Topic”


AI Background?? What are Computers

A ‘Typical’ Computer A ‘Typical’ Human

Better at than Humans ???

• Fast Calculations • Fast Recall• Short-Term Memory (RAM) • Long-Term Memory

• Sequential Processing • Massive Parallelism• Ah ….. Fast Calculations • Fault Tolerance• Ah ….. Fast Calculations • Dealing with Ambiguity

• Ah ….. Fast Calculations • Adapting to Circumstances• Ah ….. Fast Calculations • Creativity• Ah ….. Fast Calculations • Learning• Ah ….. Fast Calculations • Associations• Ah ….. Fast Calculations • Procreating

-- Alright – That’s pushing it!! You Win!! Human’s are Superior to Computers !!


Natural Language Processing (NLP)• Symbolic Manipulation• Uses (Existing and Future):

• Information Retrieval (IR)• Internet/Automated Search Engines/Web-Crawlers• Document Classification

• Word-Processing Assistance (WP “Wizards”)

• Expert Systems• Indexing (Textbook)

• Keyword Classification

• Extensions:

• E-Mail Routing

• Voice Response

• Voice Recognition


• Underlying Problems

Retrieve all articles having the Key Word “E-Commerce”

Articles Retrieved

WSJE-Commerce Stocks Down This Week

~~~~~~~~~~~~~~~~~~~~~~~~

MISQE-Commerce

Strategies~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~

NewsWeekE-Commerce:

Who’s Using it~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~

ElleBuying Clothes at E-Commerce

Sites~~~~~~~~~~~~~~~~~~~~~~~~

CACMDesigning E-Commerce

Webs~~~~~~~~~~~~~~~~~~~~~~~~

Useful Articles Unrelated ArticlesWhere:

Natural Language Processing (NLP)

• Suppose you wish to get general information about E-Commerce

• Document Retrieval Problems


• Document Retrieval Problems• Underlying ProblemsNatural Language Processing (NLP)

• Assume we have There are a total of 50 Documents• Of those, assume only 11 are relevant

• Recall: The Percentage of Relevant articles found

About 3 of 11 (27%) Available Articles RetrievedWhere are we now??



• Assume we have There are a total of 50 Documents• Of those, only 11 are relevant

• Recall: The Percentage of relevant articles found • Precision: The Percentage of Useful articles found

About 3 of 9 (33%) Articles retrieved are relevantWhere are we now??



• “Bag of words” Approach

?? How do Internet Search Engines Retrieve Documents ???

• Count of Simple occurrence frequencies (For listing order)

• No attention paid to inter-word relationships

• No attempt made to characterize documents

• Problems:

• Words are ambiguous

• Words are used in different forms

• Words are used synonymously

?? WHY ??? Can’t the process be improved ???

-- Stay Tuned --



• Document Analysis Problems• Identity Recognition: vs.

~~~~~~~ John Smith ~~~~~~~ Olusegun Obasanjo ~~~~~~~~~~

Over 95% AccuracyWhere are we now??



• Document Analysis Problems• Identity Recognition:• Associations (Identifying co-referential items):

~~~~~~~ John Smith ~~~~~~~ Olusegun Obasanjo ~~~~~~~~~~

~~ Mr. Obasanjo ~~~~~ The President of Nigeria ~~~~~~~~~~~~

Where are we now?? About 85% Accuracy



• Document Analysis Problems• Identity Recognition:• Associations (Identifying co-referential items):• Ambiguous Terminology:

• The bridge of one’s nose

• The bridge of a pair of glasses

• The bridge over a river

• The bridge of a ship

• A dental bridge

• A guitar bridge

• A game of bridge



• Document Analysis Problems• Identity Recognition:• Associations (Identifying co-referential items):• Ambiguous Terminology:

• Need to disambiguate relative to:• Hand-constructed Senses (heuristics)

• English Dictionaries

• Bilingual Dictionaries

• Thesauruses



• Document Analysis Problems• Identity Recognition:• Associations (Identifying co-referential items):• Ambiguous Terminology:• Non-contributory Terminology

• There is a need to parse terms/phrases to reduce searches

• The problem is How to do it

• The Information Systems are used …. → Information System

• The Information Systems → Information System

• Information Systems → Information System




• Some words can readily be eliminated (Stop Words)• a• an

• be• is

• not• or

• the• to

• This can sometimes be problematic:

• was• were

• Search for “IS” (the common initialization for Information Systems)

• Search for the phrase “to be or not to be” (from Hamlet)




• Some words/phrases can readily be eliminated (Stop Words)• Prefix/Infix Removal (Stemming)

• prefix Removal: megavolt volt• infix Removal: un-bloody-likely unlikely

• Still Problematic:

• Isn’t megavolt a relevant search term?

• Does un-bloody-likely need additional parsing?




• Some words/phrases can readily be eliminated (Stop Words)• Prefix/Infix Removal (Stemming)• Suffix Removal (Stemming)

• If a word ends in “ies” but not “eies”, “aies” “y”• Queries Query• Berries Berry

• Hierarchies Hierarchy• Glossaries Glossary

• BUT, what about:• Series Sery ???





• If a word ends in “es” but not “aes”, “ees”, “oes” “e”• Loves Love• Cares Care

• Mandates Mandate• Envelopes Envelope

• BUT, what about:• Cactuses Cactuse ???





• If a word ends in “s” but not “us”, “ss” “” (eliminate)• Wants Want• Walks Walk

• Bananas Banana• Maniacs Maniac

• BUT, what about:• Has Ha ???





• Additional Considerations:• Words ending in “ed”, “ing”, “ational”, “ation”, “able”, “ism”, etc.

• Additional Problems:• Bed B ? Be ?

• Fling Fl ?

• Able “” ? • Prism Pr ?



• Document Analysis Problems• Document Classification Problems

• The goal is to be able to classify any document:

Music

Sports

Business

Mud Slinging

• Although it is too often:

Other




• Simple Classifications (“Bag of Words” - Webcrawlers)

• Documents are scanned for words/phrases

• Lists of most frequently occurring words/phrases are maintained

• Problems:• Massive Lists needed• Very Slow: How many websites and documents at each site are

there? How often are new sites added? How often are documents added to existing sites? How long to determine frequencies?

• Spamming:

SEX SEXY MONICA LEWINSKY JENNIFER LOPEZ CLAUDIA SCHIFFER CINDY CRAWFORD JENNIFER ANISTON GILLIAN ANDERSON MADONNA NIKI TAYLOR SEXY SEXY ELLE MACPHERSON KATE MOSS CAROL ALT TYRA BANKS FREDERIQUE KATHY IRELAND PAM ANDERSON KAREN MULDER VALERIA MAZZA SHALOM HARLOW AMBER VALLETTA LAETITA CASTA SEXY SEXY BETTIE PAGE HEIDI KLUM PATRICIA FORD DAISY FUENTES KELLY BROOK SEX SEXY MONICA LEWINSKY ……..

Looking for an article on Jennifer Aniston??




• Another approach is to analyze the frequency of words/terms for a given document occurring in each category

Music Words• Tempo• Symphony• Volume

•••••

Sports Words• Baseball Game• Points scored• Teams

•••••

Business Words• Profit• Stock Value• Assets

•••••

M-Sling Words• So’s-your-old-man• You Stink• Liar, Liar

•••••

Word Counts• Organization (24)• Profit (16)• Volume (12)

•••••

6 Matches

12 Matches

42 Matches

22 Matches

Business Document

Problem: Establishing Category Lists




?? Is it worth it ???• Research shows it is:

• Hull, D.A. (1996): Stemming algorithms: A case study for detailed evaluation, in Journal of the American Society for Information Science, 47(1): 70-84

• Web Search engines almost never use it

?? WHY ???• Time

• Complexity

• Cost

• Lack of Consistency

• User Expectations

• Foreign Language Usage

(So Far)


????????????? Any Questions

(Please !!!) ?????????????


Date post:	28-Dec-2015
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