Chatbots: On Demand Creation of Conversational Agents Engenharia Inform´atica e de ...

103 Pages·2015·1.49 MB·English

Chatbots: On Demand Creation of Conversational Agents
Lu´ıs Filipe Amaral Pinhanc¸os dos Santos
Thesis to obtain the Master of Science Degree in
Engenharia Informa´tica e de Computadores
Supervisor: Prof. Maria Lu´ısa Torres Ribeiro Marques da Silva Coheur
Examination Committee
Chairperson: Prof. Ma´rio Jorge Costa Gaspar da Silva
Supervisor: Prof. Maria Lu´ısa Torres Ribeiro Marques da Silva Coheur
Members of the Committee: Prof. Joa˜o Miguel de Sousa de Assis Dias
October 2015

Acknowledgments
Thereisnoeasywaytostarttoacknowledgeallthepeoplethatsupportedmethroughthelongyears
thatthiscoursetook. Manycameandwentbuttheoldestcoreismyfamily.
I would like to first mention the person that supported me by giving me space enough to grow up
by myself. Through lows and highs my mother was an always present and calm presence through any
adversitiesImayhadencountered.
To my father, who always encouraged me to pursuit what I like, insisting that is never too late to
change. Achangeofcoursewasnotnecessary,Ijustneededtoputmyfootonthegas.
To my brother, who gave me advice through it all. The fault is mine that I only started listening later
inlife,butbetterlatethannever.
To Professora Lu´ısa Coheur, I know I can be a pain in the neck with my relaxed mood but it was a
niceridedespitetheslowmotionspeedofprogression.
To my friend, the ones that are side by side with me in all good and bad moments. I feel lucky to
haveyouallinmylifetorelaxandkeepmyheadclearofmostworries.
And saving the best for last, my best friend. My companion. My safe port. Could not have done it
withoutyou,inallhonesty. YoupushedmehardwhenIwasstartingtoslowdownandkeptshowingme
theway. Wehavebeenlaughingandlovingthroughthepast8yearsbutIwantmanymore. Thankyou,
Ca´tia.

Abstract
The Instituto Superior Te´cnico’s Spoken Language Systems Laboratory (L2F) group has a variety
of dialogue systems that would be best explored if fit together in a single software engineering project.
Thisnewprojectshouldbethefoundationofasystemthatcreatesaconversationalagentondemand,
unifyingseveralL2Ftools.
Previous to any architecture definition or implementation, a study of the system was required. We
neededtoidentifycontrolpoints,understandthestructureandhaveaglobalvisionofhoweachsystem
works. Wealsowantedtoobservesomesystemsonthemarket,tryingtoacquireknow-howastowhat
todoinourownsystem.
A first approach to a possible architecture was designed, trying to find a solution that would meet
our demands in terms of modularity, customization and integration. Afterwards, we started the imple-
mentation process and went over an iterative process of the architecture until we reached our current
state.
Tenuserconfigurationscenariosweredefined,tryingtounderstandthelevelofchangesnecessary
tosatisfyeachspecificationandevaluatetheflexibilityofoursystem. Wealsodiduserevaluationonthe
system,asthisisasystemdesignedforendusersandnotonlyforprogrammersoftheL2Fgroup.
Keywords
ConversationalAgent;Chatbot;DialogueSystem;
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Resumo
O Laborato´rio de Sistemas de L´ıngua Falada (L2F) do Instituto Superior Te´cnico tem uma grande
variedade de sistemas de dia´logo que seriam melhor exploradas se encaixadas num u´nico projecto.
Este novo projecto devera´ ser a base de um sistema que cria um agente conversacional on demand,
unificandodiferentessistemasdoL2F.
Antes de qualquer definic¸a˜o ou implementac¸a˜o de uma arquitectura, e´ necessa´rio um estudo ao
sistema. Precisamos de identificar pontos de controlo, perceber a estrutura e ter uma visa˜o global de
comocadasistemafunciona. Tambe´mquisemosobservaralgunsdossistemasexistentesnomercado,
tentandoadquiriroconhecimentodoquefazernonossosistema.
Numaprimeiraabordagem,desenha´mosumaposs´ıvelarquitectura,tentandochegaraumasoluc¸a˜o
que iria de encontro aos nossos requisitos em termos de modularidade, customizac¸a˜o e integrac¸a˜o.
Depois,comec¸a´mosoprocessodeimplementac¸a˜oepassa´mosporumprocessodeiterac¸a˜onaarqui-
tecturaate´ chegarmosaopresenteestado.
Definimos dez cena´rios de configurabilidade, tentando perceber o n´ıvel de alterac¸o˜es necessa´rias
para satisfazer cada especificac¸a˜o e avaliar a flexibilidade do nosso sistema. Realiza´mos ainda uma
avaliac¸a˜ocomutilizadores, vistoqueestesistemafoidesenhadoparautilizadoresfinaisena˜oapenas
paracolaboradoresdogrupoL2F.
Palavras Chave
AgenteConversacional;Chatbot;SistemadeDia´logo;
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Contents
1 Introduction 1
1.1 Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 DocumentOrganization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2 Background 5
2.1 Edgar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.1.1 ProgramD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2 SaySomethingSmart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2.1 HowdoesSSSwork? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2.2 TheSSSmeasures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.2.2.A Frequency(M1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.2.2.B AnswerSimilaritytotheUserInput(M2). . . . . . . . . . . . . . . . . . . 11
2.2.2.C QuestionSimilaritytotheUserInput(M3) . . . . . . . . . . . . . . . . . . 12
2.2.2.D TimeDifference(M4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2.2.3 OtherConfigurationoptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2.3 Talkpedia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.4 TalKit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.5 JustChat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2.5.1 WhatcanbegivenasaninputtoJustChat? . . . . . . . . . . . . . . . . . . . . . . 16
2.5.2 WhatistheexpectedoutputinJustChat? . . . . . . . . . . . . . . . . . . . . . . . 18
2.5.3 ButhowcanIchoosethekindofoutputsthatIwant? . . . . . . . . . . . . . . . . 19
2.5.4 WhatcanIdowiththeJustChatFilters? . . . . . . . . . . . . . . . . . . . . . . . . 21
2.5.4.A DomainFilter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2.5.4.B PersonalFilter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
2.5.4.C BlackListFilter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
2.6 JustAsk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
3 RelatedWork 27
3.1 PandoraBots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
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3.1.1 BasicPandoraBot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.2 VirtualHumanToolkit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
3.2.1 Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
3.2.2 NPCEditor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
3.2.2.A Utterances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
3.2.2.B Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
3.2.2.C Classifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
3.2.2.D People . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
3.2.2.E Conversations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
3.2.2.F Chat. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.3 OtherRelatedWork . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.3.1 DialogSystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
3.3.1.A OpenDial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
3.3.1.B TRIPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
3.3.1.C OlympusandRavenclaw . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
3.3.2 DataIntegration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
4 Architecture 45
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
4.2 ProposedArchitecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
4.2.1 PresentationLayer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
4.2.2 ServiceLayer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
4.2.3 BusinessLogicLayer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
4.2.4 DomainLayer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
4.3 ImplementedArchitecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
5 Implementation 53
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
5.2 Plugins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
5.3 AnswerRetrievalAlgorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
5.4 Towardsaflexibleconfiguration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
5.4.1 TheBrain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
5.4.2 Plugins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
5.4.3 Language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
5.4.4 OtherSystemsConfigurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
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