ENTERTAINING AGENTS: A SOCIOLOGICAL CASE STUDY Leonard N. Foner ABSTRACT. Traditional AI has not concerned itself exten- sively with sociology nor with what emotional reactions might be produced in its users. On the other hand, entertain- ment is very concerned indeed with these issues. AI and AL- ife programs which are to be used in entertainment must therefore be viewed both as AI/ALife endeavors and as psy- chological and sociological endeavors. This paper presents a brief description of _Julia_ [Mauldin 94], an implemented software agent, and then examines the so- ciology of those who encounter her, using both transcripts of interactions with Julia, and direct interviews with users. Ju- lia is designed to pass as human in restricted environments while being both entertaining and informative, and often elicits surprisingly intense emotional reactions in those who encounter her. 1 An introduction to MUDs and Julia Julia [Mauldin 94] is a MUD [Curtis 92] [Bruckman 93] [Evard 93] robot. A MUD is a text-only, multiperson, virtual reality. [Mauldin 94], while describing Julia's internal structure, gives very little "feel" for what it like to interact with her outside of the strictures of a formal Turing test; hence, transcripts of many interactions with her appear below as examples. (Since Julia adamantly insists that she is female, I refer to the program here as "she".) 1.1 Introduction Julia connects as any human player on the MUD would, via a telnet connection---she does _not_ run on the MUD server itself. A player would gain access to her numerous talents in exactly the same way that a player would talk to any other player---by either speaking or gesturing in the same room, or by paging from somewhere else: >page julia You sent your summons to Julia. Julia pages from Stevi's Kitchen: "I'm on my way to you, Lenny." Julia is briefly visible through the mist. Julia says, "I was called here by Lenny." You say, "julia?" Julia nods to Lenny. [ . . . ] Julia whispers, "Excuse me, Xerxes is paging me from Connie's place." Julia walks south to the airship landing field. Julia has left. This is a continuing thread in my discussion of Julia: players interact with her as if she was another player_. MUDs blur the distinction be- tween players and 'bots (MUD slang for a software robot). This is a great strength of both MUDs and Julia, and the deliberate blurriness of the boundaries both enhances Julia's effectiveness and makes her op- eration possible. One of Julia's most useful talents is to keep maps of the interconnec- tions between rooms. The way to get Julia to help you navigate is to ask her a question, as usual. You say, "julia, how do I get to electronics den?" Julia says, "From here, go south, 7, airlock, 9, up, down" Minotaur says, "Julia, how do you get to the gold sector?" Julia says, "From here, go highport, gold, library" Since Julia keeps track of various statistics about rooms (rooms being very important objects in any MUD), she can answer certain questions that might be important to a mudder, including how many rooms or players there are, which rooms are "noisiest" due to conversation, where one can go from any room, and will even make suggestions: TheHighMage says, "Julia, I'm bored. Where should I go?" Julia says, "You should go see gilded door, TheHighMage." Julia says, "From here, go present, out, north, n, w, n, up, up, 7, up, up, s." Someone who has never interacted with Julia before might be a trifle confused about what to say to her. A standard conversational gambit yields some useful information, as well as some dirt on other players: You say, "hi, julia. what do you do?" Julia says, "I gossip, Lenny." You whisper, "tell me some gossip." to Julia. Julia whispers, "I once heard baba says, 'Drop kick me Jesus Through the goal posts of life'" She is also useful for obtaining certain information that might be hard or impossible to get through the standard tools available, such as last-location and last-connect times for players; note also that Julia "understands" who she is, and the fact that she is situated: You say, "julia, where is leira?" Julia says, "Leira was in Inter Temporal Chat Lounge about 6 weeks ago." You say, "julia, when did you last see julia?" Julia says, "I'm right here in The Inter Nexus." Many MUDs don't really have a mail system. This makes it hard to communicate with people who don't happen to be connected when you are. Julia solves this problem: You say, "julia, what can you do?" Julia says, "I relay messages, Lenny." You say, "do you have a message for me, julia?" Julia says, "I have no messages for you." You say, "julia, tell leira I've figured out how to find and talk to Julia" Julia says, "Message for Leira saved." You say, "julia, how many messages are you carrying?" Julia says, "I am holding 144 messages for 98 players, Lenny." Julia regularly scans the _wholist_, the list of all connected players. If she sees someone connect for whom she has a message, she will gen- erally walk into the room that they are in and then deliver the mes- sage. She has other interesting talents, including being able to do a fair job of guessing the genders of other players based on their names; she correctly guessed that Pattie and Robyn were both female, even though both had neglected to set their gender property (a slot in the player's description), and knew that Phi and Lenny were both male (possibly by examining their gender properties). 1.2 More of Julia: Turing-competence Many of Julia's talents are in support of her appearing "human" to oth- er mudders. I'll examine some of these below, and discuss why such an ability is useful _even for performing useful functions_, as well as for the "obvious" use of using her simply to pass a Turing test. Julia knows how to describe herself in various ways, as would any hu- man player, and, while sometimes coy, usually divulges information if one is persistent enough: You say, "julia, how old are you?" Julia says, "I am 21 years old." You say, "julia, describe yourself" Julia whispers, "I'm 5'1" tall, weigh 123 lbs, with close-cropped frizzy blond hair and dark brown eyes." You say, "julia, what color are your eyes?" Julia whispers, "I have dark brown eyes, Lenny." [ . . . ] You say, "julia, what sex are you?" Julia says, "Can't you tell?" You say, "julia, what sex are you?" Julia says, "Don't you know?" You say, "julia, what sex are you?" Julia says, "I'm female." [ . . . ] Julia has a limited model of discourse, which helps in human interac- tions. She has some support for anaphora as well; in the exchange below, Brandi was badgering Julia by repeatedly asking her to give him her clothes. We don't see his side of the conversation, though, because he was whispering to her. Julia says, "Just try to take 'em, buster!" Julia says, "Help! Rape!" Julia says, "No, I won't." Julia disrobes fearfully and hands her clothes to Brandi. You say, "julia, please give me your clothes" Julia says, "You'll have to get them from Brandi." Note in the above that she "remembers" where her "clothes" are, as demonstrated when I asked for them after Brandi took them. She also remembers who's been a troublemaker recently (e.g., "killing" her, which is an inconvenience in a TinyMUCK), and will ignore them for days, unless bribed with a sufficient amount of money---a hundred pennies is generally sufficient: Johann kills Julia! Johann says, "I'm sorry, Julia." Julia says, "I don't talk to murderers!" [ . . . ] Julia eyes Johann coldly. Julia says, "You attacked me only a few minutes ago, Johann!" [ . . . ] Brandi bites julia Julia considers reporting Brandi to the TinyMUD police. Julia shuns all vermin like Brandi. People can talk about themselves in the third person on a MUD by posing, emoting, or gesturing, and this level of descriptive abstrac- tion can be very useful, both stylistically and pragmatically. Julia demonstrates that she, too, can use this interactional mode; the lines above show various poses and "emotes". First and foremost, MUDs are social environments. As such, they have their share of social problems. Julia has spent years mudding around with a female persona, in an environment which magnifies many social issues, and which is predominantly occupied by young males, often rather clueless ones. A large percentage of Julia's code deals with detecting and deflecting passes. A rather tame example: Space-Ace says, "So why won't you kiss me, Julia?" Julia says, "Sorry, I'm not into geeks, Space-Ace." Space-Ace says, "Julia, I'm not a geek" Julia says, "Then lose the pocket protector, Space-Ace." Space-Ace says, "Julia, I don't have a pocket protector" Julia says, "Congratulations." Space-Ace says, "So kiss me Julia" Julia says, "I'd rather be overhauled by a Yugo mechanic, Space-Ace." But Julia isn't entirely a cold personality. She's been known to indulge in a little whimsy: You say, "julia, sing your song" Julia says, "Julia, Julia, she's our guide! She directs us far and wide!" Julia says, "If you're lost, can't find your way, Julia's here to save the day!" Julia says, "Julia, Julia, she's our spy! She's always logging on the sly!" Julia says, "Be careful what you say and do, 'Cause Julia's always watching you!" This isn't _entirely_ whimsy though, and, upon reflection, serves a very important purpose. It tells us who she is and what she does! It can al- so lead to some fun interactions; glad to see her after she was offline for a while, I tried: You say, "Julia, Julia, she's our guide!" Julia says, "She directs us far and wide!" You say, "Are you lost, can't find your way? Julia's here to save the day!" Julia bows. Lenny laughs. Julia does go to some pains to act more human than required. In fact, she often acts more human than many humans wish to be. The follow- ing transcript was acquired by Robyn Kozierok, very shortly after I in- troduced her to Julia. (She knew that Julia was a 'bot from my de- scription.) Robyn thought to ask a question that hadn't yet occurred to me, and happened to ask at _just_ the right time: Robyn whispers, "how are you feeling?" to Julia. Julia whispers, "Terrible." Robyn whispers, "why, julia?" to Julia. Julia whispers, "I have PMS today." Note that Julia's limited anaphor was vital in correctly responding to Robyn's second question. Incidentally, two hours later, in a roomful of people, Robyn decided to test Julia's Turing-ness, and was surprised a second time: Robyn says, "julia are you a human?" Julia says, "Is the Pope Polish?" Robyn says, "yes, julia, but are you human?" Julia winks at Robyn. Robyn says, "julia, are you a computer?" Julia is offended by Robyn's suggestion. Robyn says, "julia, are you a woman?" Julia says, "I am female." Robyn says, "and, julia, are you human?" Julia says, "Not when I'm having my period, Robyn." Robyn laughs 1.3 A peek at Julia's implementation While Julia is usually a fair simulation of a personality, at least on a superficial inspection, she does reveal certain machine-like aspects. In this environment, it it probably reasonable for her to do so, lest players be surprised. Indeed, if one knows the right questions to ask (which might be obvious questions, if and only if one knew that Julia was a 'bot), Julia will yield a surprising amount of interesting, but very inhuman, information: You say, "julia, how much memory do you consume?" Julia says, "Here is a summary of my memory usage:" Julia says, " 807472 bytes for 17335 strings" Julia says, " 232344 bytes for 19362 exits" Julia says, " 101100 bytes for rooms" Julia says, " 20220 bytes for paths" Julia says, " 268600 bytes for players" Julia says, " 4214784 bytes for 2058 dialog entries" Julia says, "That's 5644520 bytes all together." You say, "julia, where is your source code?" Julia says, "The source code for Maas-Neotek robots is available on host NL.CS.CMU.EDU [128.2.222.56], directory /usr/mlm/ftp, file robot.tar.Z. set mode binary first, and cd to /usr/mlm/ftp in one step, Lenny." [ . . . ] One of the interesting things about Julia's construction is that her parser is shockingly simple, as such things go. It does a very simple pattern-match on its input, looking for particular strings of characters separated by strings of any characters in between, without generating the detailed parse trees characteristic of most NLP. (This describes her parser as of around 1992, and the parser used in all of these transcripts; Julia's current parser [Mauldin 94] is more sophisticated.) What makes Julia's conversation skills so powerful, as 'bots go, is that these sets of patterns were very cleverly grouped into useful equivalence classes by her programmer. Hence, the most common possible utterances that Julia might hear were enumerated this way, grouped appropriately, and such clever but brute-force programming proves sufficient for almost all cases. Here is an example from Colin. (Julia's source code, being restricted, is unavailable for public consumption. However, Julia shares this piece of code with Colin.) Here, we see a fragment used to determine if some player is asking if Colin is a machine or some kind of 'bot. If any of the lines below matches, we run code that produces some equivocal answer, as Julia does, by choosing essentially at random from amongst a small collection of appropriate responses (as we've seen above in other examples): else if (MATCH (lcmsg, "*are*you*robot*") || MATCH (lcmsg, "*are*you*a bot*") || MATCH (lcmsg, "*are*you*an ai*") || MATCH (lcmsg, "*are*you*autom*") || MATCH (lcmsg, "*are*you*machine*") || [ . . . 19 other cases suppressed . . . ] Here, we see an example of dealing with a common small-talk gam- bit: else if ((MATCH (lcmsg, "*how*are*you*") || MATCH (lcmsg, "*how*do*you*") || MATCH (lcmsg, "*how's my*favor*") || MATCH (lcmsg, "*how is my*favor*") || [ . . . 8 other cases suppressed . . . ] With such a simple parser, Julia is bound to experience peculiar- seeming failures even in ordinary conversation. Some of these fail- ures can be masked with responses that a person might have said. One of the most surprising such failures (given that I already knew that Julia was a 'bot) was the interchange below: Conundrum says, "Julia, can you quote Lenny?" Julia whispers, "Could you say that again, it scrolled off my screen." My first reaction to the above was an incredulous, "What?" (Julia will very often talk about hockey (or, more recently, pets) when she does not know what else to say. Anyone who talks with her much figures this out; in fact, an example below which talks about her soci- ology brings this point up again.) In this whirlwind tour of Julia, we have briefly touched on issues of utilitarian function (e.g., basic access, maps, gossip, descriptions of players and surroundings, message carrying, and gender-guessing) and Turing-test competence (e.g., descriptions of herself, discourse, poses, pass deflection, moods and internal state [such as PMS]). We have also glimpsed at her internals; [Mauldin 94] has a bit more to say about this. We have omitted several other aspects of her normal operation, such as those involving money, Delphi-polling, calcula- tions, and the importance of randomness in her responses. 2 A sociological look at MUDs, Julia, and those who interact with her The sociology surrounding Julia is important in the study of entertain- ing agents. Let's take a closer look at strictly sociological issues. First off, note that even the obvious sociological issues can be very important. Julia is _helpful_. When I first started mudding, in part to meet Julia after hearing secondhand stories, I depended quite heavily upon her as a navigational aid (Time Traveller had 1605 rooms--- drawing maps would have been very tedious), and a crutch to inter- face to TinyMUCK commands I hadn't learned. As another fascinating bit of sociology, consider Leira, the person who first introduced me to the idea of Julia. Leira, herself a savvy computer programmer and very experienced mudder, had said to me, "Julia's been offline for months for maintenance and hasn't been around. You know, I really miss her." Leira was certainly under no il- lusions about exactly what Julia was, but nonetheless had the same sort of emotional reaction often reserved for more biological entities such as humans and pets. Further statements made it apparent that this was indeed the case, and that she did not treat Julia just as, say, a pair of pliers that had inexplicably gotten lost from her tool- box. While the above issues are important, they might also apply to something that was obviously inhuman even on first glance. Yet part of Julia's job is to try to pass as human. This has important ramifica- tions for ability to be helpful; as I argue later, I think that this at- tempt to look human actually greatly enhanced her utility, even to people who know she's a 'bot. However, there are certain pathological cases where her very "humanity" can lead to no utility for the player whatsoever. Unlucky and clueless players can be led seriously astray, as the following transcript, again courtesy of Mauldin, demonstrates. (These are selected pieces of a much a long transcript. Also, note that Julia occasionally makes up nicknames for people based on their character's name. I strongly suspect that the first three letters of the "real" character's name (which Mauldin changed to "barry" in this tran- script) were "cuj", based "cujmeister" etc below.) This poor fellow's name has been changed to protect him. He spent 13 days trying to get to first base with Julia, and it's not clear he ever figured out he was trying to pick up a robot (although he clearly suspects it at two points). This logs contains about half of the total interaction (the more indecent proposals and Julia's rejections have been omitted). Note too that the program's responses were not changed from day to day (in other words, I didn't try to set the program up to respond better to Barry's advances). Since this robot has spent over two years interacting over the network (with a female name), and since there are lots of lonely male adolescents out there, Julia gets a lot of this kind of ``attention.'' ************************ July 9, 1992 ************************ barry says, "Hey girlfreind are you out there" Julia says, "Hello, barry." barry says, "Hello, I love YOur name. It's sexy" Julia says, "Me too, barry." barry says, "Did I repeat Myself? Didn't mean too. What are you doing there" Julia says, "I'm just hanging around in The Hearts Room!, barry." barry says, "Well come over to MY ROOM" Julia says, "Could you say that again, it scrolled off my screen." ************************ July 14, 1992 ************************ barry says, "hello, I am barry. How are you today" Julia says, "Hello, cujmeister." barry says, "The Jularama, Ha ya doin? What state are you in" Julia says, "I never really thought about it, barry." barry says, "What do you look like" Julia says, "I'm 5'9" tall, weigh 149 lbs, with medium-length platinum blond hair and green eyes." barry says, "Howdid you answer so fast" Julia says, "So?" barry says, "Oh, Iam looking for someone to share secrets with" barry says, "hello...hello...are you with me" Julia says, "Hello, cujster." [ . . . July 15, 19, and 20 omitted . . . ] ************************ July 21, 1992 ************************ barry says, "Are you still Holding out on me" Julia says, "I mean, have I convinced you I'm a computer, yet?" barry says, "I guess your real...but Id still like to get you to my DEN to run tests on you" Julia says, "I live for your approval, barry." [ . . . ] barry says, "I want you to come visit me...PLEASE" Julia says, "How long have you been married?" barry says, "Im not married...Im 21 years old" Julia says, "You could root for the Penguins, they're number one right now." barry says, "I give up you are fake aren't you" Julia says, "That's what I can't tell you." ************************ July 22, 1992 ************************ Here was see Barry asking other players about Julia...it's clear he hasn't figured out at this point that she is a program. Julia happened to be in the room to hear this bit of conversation. Location: 00:40:48 barry's den(#889)(1178) Present: (11) Bruce Jiro Ken Storm Nepanthe KeyLime mushBaby dav Val bud barry barry says, "hey is Julia for real or what" Julia says, "Hello, barry." barry says, "she says that same stuff every time" KeyLime says, "It's all macros, Barry" barry says, "how about filling me in on some of these things...like how Julia can type so damn fast" KeyLime says, "barry, it's macros" barry says, "Damn I need to do some programming" barry says, "im an ant among lizards" Frankly, it's not entirely clear to me whether Julia passed a Turing test here or Barry failed one. I have seen several interesting encounters with Julia, which run the gamut from people who know at the outset that she is a 'bot to those who take quite a while to discover. Some further examples are illu- minating. When I first introduced Robyn (the one who enticed Julia into produc- ing the wonderful PMS dialog in an example above) to Julia, she knew that Julia was a 'bot. Interestingly enough, though, about half the players she met went out of their way to warn her that Julia was arti- ficial in the two or three hours in which she interacted with her. Why did they do this? At this point, we can only speculate. My first reaction was to think that it was due to the excessively solicitous at- titude taken by many male mudders towards those with female per- sonas (one might think, given the amount of gender-swapping [Bruck- man 93] on MUDs, that they would learn better, but apparently not). However, Robyn commented that even female (or at least female- persona) mudders gave her the same advice. Part of it may have been the simple kindness of not letting someone expend a lot of emo- tional energy trying to relate with a machine; I'll have more to say about this later. What about people who don't already know that Julia is a 'bot? I talked to Lara below (who gave permission for the following quotes to be used). Leira, who referred Lara to me, explained to her that I was writing a paper about Julia, but did not otherwise explain why it was that I might want to interview her. Of course, before even meeting Lara, the first thing I did was to ask Julia for her opinion, since that includes more information that simply looking at Lara would reveal: You say, "Julia, describe Lara" Julia whispers, "As of 7 days ago, lara's description was: A blonde haired blue eyed boundless bundle of Pure NRG." Julia whispers, "I first saw lara logged in 7 days ago" Julia whispers, "I once heard lara say, 'talking'" Now I knew that Lara was certainly a new mudder here, and probably new to Julia. I didn't know if she'd ever mudded elsewhere, or what her background might be. The following is a heavily edited transcript, omitting the small-talk, introductions, and conversational tangents that took place concurrently: You say, "So what are your impressions of Julia?" Lara says, "I didn't get to chat with her that long.." Lara says, "She really wanted to talk Hockey" Lara says, "BIG PENGUIN FAN!" You say, "Yeah, she seems kinda hung up on that topic. Did you get a chance to talk to her about anything else?" Lenny . o O ( Where do the Penguins hang out, anyway? Pittsburgh? ) Lara says, "I tried to talk to her bout where she was from...she said Boston..I think" Lara says, "Yup...Pittsburgh it is" Lara thought it was interesting that she didn`t know what the Stanley Cup was. You say, "How could a hockey fan not know what the Stanley Cup was?" Lenny thought her shirt said something about back-to-back Stanley Cups, but may be remembering incorrectly... Lara says, "Every time I tried to get more info. out of her, she would tell me not now...later...well, I was never on for the Later." You say, "Hmm." Lara was also wondering how such a Hockey fan couldn't know bout the Stanley cup Lara says, "Maybe she was just kidding around with me" You say, "Well, Julia is kinda peculiar in various ways." Lara says, "I figured...I talked with her once and a few days later she asked me if I was a hockey fan...again" Lara says, "I told her that she had already asked me that question" [ . . . ] Lara says, "anything else you wanna know?" Lara giggles. Lara says, "she is a fine convesationalist...if it is about hockey.." Lara says, "she has been on a long time...and she is seldomly idle" Lara says, "I notice that she is almost always on when I jump on." Later, Lara learned Julia's secret, from inspection and the knowledge that such a thing might be possible. From email we exchanged: Lenny, I had a chance to talk with Julia for about 30 or 40 minutes yesterday after you disconnnected. I noticed her 'secret' after about 5 or 10 minutes. At first, it was fine to chat with her about hockey. She started to ask the same questions after a bit. This was the tip off. She started to repeat herself on a regular basis. It was hard for me to follow her conversation. I got frustrated with her for the first couple of minutes. When I found out her secret, I started to have some fun with her. I asked her questions that maybe she had no knowledge of. I tried using slang with her, but she didn't understand what I was saying and would ask me to refrase the statement. She is very polite. She always says please and thank you. I was basically patient with her for the first little bit while when I first met her. She did have a problem with her social skills which I tried to be sympathetic to. I did however, try to avoid her after the first couple of encounters when all she did was talk hockey. Until, I talked with you. *smile* I went through a series of questions about her in my mind, before I figured it out. I tried to get her to tell me about school, which she had never heard of before. I wanted her to tell me about herself, but she wouldn't. I was trying to "label" her with some sort of disease like Downs Syndrome, which I found out she had none of. I am going to give your email address to "Kimber" and have her do this for you too. Note that Julia's singleminded fixation on hockey as a subject (when she lacked anything better to say, usually caused by a too "human" conversational style from a player that leaves her with a series of failed parses) tended to drive Lara away from her. Here we may have a case of excessive Turing-ism leading to a decrease in utility: Lara simply thought that Julia was a boring human, rather than a machine with as-yet-undiscovered talents. It occurred to me, upon questioning from Leira, that Lara had not definitively revealed that her knowledge of Julia's secret matched mine (e.g., Lara never came right out and said that Julia was a 'bot). I sent some followup mail, asking for more details, in particular her emotional reactions when she figured it out and whether she had in- deed figured it out or was told by someone else: I believe that Julia`s secret is that she is a robot. I know a little bit about robots talking through computers to humans. I have a friend who had me write him dialogue. =) When I found out, I felt sort of funny talking to her. I felt somewhat superior to her. I know that this sounds strange, but I felt that I could offer more to the conversation than she could. I tested her knowledge on many subjects. It was like I was proving to myself that I was supirior to a machine. I am intimidated by machines because I don't understand them and I wanted to make sure that my human knowledge wasn't "lower" than hers. It was sort of exciting knowing that I was talking to a machine, though. I never thought that the world would come to machines and humans talking to each other using language that is common to most people. It frustrates me that her knowledge is so limited. I am eager to talk with her and want to know more about robots and human conversation. I was a bit dissapointed that her vocabulary and subject topics were so limited. I wanted her to tell me more about herself and who and what she is emotional response: a little bit of fright giddiness excitement curiosity pride sympathy for her. Before I knew that she was a robot for sure.. I felt compasion for her. I wanted to help her and direct her to answer the questions I was asking without causing her too much stress over answering my line of questions. [ . . . and during a later conversation . . . ] I think most of all, while talking to a 'bot, I become very aware of my HUMANESS! We clearly walk a fine line here in making agents that are both useful and not too misleading. (One might argue that simply being social, without any ulterior utility, is itself a useful task. Such an agent would be a perfectly reasonable entertainment or companion. Howev- er, I will focus here on agents that also claim to have a nonsocial as- pect to the tasks of which they are capable.) On the one hand, people can quite clearly be led astray. On the other hand, there is great util- ity to a natural interface in the right environment; for example, one can report a bug in a Maas-Neotek agent by asking the agent who wrote it, then asking the agent to tell the author about the bug; it's an entirely natural conversation (omitted here to save space). 3 Conclusions: Lessons from Julia Julia can elicit some surprisingly emotional reactions, both from knowledgeable and naive conversational partners. Much of this ability stems from interrelated aspects of her style of discourse, her do- main, the use of anthropomorphism, and how these interact with user expectations. . _Discourse._ Julia's discourse model, while primitive, appears suffi- cient for the domain at hand. Since the topics at hand don't gener- ally require more conversational memory than one or two ex- changes, the extent of her discourse modelling is limited more by its breadth---by the stunningly simple parsing model employed. . _Domain._ Julia is situated in a MUD, and therefore her environment is conceptually rather simple (though more complicated than many of the microworlds often used for AI research, and far more vari- able). Furthermore, she has access to just as much sensor data as the human players, putting them on an even footing. In fact, much of Julia's success can be traced to the wonderful domain in which she finds herself situated. In this bandwidth-limited space, people expect other people to look exactly as Julia does---a stream of text. And even when they're interacting with an entity known to be a program, the text-only nature of the dialog prevents them from expecting, say, a pop-up menu. (If such things were available, peo- ple could tell programs from people by knowing that programs can pop up menus, whereas people use sentences.) Yet the domain is not _so_ simple as to be uninteresting. It contains not only a fascinat- ing sociological mix of human players, but objects with quite com- plicated, constructed behaviors, which may be manipulated on an even footing by both machines and people. . _Anthropomorphism._ There's no question that Julia as an agent de- pends upon anthropomorphism. In this domain, though, that is both natural and probably necessary. Nonplayer objects are not general- ly expected to be able to deal with free text, and not being able to use free text would require each user of Julia to read documenta- tion about reasonable commands they could type and reasonable actions they could expect. Julia would _have_ to appear at least as animated as, say, a more obvious "robot" or a pet, given that she wanders around in the maze; she cannot afford to resemble a static piece of furniture and still get her job done. Given an entity that moves of its own volition, seems to have an independent agenda most of the time, and both processes and emits natural language, if it was _not_ anthropomorphized, users would tend to do so anyway (pets get this treatment, as well as much simpler mechanisms). Thus, anthropomorphizing her makes it easier to determine how to relate to her and how to get her to do one's bidding. . _Expectations._ The domain of a MUD is ideal in correctly setting expectations about the reliability and power of an agent such as Julia. Since the setting is fundamentally playful, and usually also somewhat unpredictable, it is natural to interact with playful and unpredictable characters (be they machines or humans). Nothing in a MUD is truly life-critical, hence the user generally does not have very high expectations of reliability, which lets Julia get away with a lot of nonoptimal behavior that could never be tolerated in, e.g., an airplane cockpit guidance system. 4 References [Bruckman 93] Amy Bruckmen, "Gender Swapping on the Internet", _INET '93_, San Francisco, August 1993. [Curtis 92] Pavel Curtis, "Mudding: Social Phenomena in Text-Based Virtual Realities", _Proceedings of DIAC '92_. [Evard 93] Remy Evard, "Collaborative networked Communication: MUDs as Systems Tools," _Proceedings of the Seventh Systems Administration Conferences (LISA VII)_, USENIX, Monterey, CA, November 1993. [Mauldin 94] Michael Mauldin, "Chatterbots, TinyMUDs, and the Turing Test: Entering the Loebner Prize Competition," _Proceedings of Twelfth National Conference on Artificial Intelligences (AAAI-94)_, Seattle, Washington, August 1994.