dmark@acsu.buffalo.edu (David Mark) (10/21/90)
Has the "Virtual Reality" (VR) community addressed the issue of when something might be "too real"? I have bought into the philosophy that a computer information system is primarily intended to allow the user to interact vicariously with real or possible worlds. The computer, the software, the interface, should be as unobtrusive as possible. The user should be thinking about phenomena or problems of the real world. It then occurred to me that this seems to imply that VR is the way to go. (And VR obviously is important despite what I am about to 'say'.) So, here goes: An aerial photograph is more "realistic" than a map. If we pushed display of vertical views of a city toward greater and greater "reality", then the displays would look more and more like colored airphotos. But it is widely believed that a road map is better for finding one's way around in a city than would be an airphoto, even and airphoto with street names overlain. The utility of the road map in such situations stems from the fact that it is a *selective* representation of reality. Roads are emphasized, and most other features are suppressed. In fact, it may be claimed that this selection, symbolization, and simplification is the essence of cartography. So to rephrase my original question, has the Virtual Reality community addressed the issue of how real the presentation should be, and when the presentation to the user should be simplified and selective? David Mark National Center for Geographic Information and Analysis dmark@acsu.buffalo.edu
kevino@fs0.ee.ubc.ca (kevin o'donnell) (10/21/90)
In article <9638@milton.u.washington.edu>, dmark@acsu.buffalo.edu (David Mark) w rites: > An aerial photograph is more "realistic" than a map. If we pushed > display of vertical views of a city toward greater and greater "reality", > then the displays would look more and more like colored airphotos. But > it is widely believed that a road map is better for finding one's way around > in a city than would be an airphoto, even and airphoto with street names > overlain. The utility of the road map in such situations stems from the > fact that it is a *selective* representation of reality. Roads are emphasized , > and most other features are suppressed. In fact, it may be claimed that > this selection, symbolization, and simplification is the essence of > cartography. > > So to rephrase my original question, has the Virtual Reality community > addressed the issue of how real the presentation should be, and when the > presentation to the user should be simplified and selective? > The idea is to make the presentation variable depending on the data and on the use the user wants to put it to. As you suggest, both the above formats could be usefull in different situations. The amount of (real world) realism would depend on whether it was needed. I would guess that initially, it would be up to the user to indicate, in some fashion, what data he wants to look at, what attributes are of interest and in what manner they should be displayed. An intelligent set of defaults will obviously be important. Some sort of built in AI to intuit what we are hunting for and modify the defaults would be great. Lately, people have been mostly discussing intuitive navigation in VR. What are peoples ideas on intuitive manipulation of VR? How best should the user modify the manner in which the world is displayed and the data presented? Kevin ------------------------------------------------------------------------ |"Yes," said Piglet, "Rabbit has Brain." | Kevin O'Donnell | |There was a long silence. | kevino@ee.ubc.ca | |"I suppose," said Pooh, "that`s why he never | U of British Columbia | | understands anything." | Vancouver, Canada | ------------------------------------------------------------------------
kirlik@chmsr.gatech.edu (Alex Kirlik) (10/21/90)
In article <9638@milton.u.washington.edu> dmark@acsu.buffalo.edu (David Mark) wr ites: > some things deleted > >So to rephrase my original question, has the Virtual Reality community >addressed the issue of how real the presentation should be, and when the >presentation to the user should be simplified and selective? > I am happy to see someone raise this issue. I think it's important. No, I don't believe they have. While I am pleased to see advances in VR along the lines of realism, I have often wondered what is really driving this work. One thing that's absolutely amazing about perception is how little realism you really need to "see" something; like the Grand Canyon on a little piece of cardboard while sitting in your living room. I know this is missing the point of the original posting, which seemed to be that abstraction (rather than pure realism) is sometimes better for certain tasks. I agree here too. It strikes me that VR is predicated on achieving the phenomenological aspects of perception, the quality of "presence," which may in fact be a very noble and interesting task. Yet, nowhere have I ever found any empirical evidence to suggest that the phenomenonological side of perception is integral to the cognitive side, i.e., to selecting the appropriate behaviors. I'm not contending that the feeling of "presence" is not integral to behavior, I am just saying that there is no firm evidence to show that a profound feeling of presence is truly necessary to get tasks performed. Perhaps my attitude reflects (too much) my own interests, which is improving interfaces and human-machine interaction in real world systems. If someone would show me that pilots (say) perform much better when they report a feeling of presence from their displays, than when they are aware that their displays are just that, displays, then I would be the first one calling for VR type systems in the cockpit, etc. The fundamental question (when designing for performance, rather than for entertainment or other purposes), hasn't really changed, it is still, "what information is needed for best performance and in what format should it be presented?" I am happy to see the advances in VR, should we ever find that the answer to the above question is that we need not only the information but the phenomenonological aspects of presence too. That may happen, but then again it may not. If I am correct that this is still an open question, then to me VR remains a (very interesting) technological opportunity, but by no means the solution to the many interface design problems we have today. The problem, of course, is that it is not clear that presence for presence sake is really such a good thing. My guess is that presence will cut both ways, that when things are going well they will go quite well, but errors and misunderstandings will be amplified in intensity as well. So, our pilot has presence for example: Now, instead of thinking (incorrectly) that his left engine is out, now he is "fully experiencing" (incorrectly) that his left engine is out. I guess the bottom line for me is that I like to see problem-driven rather than technology-driven solutions to real world design problems. But I realize that the potential applications of VR are much broader than my own area of interest. I would, though, like to see comments on what is "really" driving the move to realism and presence. Alex UUCP: kirlik@chmsr.UUCP {backbones}!gatech!chmsr!kirlik INTERNET: kirlik@chmsr.gatech.edu
kirlik@chmsr.gatech.edu (Alex Kirlik) (10/22/90)
In article <9638@milton.u.washington.edu> dmark@acsu.buffalo.edu (David Mark) wr ites: > Comments on the beneficial role of abstraction deleted. > >So to rephrase my original question, has the Virtual Reality community >addressed the issue of how real the presentation should be, and when the >presentation to the user should be simplified and selective? > I, too, am interested in this issue, but for a slightly different reason. Although any attempt to characterize a young field like VR is certainly going to be dangerous, I will say that most VR research is addressing mainly the phenomenological aspects of perception, as opposed to the cognitive aspects (I realize even this distinction is far from clear). What I am concerned about, here, is the lack of empirical evidence that shows that creating a feeling of "presence" or "here-now-ness" is really beneficial from the standpoint of the *performance* of a user at a given cognitive task. As I am concerned with interface design and human-machine interaction in real world systems, the reason I worry about this issue is that I suspect that aiding the phenomenological aspects of perception through VR might cut both ways, when it comes to actual human performance. A pilot, for example, might now errorneously believe that his or her left engine has flamed out, but with VR he or she might then erroneously "fully experience" that the left engine has flamed out. We are always going to be at the mercy of sensor technology and hardware malfunction in human-machine systems of realistic complexity, and given this it is not clear to me that creating felt presence will always be beneficial. Perhaps when extending perceptual abilities through technology, we may actually want the person to realize he or she is looking at information displays rather than fully experiencing the state of the system. My comments do not speak to the issue of VR for other purposes (such as entertainment and other non-critical visualization tasks), but as my comments above suggest, I am concerned about certain claims for VR made that suggest that it is a promising solution to real-world interface design. Felt presence may or may not prove beneficial, and to me this issue remains wide open when we consider actual cognitive performance. I know of no good data that suggests that a person actually performs better at a task when that person also reports felt presence, but I would be very pleased to hear otherwise. Alex UUCP: kirlik@chmsr.UUCP {backbones}!gatech!chmsr!kirlik INTERNET: kirlik@chmsr.gatech.edu
danorman@UCSD.EDU (Donald A Norman-UCSD Cog Sci Dept) (10/22/90)
In article <9638@milton.u.washington.edu> dmark@acsu.buffalo.edu (David Mark) writes: ^Has the "Virtual Reality" (VR) community addressed the issue of when something ^might be "too real"? ^... a road map is better for finding one's way around ^in a city than would be an airphoto, even an airphoto with street names ^overlain. The utility of the road map in such situations stems from the ^fact that it is a *selective* representation of reality. Roads are emphasized ^and most other features are suppressed. In fact, it may be claimed that ^this selection, symbolization, and simplification is the essence of ^cartography. ^ This is a critical point. The nice thing about a virtual or artificial reality is that it can be better than real: reality is harder to deal with than pre-processed information, especially symbolic pointers, line drawings, and cartoons. In a virtual reality, wouldn't it be nice if the path one was trying to follow were shown as a yellow dashed line (perhaps flashing), and if the items that could be perceived along the way had nametags or special symbology associated with them. But as Mark points out, this is stilt hard to perceive (in part, i believe because of the clutter and because real objects and real photos do not have boundaries and contours clearly visible). If I need to find my way, why not let me switch the perception of a rich, three-dimensional world, to a preprocessed, three-dimensional cartographic representation: 3D maps aren't possible today, but they could be with VR technology, one that would even show me my own position on the map. (actually, 3D maps do exist as perspective drawings of cities and mountains. But note that in these drawings, one has to distort the scene to make it more effective, especially the vertical dimension, and sometimes moving items around so as to make the things behind them visible. The exciting part about virtual or artificial realities is that they could have processing aids associated with them -- cognitive artifacts, if you will -- so that these artificial realities might be easier to perceive and deal with than true realities. Don Norman INTERNET: dnorman@ucsd.edu Department of Cognitive Science D-015 BITNET: dnorman@ucsd University of California, San Diego AppleLink: dnorman La Jolla, California 92093 USA FAX: (619) 534-1128
cyberoid@milton.u.washington.edu (Robert Jacobson) (10/22/90)
I'm not sure that Alex's claims -- that there is no research to show that the experience of "presence" leads to improved behavior -- will stand. First, there is an extensive corpus of literature produced by Tom Furness at Wright-Patterson AFB, during the late 1970's and 1980's, that demonstrated that pilots DO perform better where there is a feeling of presence. Second, architects and planners are well-acquainted with the "haptic" sense, by which places are perceived and appreciated through synergetic sensory inputs -- the so-called "whole body" experience. "Realism" might be construed as more than better resolution of visual images. It might also require correct approximation of spatial relations in several fields (visual, aural, gravity, etc.). If the latter interpretation holds, than current "real world systems," which do not provide for these orientations, might not be very real at all. Thanks for allowing me to doff my critic's hat for a moment. Now, back to moderation. Bob Jacobson Moderator
kirlik@chmsr.gatech.edu (Alex Kirlik) (10/23/90)
In article <9684@milton.u.washington.edu> cyberoid@milton.u.washington.edu (Robe rt Jacobson) writes: > >First, there is an extensive corpus of literature produced by >Tom Furness at Wright-Patterson AFB, during the late 1970's and 1980's, >that demonstrated that pilots DO perform better where there is a >feeling of presence. Thank you for the pointer, I will have to try to get access to this work. Also, let me apologize for the 2 redundant postings, as I did not realize this group was moderated and I though my first posting was lost when it did not appear. Also, I'd like to say that I am enthusiastic about the potential of VR and perceptual enhancement in general to solve certain human-machine interaction problems. My own view is that much of the observed cognitively intensive and error prone activity one sees in complex systems results from the operator's attempt to cope with perceptually impoverished (or at least perceptually innapropriate) interface conditions. A good amount of time and effort has gone into exploring aiding concepts and training methods as potential design solutions, but relatively little effort has been spent on the alternative, namely creating interfaces that eliminate the need for certain of these cognitively intensive error prone activities in the first place. I think VR, visualization, etc. has the potential to make a real contribution in this area. The reason for my original posting was, that when I am asked to defend the design approach outlined above the objection is sometimes raised that we might eliminate some of the cognitive-level errors and biases but introduce a new set of errors and biases, related to both the cognitive and experiential aspects of perceptual function. I still think that the perceptual enhancement approach is on the right track, although I take these objections seriously and would like to have more data on this issue. One reason one must be careful when looking at flight simulation research (and I don't mean to prejudge the research mentioned above, I am speaking of other simulation research with which I am familiar), is that it is not clear how to attribute the causes of enhanced performance to properties of the simulator interface/environment. Much of this research uses experienced pilots as subjects, and I suspect that the reason that performance is better when subjects report felt presence is that presence enhances the transfer of previously learned skilled routines to the flight simulator environment. In these experiments, then, it is not presence for presence sake that may be enhancing performance, but rather it is the realism that allows for positive transfer of learned skills. An interesting issue is whether realism promotes felt presence and this promotes transfer/performance, or whether both felt presence and transfer/performance are two independent effects of realism, although this is a quite different issue. In those experiments using skilled subjects in simulations of the environments in which their skills were acquired, then, it may be difficult to parcel out the effects of felt presence on performance and the effects of positive transfer, in my opinion. I do, though, intend to take a look at the simulation research you mentioned. When designing new interfaces/systems where we are not relying on the transfer of previously learned skills, it still may be the case that felt presence enhances performance, but as I conjectured previously I am concerned that presence may have the potential to have both beneficial and deleterious effects. In certain systems, we may even want to discourage the transfer of innefficient previously learned skilled routines. In tasks such as locomotion (driving, flying etc) we are implicitly relying on the transfer of very- previously learned routines, those evolved to help us get around the world, and here I am reasonably confident that felt presence will correspond with good performance when designing interfaces. For decision-making, problem- solving, and the like, though one must be pretty confident in how the cognitive task has been mapped to a perceptual-motor task, and what the new performance limitations and biases introduced might be. Thanks again for the pointers and the comments, Alex UUCP: kirlik@chmsr.UUCP {backbones}!gatech!chmsr!kirlik INTERNET: kirlik@chmsr.gatech.edu
bro@eunomia.rice.edu (Douglas Monk) (10/23/90)
In article <9682@milton.u.washington.edu> danorman@UCSD.EDU (Donald A Norman-UCS D Cog Sci Dept) writes: [VR can be better than real :] >[...] reality is harder to deal with >than pre-processed information, especially symbolic pointers, line >drawings, and cartoons. Part of the fascination with VR may be the violations of real constraints that it makes possible: adolescent power fantasies take on a whole new dimension. In a real sense, some of the attraction that the movie "Who Framed Roger Rabbit?" had for me was the interaction of "real" characters and "virtual" cartoon characters. But the most fascinating thing of all was the "virtual" reality of Toontown: an entire environment in which none of the laws of "reality" necessarily applied, but in which humans could still meaningfully perceive, act, and react. The "cartoon" is used to *simplify* reality, and to *supplant* portions of it, and to do so in a cost-effective way. Taken to extremes, the simplification and supplanting would render the environment *useless* from a human viewpoint (except perhaps for aesthetic concerns). On the other extreme, if one spends tremendous amounts of time and money *duplicating* reality, VR is a waste of both: it would be cheaper and more efficient just to do whatever you needed to do *in reality*. The true practical benefits from VR come from the *"cartoon"* aspects of it, not from the *"real"* aspects: do it cheaper or easier (simplification) or do the impossible (supplanting natural law). (Aesthetics==Art as goal is another discussion.) Doug Monk (bro@rice.edu) Disclaimer: These views are mine, not necessarily my organization's.
hlr@uunet.UU.NET (Howard Rheingold) (10/23/90)
danorman@UCSD.EDU (Donald A Norman-UCSD Cog Sci Dept) writes: >This is a critical point. The nice thing about a virtual or artificial >reality is that it can be better than real: reality is harder to deal with >than pre-processed information, especially symbolic pointers, line >drawings, and cartoons. >In a virtual reality, wouldn't it be nice if the path one was trying to >follow were shown as a yellow dashed line (perhaps flashing), and if the >items that could be perceived along the way had nametags or special >symbology associated with them. Stephen Ellis at NASA explained this to me in terms of the difference between a visual *display* and a visual *instrument.* That is, when you are dealing with docking maneuvers in 3 space, for example, and the path the pilot wants to see is in essence a virtual path that takes into account present trajectory, burn length, movement of other objects, etc., what you need is a display that is designed specifically to distort information in order to help the pilot make judgements. In aviation, truth might be more dangerous than a representation that is designed to take human perceptions into account (humans, for example, tend to make certain mistakes in judging azimuth with their unaided visual perceptions -- a display that includes a certain amount of distortion in these instances might lead to better judgements by the human pilot). These issues, and other perceptual issues relevant to VR, are discussed in "Spatial Displays and Spatial Instruments," proceedings of a conference sponsored by NASA, held at Asilomar in 1987. The NASA publication number is NASA CP-10032