Posts Tagged ‘Rittel’

20+ years on from gIBIS and QOC

December 2, 2011 8 comments

The Issue-Based Information System (IBIS) approach to capturing and using design rationale is one of the leading design theories that addresses how groups identify, structure, and make decisions during the problem-solving process. IBIS was conceived by Horst Rittel in the 1970s as a way to deal with what he called wicked problems, unique and novel problems with no stopping rule or “right” answer. IBIS was the first of many argumentation-based solutions—spawning or directly influencing instantiations that include PHI, QOC, DRL, gIBIS, and Compendium—with a common trait that outlining the problem space is equivalent to outlining the solution space. This post outlines the evolution of these design approaches, briefly exploring some key questions about when these approaches are (and aren’t) well-suited, particularly for the field of human-computer interaction.

Two writings were central to this historical review, connecting to all the other papers referenced here: Hypermedia Support for Argumentation-Based Rationale: 15 Years on from gIBIS and QOC by Buckingham Shum, Selvin, Sierhuis, Conklin, Haley, and Nuseibeh (the title of which inspired this post’s title); and Rationale Management in Software Engineering: Concepts and Techniques by Dutoit, McCall, Mistrik, and Paech. And a great many more readings were highly influential and enlightening: the classic “Design Rationale” book by Moran and Carroll that captured the 1996 state-of-the-art for the design rationale field, the recent pair of special issues of the Human Technology journal on Creativity and Rationale in Software Design, and ongoing practitioners’ views on wicked problems and IBIS via blog posts and white papers by Paul Culmsee, Kailash Awati, Jeff Conklin, and others I’m surely forgetting.

Rittel is often pointed to as the initiator of design rationale due to a series of papers from the early 1970s to the early 1980s. He laid out an extensive definition for wicked problems, featuring ten distinguishing properties, with Melvin Webber in a 1973 paper Dilemmas in a General Theory of Planning (though Rittel and his colleagues had been discussing the issue and postulating approaches for at least five years prior to the paper). Other Rittel papers suggested that the right approach to address wicked problems was through issues, situationally-dependent questions that are “raised, argued, settled, ‘dodged’, or substituted” during a design session. Rittel’s concept of an issue is core to his Issue-Based Information Systems (IBIS) approach to group design and decision making, in which issues start a questioning process that links each issue with facts, positions, arguments, and other structures through knowledge relationships. The result is a knowledge space that doesn’t solve the issue, but rather creates an environment of “support” and “planning” where people better understand each others’ points of view.

IBIS was refined and simplified in subsequent years, and the IBIS tree-like structure led to many automated tools. Rittel’s student Ray McCall created a Procedural Hierarchy of Issues (PHI) refinement to IBIS that included many of the early tools: PROTOCOL, MIKROPLIS, PHIIDIAS, and JANUS. Other approaches to design rationale management drew inspirations from this early IBIS/PHI work: QOC by McLean, Young, Bellotti, and Moran; and DRL from the work of Potts and Bruns and of Lee. Perhaps the first widely-used tool was gIBIS, a graphical IBIS tool developed and popularized in the 1990s by Jeff Conklin and his collaborators, and its follow-up tool QuestMap. Much of the reflective literature on design rationale groups these techniques together, with Dutoit et al. noting that “there are so few significant differences in the schemas of IBIS, QOC, and DRL” (though there’s an excellent detailing of the differences in that paper). In general, these tools tended to be less intrusive than the original IBIS approach (e.g., less formality, resulting in simpler structures) and more prescriptive outcomes (with specific solutions). This simpler model enabled more immediate value to the participants, for whom value from the tool was imperative for any time investment.

Conklin joined with numerous other researchers and practitioners—Simon Buckingham Shum, Al Selvin, and others—to create the most current and widely-used instantiation of the IBIS ideas in the Compendium dialog mapping tool. I discussed Compendium in a previous tool review post, though I didn’t use it to its fullest capacity—in a collaborative situation in which divergent opinions need to be drawn together toward a common understanding. The big issues that I had with Compendium were with scalability and history: it’s hard to see more than a dozen nodes at once, and support for rolling back to previous views was limited. But it’s much more usable than gIBIS, and it seems to have attracted a fairly sizable following among usability consultants. Features like scalability and history don’t seem to be a focus of the Compendium tool. In fact, it seems that the biggest contribution of Compendium is not in how knowledge is represented (which had been done before) or in how it is manipulated (simplified…or in some cases ignored or deferred to a future version of the tool), but in the social processes around how the tool is used: an expert in knowledge management and the IBIS/Compendium provides real-time guidance during the analysis process, toward helping the participants debate directions moving forward.

In summary, two related trends that I notice in these IBIS-based tools are that (1) the “hard” stuff is left for experts; and (2) the approaches seek more immediate value to designers. Perhaps this is a response to a shift from academia to consultant environments—consultants certainly need to carve out an “expert” role for themselves, and they’d better make sure there’s value to the participants at the end of the day.

Another trend from IBIS to QOC to gIBIS to Compendium is that the approaches seem to be increasingly question-driven—as opposed to issue-driven—with progressively fewer structuring options for the knowledge that is generated. Does the path of simpification and certainty of IBIS tools violate the original wicked problem mandate that problems don’t have solutions, merely different states of being? Or does the simplification actually match the vision of wickedness that Rittel initially posed? I worry that the increasingly tree-like structure of many of these graphs draws designers further away from the initial problem and doesn’t encourage revisiting issues (though I’ll acknowledge again that Rittel’s original IBIS graph (non-tree) structure with its many loops and cycles is far harder to understand).

One big drawback I see with all of these approaches is their inability to deal with the changing truth that occurs in most design efforts and is prominent in the field of human-computer interaction. I think that’s central to my issues with Compendium and other tools—regarding scalability and history—in which problem spaces become more complex over time. Lots of factors—the state of technology, the skill sets of the designers, the knowledge, skills, and acceptance levels of the target user population—change over time, and decisions that were made at any single point may not apply later. Recall two other key feature of wicked problems: that solutions (or problem states) aren’t right or wrong, and that there’s no stopping rule. Popper, as paraphrased in Rittel and Webber’s 1973 paper, suggested that solutions to problems should only be posited as “hypotheses offered for refutation”; otherwise, you can end up pursuing tame solutions to wicked problems.

Finally, we must be careful that we’re not reducing the wickedness of a problem to the creation of a claims map, or the mapping of a dialog, or the removal of storms from brains—in effect, turning the wicked problem into a tame one. Or, if we choose to do that, we must ensure that, when a design team goes back to look at a DR representation, each element in it is appropriately questioned. Sometimes computer tools can hurt in that regard—they help designers violate some tenet of wickedness by providing a “memory” that captures truths that don’t exist, or by encouraging the capture of knowledge at the wrong granularity.


Compendium review

October 7, 2011 8 comments

Compendium is a hypermedia mapping tool created by a consortium of universities and research labs in Europe and the US. It is rooted in Rittel’s wicked problem conceptualization and IBIS approach to design and design rationale capture, building on combined efforts of Al Selvin, Simon Buckingham Shum, Jeff Conklin, and many others. Compendium allows designers to create a node-link graph of interrelated concepts, including questions, ideas, pros and cons, references, and decisions. It’s similar to a lot of the mind map tools that are out there, though its scientific basis makes it

I downloaded Compendium (version 2.0b1) and used it as part of a personal brainstorming session. I wanted to exercise the things that could be done with Compendium, then share my results with a remote group of colleagues–as seems to be the great strength of Compendium. Specifically, I wanted to explore how an app or set of apps on mobile interfaces can be used to encourage physical activity among K-12 students (mainly middle schoolers)–assuming each has a phone with the apps installed. We’ve come up with a small handful of games and activities ourselves, and we’ve been inspired by the process and products from the SICS-Microsoft “Inspirational Bits” effort. What we need is ideas, and that why I turned to Compendium.

It was a bit slow to get started using Compendium–even/especially with the 42-page (!) getting-started manual (though there’s also a 2-page quick reference sheet as well, which was helpful once I had a basic understanding of Compendium). There are the typical “starting-with-a-blank-slate” problems where the initial actions aren’t obvious, full of “aha” moments as I played around with it. The palette of nodes on the left of the screen was helpful–but clicking on them does nothing (aha, you can click-and-drag them onto the screen). I couldn’t quickly figure out how to link elements (aha, it’s not just a click-and-drag motion, that’s for moving nodes, it’s a right-click drag motion for linking). Hitting return when I finish typing a node name pops up a node dialog instead of just naming the node (aha, I can click elsewhere to defer adding node details).

My first pass in using the tool resulted in a single question and around 8-10 ideas that address the question. For better or worse, I then felt compelled to use other nodes–namely, the “pro” and “con” nodes (that are quite similar to the upsides and downsides of claims). I considered using the other nodes, but they didn’t seem as applicable–I didn’t want to “decide” anything, and I didn’t delve deep enough to include any references or videos or web sites. Alternating between ideas and pros/cons worked out well, as thinking about pros/cons typically inspired other ideas, and thinking about new ideas led to new pros and cons. Being a good engineer, I ended up with a four-level tree: a question at the root, four idea categories, a bunch of ideas, and a bunch of pros and cons for each idea.

The layout aspects of Compendium are a major weakness of this tool. There’s an automatic layout feature, but it seems to use a poor layout algorithm…thus there’s no way the Compendium graphical representation could support a large node set (beyond 20-30 nodes) that would emerge from many brainstorming sessions.
For example, my 25-node graph, created in a few hours of thinking about, interconnecting, and evaluating ideas–couldn’t fit on the screen either horizontally or vertically in a readable manner. The zoom isn’t very smart, simply shrinking the nodes and thus losing the context that goes with them (rather than, say, keeping the icons visible and/or 1-2 keywords readable) and it doesn’t seem to be possible to zoom down only a portion of the graph. There are so many great graph layout algorithms, and so many ways to lay out and zoom graphs (e.g., radial, fisheye, hyperbolic), that it feels very limiting not to have them available in this tool.

The computer-supported features of Compendium are what I feel makes it worthwhile. When I “lost” a list that I created, I was able to search for it to locate the node where I stored it. You can limit search just to the visible nodes or extend it to embedded lists, notes, etc. The search also extends to deleted nodes, so as a project ages I could have found ideas from weeks or months before. There seems to be some sort of back/forward buttons and history bar which (I assume) allow you to revert back to previous versions of the page–but I couldn’t get this to work. A well-implemented history feature seems like one of those things that would really be worthwhile; e.g., to view what transpired between the beginning and end of last week’s meeting, or to revert back to the state of inquiry from the start of the meeting. But a well-implemented history also seems hard to implement!

After completing a Compendium graph, I sent it to my six remote colleagues, both in HTML form (which can be viewed by any web browser) and in XML form (which could be loaded if you install Compendium). Two of the colleagues responded back, both of whom seemed to look at the HMTL version but not the XML version. There were positive comments about the ideas that emerged, though little specific. One of the two seemed interested in using it in a design session on her end, so I may update this paragraph with more details (and if there are comments from the other collaborators).

Any sort of design tool has overhead associated with it. At times I suspect a paper version of Compendium might be better, at least from a usability standpoint. When leading a design session, I want to get ideas up there quickly, I want to move them around quickly, I want to stack them and move them around and hand them to breakout groups to flesh out themselves. Those sorts of things seem to go faster with Post-Its than with Compendium. And I don’t think it’s the fault of Compendium–I noticed the same sort of thing with PIC-UP (from our lab) whereby the richer and more communicative interactions occurred with paper versions of cards. Of course, those were short one-off sessions, and I suspect the real value of tools like Compendium lies in its use over long periods of time.

Compendium has been widely used, and there are tons of comments on their web site. Compendium’s heydey seems to be the 2003-2007 time frame, when there was an annual meeting on it, and there were lots of case studies and papers emerging about it. It’s certainly still active–the beta version that I tried was released earlier this year–but much of the web site seems dated, and there’s currently no formal support for the tool (though there’s a somewhat active online forum for reporting bugs). It’s hard to judge how large and active the user community is right now, but historically there’s been a fair amount of use.

So is this a good tool? I think it can be great for the right type of situation–when you want to save and revisit and search a collection of ideas, and when you need some encouragement to balance questions, ideas, pros and cons, and associated rationale. The tool really guides you to do these things, and if you’ve got a task that could benefit from it then it can really be worthwhile. And a final note: Compendium seems to be one of those “all-or-nothing” tools–if you buy into its philosophy, there can be great value…but you have to buy into it. The project leader must decide that Compendium will be used, and the team members must agree to use it during their design. If you’ve just got a small portion of the team using it, then the results won’t be nearly as meaningful. But if everyone is on board, it can be a great repository for design.

McCall meeting

September 13, 2011 Leave a comment

I had a wonderful conversation with Ray McCall and Clayton Lewis last week, in which we discussed directions for design rationale generally, and for claims as a key element in design rationale specifically.

Ray was a student of Horst Rittel at UC Berkeley during the late 1970s–an architect by training who is in a UC-Boulder/UC-Denver professor position in architecture and planning. He’s worked with Clayton Lewis, Gerhard Fischer, and Anders Morch here at UC, and he’s written and edited several books on design rationale with Jack Carroll, Janet Burge, and other software engineers.

Ray created his own version of IBIS called PHI (procedural hierarchy of issues), building on the notion of issues in IBIS to create an argumentative structure (not unlike one purpose in claims creation). He was really plugged in to the design rationale ideas of the 1970s, 1980s, and 1990s–JANIS, Alexander’s Timeless Way of Building, Marshall & Shipman’s schema-based elicitation arguments–and he’s stayed up on the more recent approaches from the software engineering domain.

One key idea from the session was Ray’s suggestion that claims upsides and downsides are too polarizing–too likely to prejudice a designer toward thinking of an effect as positive or negative, when it may be quite different in a different context. As an example, a claim might suggest that a blinking light is interruptive (a negative) but it might be a positive when interruption is desired.

One piece of career advice from the session I’ll oversimplify as such: “be Tim, not Ted”. Ted Nelson, the father of hypertext, makes interesting and provocative arguments about the lack of scalability in the web, the poor granularity choice of a “page”, and the lack of bi-directional links. But by many reports he doesn’t compromise on his vision for the web, and his Xanadu system has been described as the longest-running vaporware system of all time. Contrast that to Tim Berners-Lee, father of the World Wide Web, who essentially gave away his idea to ensure a widely used product. It’s tough to compromise–especially when you’re right–but sometimes it’s the right thing to do. Sometimes!