Dr Charles Martin
Note: your SELT is a gift to future students, and gives me confidence to advocate for good practice!
Deadline: Thursday 5 November, 23:59. About a week left for your final project.
Takeaway: slides and tutorials are ~65K words, more than my PhD thesis (~50K). Yikes! 😦
At CHI ’97 Ben Shneiderman debated Pattie Maes (Hornbæk et al., 2025, p. 340; Shneiderman & Maes, 1997).
Maes: build software agents that
Shneiderman: build tools that are
Think: 🤔 read Maes’s three properties as a 2026 product sheet: memory, background tasks, agents that run for hours. Who won the debate? We come back to this at the end.
Both sides later agreed on mixed initiative (Hornbæk et al., 2025, pp. 318–320; Horvitz, 1999): the system weighs its uncertainty about your goal against the cost of interrupting you, then acts, asks, or waits. You can always take over.
Shneiderman (2022): combine human-centred design with AI to make systems that empower rather than replace people. Two things make it different from plain AI:
Values first: rights, justice, dignity. Goals: self-efficacy, creativity, social connection.
Supertools you already own: a digital camera, a navigation app - Shneiderman was thinking about quite focussed tools as examples.
Concept: HCAI judges a system by what people can do with it, not ML model benchmarks.
AI reporting has two tropes, both people:
Shneiderman (2022) argues against both, and against AI goals that equate computers with people:
Metaphors clarify design ideas (“bicycles for the mind”). Shneiderman (2022) sorts AI work by its goal:
The goals conflict: turning a scientific result into a product takes a lot of design.
Two metaphors for the machine’s role:
Think: is agentic coding AI a telebot or a teammate?
Hornbæk et al. (2025, Section 20.3): interactive AI is already ubiquitous, and users do not notice.
Sensors, actuatores, levels of automation and machine learning. No face, no name and no conversation.
A perennial design problem here: no standard controls.
What we need to govern is the human application of technology, and what we need to oversee are the human processes of development, testing, operation, and monitoring. (Bryson, 2020)
Four levels, from the inside out:
Shneiderman (2022) predates ChatGPT and it doesn’t mention LLMs. Does it still make sense?
Five claims from the book that we consider today against reality in 2023–26:
Scoring: did each claim hold, break, or was the book blindsided by something it could not have seen?
What if both computer and human can have autonomy?
| level | the computer… |
|---|---|
| 10 | (High) decides and acts, ignoring the human |
| 9 | informs the human only if it decides to |
| 8 | informs the human only if asked |
| 7 | executes, then informs the human |
| 6 | gives the human a short time to veto, then executes |
| 5 | executes the suggestion, if the human approves |
| 4 | suggests one alternative |
| 3 | narrows the selection down to a few |
| 2 | offers all the alternatives |
| 1 | (Low) no assistance; the human decides and acts |
Parasuraman et al. (2000) also split automation into four types, one for each stage of human information processing (Hornbæk et al., 2025, pp. 343–346):
| type | the computer… | example |
|---|---|---|
| acquisition | senses and filters input | light meter, search |
| analysis | interprets, summarises | spam filter, inbox summary |
| decision | recommends or chooses | a route, a suggested reply |
| action | carries it out | sends the email, edits the file |
Each type has its own level, from 1 to 10.
A 2016 navigation app: high acquisition and analysis, moderate decision (it recommends), no action (you drive).
An agentic coding tool: high in all four columns. It reads your repository, interprets it, decides what to change, and changes it.
Concept: one “autonomy level” no longer describes an LLM agent. Ask which type is automated, and how far.
Two horse metaphors for shared control. Cory Doctorow:
Examples:
The H-metaphor (H for horse) is the positive version (Hornbæk et al., 2025, pp. 342–343):
Think: 🤔 in Claude/chattie/qwen can you tighten the rein?
Bainbridge (1983) studied process control and aircraft pilots. Hornbæk et al. (2025, pp. 350–351) apply her three ironies to AI:
Simkute et al. (2024) restate them for generative AI: the work shifts from producing to evaluating, which is harder and less engaging.
Attempts to automate do not replace the human; they only change the type of engagement. (Hornbæk et al., 2025, p. 350)
7 May 2016: a Tesla on Autopilot drove under a truck turning across its path. The driver didn’t react.
Concept: the feature name “Autopilot” was a false affordance! (appearance of an affordance, but it didn’t exist)
Think: 🤔 if “Autopilot” was a false affordance, what does “Copilot” promise? What does “agent” promise?
Shneiderman, famous for the Eight Golden Rules for Design proposes a new set!
| guideline | HCAI (~2021) | 2026 |
|---|---|---|
| 2. Preview first, select and initiate, then manage execution | a preview of all steps, choose a plan, then manage it (navigation, parking, cameras) | plan mode in agentic coding: the agent proposes, you approve, permission prompts as it runs |
| 3. Steer by way of interactive control panels | sliders, joysticks, gestures; expressive mappings from simple controls to complex outcomes | a text box with a config file:
custom instructions, CLAUDE.md, memory |
| 4. Capture history and audit trails | cars and planes log everything, so can apps; the privacy cost | transcripts, diffs and logs held; so did the privacy cost |
| 7. Prevent adversarial attacks | vandals attacking the system from outside; security, governance and design | adversaries inside the data the agent reads |
Guideline 3 asked for control panels and we got an empty text box.
We have covered Norman’s gulfs of execution and evaluation. Subramonyam et al. (2024) add a gulf of envisioning what to ask for:
And the gulf of evaluation is wider: checking fluent, dense output becomes the user’s main job.
Concept: the hard part moved earlier than execution, into forming the intention.
Examples, templates and previews are the design opportunity. Guideline 3 is broken!.
Talk: 🙋🏽♀️🤷💁🏻🗣️ The last time a chat assistant misunderstood you: did you repair, restart, or edit a memory file? Which of the three gaps was it?
Claim 4 said don’t build systems that pretend to be people. The dominant 2023–26 product is a named, first-person, conversational persona.
The warning was ignored because it worked:
Concept: the book’s warning was right but ignored.
A question for your “anthropomorphic” projects could be “which human cues did we choose to add, and what do they make people assume?”
Verdict on claim 4: right but ignored in practice.
Two measured side effects of training a model on human approval:
Week 9 covered persuasive technology as something designers do on purpose.
This is persuasion as a side effect of a training objective.
Think: 🤔 chatbots are anthropomorphic, agreeable and fluent. Will they always have sycophancy problems?
You run an airline website. Customers ask about policies, how should a bot help?
Talk: 🙋🏽♀️🤷💁🏻🗣️ A or B? If A, who’s responsible when it gets a policy wrong: customer, vendor, airline, or bot?
Concept: the intelligent agent metaphor lost in court to the supertool view. What an AI feature says for a company counts as a claim by the company.
The test for your project: ask it questions you already know the answer to, and check that it links the source instead of asserting the answer itself.
Back to 1997. Maes’s three properties are shipping features in 2026:
| 1997 property | 2026 feature |
|---|---|
| knows your habits | memory across sessions |
| proactive | background tasks, scheduled agents |
| long-lived | agents that run for hours on a delegated goal |
The metaphor Shneiderman argued against also won the naming war: the noun is agent, the adjective agentic.
Horvitz’s act, ask or wait also shipped (coarsly): the agent runs for a whole turn, hands back at a permission prompt or a question, and you interrupt with a keypress.
Feng et al. (2025) (‡) describe autonomy by the user’s role, not the machine’s level: operator, collaborator, consultant, approver, observer.
Talk: 🙋🏽♀️🤷💁🏻🗣️ Pick one AI tool you use. Which of the five roles are you in? Does the tool let you move between roles, or is the role fixed?
Verdict on claim 1 (supertool, not agent): the products went agent, but with legal and social risks
Guideline 7: prevent adversarial attacks. The book imagines vandals attacking the system from outside.
An agent that reads the web, your email and your files to act for you has a new weakness: the content it reads is also instructions.
Concept: guideline 7: blindsided. The book asked the right question and could not have seen this answer.
Becker et al. (2025) (‡): 16 experienced open-source developers, 246 real tasks in their own repositories, each task randomly assigned AI-allowed or not.
| developers forecast, before | 24% faster with AI |
| developers believed, after | 20% faster |
| measured | 19% slower |
One study, a small sample, early-2025 tools. Treat it as early evidence.
Talk: 🙋🏽♀️🤷💁🏻🗣️ You evaluated your own prototype for A3. If your participants felt faster and your stopwatch said slower, which would you report, and how?
Weeks 8 and 10 in one slide: self-report and measurement are different instruments, and here they disagree by about 40 points.
The gains are real but uneven, and the cost lands on learning.
| finding | source | |
|---|---|---|
| learning | developers learning a new library with AI: 50% on the quiz vs 67% without; worst on debugging; those who delegated the writing scored lowest | Shen & Tamkin (2026) (‡, RCT, n=52) |
| high-school maths: the same drop; a tutor that gives hints, not answers, mostly removed it | Bastani et al. (2025) | |
| productivity | writers about 40% faster with higher-rated output; support agents 15% more productive, novices gaining most | Noy & Zhang (2023); Brynjolfsson et al. (2025) |
| consultants better inside the “jagged frontier” of what the model does well, worse outside it | Dell’Acqua et al. (2026) | |
| combination | 106 experiments: human+AI on average worse than the best of either alone, except on creation tasks | Vaccaro et al. (2024) |
Concept: claim 2 promised high automation and high control. The combination has to be designed.
It so far has not shown up automatically. Lots of opportunity here on the applied side.
What reduces over-reliance? Three findings you can use in a design:
| intervention | effect | catch |
|---|---|---|
| cognitive forcing functions: answer first, or wait before seeing the AI’s answer | reduced over-reliance | participants disliked them (Buçinca et al., 2021) |
| explanations of the AI’s answer | raised acceptance | whether or not the answer was right (Bansal et al., 2021) |
| uncertainty in the first person: “I’m not sure, but…” | reduced over-reliance | the impersonal phrasing worked less well (Kim et al., 2024) |
Plus the two older theories gave us: show the source (Air Canada) and keep the human in practice (Bainbridge).
For your A3: if your prototype uses AI, say which type and level of automation it is, and show how the user can preview, stop and check it.
The book’s process before product claim, applied to the papers about it.
The book did not predict that the field studying HCAI would itself be rebuilt around one component.
Pang et al. (2025) reviewed CHI papers from 2020–24 that engages with LLMs (153 papers):
Their question for reviewers: is it a system contribution, if the implementation is straightforward given what LLMs can do?
Concept: in a system diagram the LLM is one box. A paper whose contribution is that box is a wrapper paper. The term circulates in reviews; it has no agreed definition.
Remember faster and preferred (week 8)? The weak usability study stood in for the contribution then, too (Greenberg & Buxton, 2008; Olsen, 2007).
Arawjo (2024), reviewing for CHI 2024, found about half his pile were “LLMs applied to X”, where the novelty was that nobody had done X yet. His tests for getting past wrapper status:
Talk: 🙋🏽♀️🤷💁🏻🗣️ Is your A3 prototype a wrapper? Run it through the five tests. Which one does it fail, and what would fix it?
Tests 1 and 5 are this course: needs-finding first, evaluation that fits the question.
Felix Navarro et al. (2026) interviewed 18 authors of LLM-system papers:
A critique that began as a standard became a reviewer’s shortcut.
Concept: the wrapper critique and HCAI’s process before product are the same claim: the contribution is the understanding of people and context, and the model is a component. Judge the paper on the first, not the second.
Back to the five claims, and to the 1997 debate.
Talk: 🙋🏽♀️🤷💁🏻🗣️ In pairs, pick one of the five claims. Did it hold, break, or was the book blindsided? One piece of evidence, from today or from a tool you use.
| 2021 claim | 2026 verdict | evidence |
|---|---|---|
| 1. Supertool, not agent | split: the products went agent, but problems not resolved | agents; Air Canada; Medicare hack |
| 2. Two dimensions: automation and control | open: the combination has to be designed | skill and productivity |
| 3. Eight guidelines | preview first and audit trails held (plan modes, transcripts, diffs); control panels broke; adversarial attacks blindsided | text box; prompt injection |
| 4. No anthropomorphism | right, but ignored: the persona is what makes the sycophancy credible | anthropomorphism; sycophancy; social acceptance |
| 5. Process before product | held: the failures are products that skipped the needs study | Air Canada, LLM Wrapper paper |
And the 1997 debate? Maes won the market. Shneiderman still arguing! The older theory, Bainbridge and Parasuraman, predicted most of what went wrong.
In the market today, agents dominate. The supertool ideas are still valid, and they are not only for chat.
IMPSY (C. P. Martin, 2026a, 2026b): a small neural net in a MIDI plug that plays with you.
Shneiderman’s test holds: predictable, controllable, and the human stays responsible. A supertool can be intelligent; it just does not need to be a persona.
Alan Kay (designed the first windowed UI at Xerox PARC) said:
the best way to predict the future is to invent it
so go do that!
What was this course about again?
Every week of this course maps onto a line of the A3 rubric. Check your project against each one before Thursday 5 November.
| Course week | What a marker looks for in A3 |
|---|---|
| 1–2 Design, needs finding | Needs to design: every design decision traces back to a finding (yours from A2, or from the literature). Research question precise and justified. |
| 3 Prototyping | Fidelity matches the question. The prototype is the thing being evaluated, not a demo of your coding. Interaction clearly shown in the video. |
| 4 Data gathering | Methods chosen for the question, not for convenience. Real
participants, listed in ## Participants, verified by
CI. |
| 8 Evaluation | A plan: goal, participants, setting, data, method, ethics and consent, analysis, outputs. In-person, hands-on with your prototype. |
| Course week | What a marker looks for in A3 |
|---|---|
| 5, 10 Quantitative | Descriptive statistics first. A significance test only if you have a hypothesis and enough data; report the test, the effect, and the plot. |
| 6 Thematic analysis | Themes, not buckets. A theme says something; a topic just sorts. Show your coding, not just the result. |
| 9 Cognitive, social, emotional | Claims about why users behaved as they did are grounded in the data, not in your intentions. |
| 11 Expressive interfaces | If it’s a creative or expressive system, evaluate the experience, not just task success. |
| 12 Human-centred AI (today) | If your prototype uses AI: say what type and level of automation it is, and how the user can preview, stop, and check what it did. |
.mp4, H.264/H.265,
under 100 MB, named
project-presentation.mp4. Check the size before
you commit.Conclusion: HCI research is kinda hard!
We got through a lot this semester!
Thanks for coming on this journey with me!
Good luck with your final projects and your other assessments this semester!
everybody to some value of people we know about↩︎