Updated 16:45 December 31st 2023

Prof Harold Thimbleby …

1. Home page

Ticket machine
Harold using a ticket machine
— when it takes your cash
it does not confirm the ticket type

Press On book cover

Harold Thimbleby is See Change Digital Health Fellow at Swansea University, Wales.

He has just completed an exciting book on digital healthcare, Fix IT (click through to get a summary), which was published October 2021.

His passion is designing dependable systems to accommodate human error, especially in healthcare. See CHI+MED: Multidisciplinary Computer-Human Interaction research for the design and safe use of interactive medical devices for a major project he’s been on. See for some of his recent work in healthcare IT, and for recent coverage in the news.

Harold is an Honorary Fellow of the Royal College of Physicians, a Fellow of the Royal College of Physicians, Edinburgh, the Institute of Engineering Technology, the Learned Society of Wales, and an Honorary Fellow of the Royal Society of Arts.

Harold wrote the book Press On, which won the American Publishers’ Association best book award in computer science.

Harold is a visiting professor at UCL and at Middlesex University.

Harold’s web site (this site) is www.harold.thimbleby.net

Harold has been a Royal Society Wolfson Research Merit award holder and a Royal Society Leverhulme Trust Senior Research Fellow. He is Emeritus Gresham Professor of Geometry.


Please email me on harold@thimbleby.net

Prolific researcher

Harold published his first paper, on menus, in 1978, and has since written many publications: 365 refereed and 676 invited publications, from newspaper articles to articles in Encyclopedia Britannica; he has also given over 527 presentations around the world (as of February 2018). He wrote User Interface Design, published in the ACM Press Frontier Series in 1990, and his fifth book, Press On, was published by MIT Press in 2007, and was 2007 winner of the Association of American Publishers Publishing Awards for Excellence Competition in the Computer and Information Sciences category. He is currently See Change Fellow in Digital Health and has been Royal Society-Leverhulme Trust Senior Research Fellow (2008–2009), Royal Society-Wolfson Research Merit Award Holder (2001–2006). He was awarded the British Computer Society Wilkes Medal, and won a Toshiba Year of Invention prize.

Team builder

Harold founded Swansea University Research Forum, and founded the FIT Lab, 2006. He previously founded University College London Interaction Centre (UCLIC) in 2001.

International reputation

Harold has held visiting positions in Canada, New Zealand and South Africa, etc, and is on numerous international editorial boards and conference committees. He has presented in over 30 different countries. He gave keynotes at the first German Software Ergonomics conference, first International Handheld and Ubiquitous Computing Conference, first Asia-Pacific Conference on Human-Computer Interaction, and many more.

Excellent speaker

Harold is an ACM Distinguished Speaker and has presented over 600 debates, talks, keynotes, workshops and seminars (at Cambridge, MIT, Oxford, Royal Institution, Royal Society, Stanford and the House of Lords, etc). See more …

Advancing public understanding of science

Harold is 28th. Gresham Professor of Geometry, and has been widely interviewed and reported in the media. He had the largest post-bag ever for a New Scientist feature article — about video recorder usability. He has presented at many international science festivals in UK and internationally and at the Royal Society Summer Science Exhibition.


Harold’s full CV is available in PDF.

2. Tweets

3. Three passions

Green lane in Brechfa Forest
My Defender on a submerged, muddy green lane in Brechfa Forest
This sort of road is called a BOAT, a byway open to all traffic, but sometimes a boat would be useful too

1 Work — technology could be safer

Preventable error is blamed for killing many people in hospitals, and some of this is due to poor design of systems, particularly IT systems — whether patient record systems, databases, medical apps or conventional medical devices like infusion pumps, ventilators and glucometers. We’ve been doing a lot of work on making user interfaces to critical systems safer, and this (if any manufacturer or funder was interested!) would start to save lots of lives. Follow this link for more on this or this link for some articles I’ve written.
Click to download the full poster

2 Play — technology is fun

I’ve got a Land Rover Defender (110" TDci SW if you want to know) and have fun using it — it’s a very versatile vehicle. Elsewhere on my web site you can see me giving a lecture with the rear axle of a Defender, so it is serious fun, really!

3 Family — technology keeps us in touch

I have a wonderful family. Some of them have neat web sites — check out Prue’s on her work as an artist, and Will’s as a programmer, while Jemima is on pintrest and twitter and Facebook and … Sam and Isaac are probably lurking somewhere on the dark web for all I know. Isaac certainly has a machine-generated web site saying he is doing a PhD.

4. Three mysteries and a solution

My letter in The Journal of the Royal Society of Arts (p47, issue 2, 2015)
I find the following three things mysterious:
  1. Error in hospitals, if it was considered a disease, would be the third biggest killer after heart disease and cancer. Yet very little is being done about it. Compared to cancer, cybersecurity and big data research it has negligible funding. Why?

    Even the lowest estimates put preventable error as a much bigger killer than accidents; healthcare is the most dangerous industry! The higher estimate of error fatalities, 16.9%, is about double the lower estimate I used to make the chart above. Converting the percentages to the UK gives about 41,000 to 87,000 deaths a year (compared to around 2,000 on the roads). Whether you want to argue about details (drop me an email if you do), the figures are tragic.

    Some “error deniers” have told me that most people in hospital are going to die anyway. I think that’s like arguing that when a plane crashes most passengers were old people anyway. You can choose to fly or not fly, but few of us have a choice about hospitalisation. Why the persistent denial that it could be so much safer — and a much, much better environment for the people who work there?

  2. It is catastrophic when friends and relatives die. Sometimes, tragically they die as a result of an error, and if there isn’t an honest investigation and more research, more people will die the same way. Yet people donate to cancer research or kidney research, or whatever. Why not (also?) donate to error research? Since so little is spent on error research, every pound donated is going to have far greater leverage saving lives than donating, say, to cancer research where any donation is going to be a very small part of the total budget. I suppose people who die from most diseases have a long time to think about it, but error tends to kill people in minutes? (And very few errors are admitted, whereas it’s hard to deny having cancer.)

  3. Lots of user interfaces have bugs, yet nobody seems interested in fixing them. Bugs kill people, especially in widely used things like calculators which nurses rely on to calculate drug doses. See my poster for some simple examples.

    Some “bug deniers” tell me stuff is getting better all the time — and safer. Certainly it is getting more beguiling (even I want a new iPad!). But I haven’t seen good evidence that it’s getting safer; on the contrary it’s getting more complex, harder to use, and filled with more flaws people have to work around (if they notice the flaws, that is; God help us if they don’t).

    The best explanation is, I think, attribute substitution: it is very hard to decide what stuff is good (most user interface bugs are invisible to the eye and need serious thought to understand) so we substitute an easier criterion — does it look good. And most new things do look good — otherwise they wouldn’t sell! So our consumer eye is trained to mislead us into buying cute things that are unreliable and unsafe. And since we’ve already decided that the cute things are good, our eyes quickly glaze over when somebody tries to explain the real bugs.

    The second-best explanation is cognitive dissonance: you’ve spent a lot of money getting the system, and a lot of time understanding it, so you are going to think it is great. Otherwise you’ll have to admit you wasted all that time, money and effort! Ironically, the worse the system really is, the more the cognitive dissonance will mislead you.

And the solution is…

Here’s a very short animation explaining how to tackle the mysteries and improve the world. Have you got just two and a half minutes to spare?

5. News & recent things

A simple example of computer problems in healthcare
A simple example of computer problems in healthcare. The doctor’s name and address are truncated, creating unnecessary ambiguities — but my longer name isn’t trucated!

See more things …

6. Recent papers on healthcare, IT, and medical apps

Bugs in a CareFusion infusion pump
On this infusion pump, the rate is simultaneously shown as 0.02 mL/h and in an error warning as minus 0.1 (it’s exsanguinating!). What does the log say, and who will be to blame for any harm?
With thanks to my many colleagues: Paul Cairns, Abigail Cauchi, Ross Koppel, Paul Lee, Alexis Lewis, Karen Li, Patrick Oladimeji, John Williams, Albert Wu, and others.

Recent controversies over pandemic modelling

About cybersecurity, including WannaCry

General overview

Human error

Mostly about apps

Mostly about numbers

Mostly about infusion pumps

Other topics

7. Talking & speaking

Lecture at Royal Institution
Lecture at the Royal Institution
Getting to grips with maths using a Land Rover differential
— getting the next generation excited

Harold believes strongly that public understanding and awareness of technology and the science behind it is crucial for us to benefit from it to the full. He has been an ACM Distinguished Speaker.

He gives regular high-level talks on digital healthcare, for instance he gave one at the World Health Organization Global Ministerial Summit on Patient Safety

Harold was the keynote speaker at the “Next Generation Tour,” a research workshop that toured New Zealand Universities, inspiring undergraduates to take up research. He regularly runs conferences and workshops.

He has given over 80 conference keynotes and over 500 seminars and presentations (including at Cambridge, MIT, Oxford, Royal Institution, Stanford and the House of Lords) in 31 different countries.

Harold’s spoken at ten Edinburgh International Science Festivals, the British Association Annual science festival, Spoleto Festival, TECHFEST, Mumbai, Welsh Eisteddfods, and numerous Science Cafés, etc. Harold and Will Thimbleby exhibited an amazing new calculator at the Royal Society Summer Science Exhibition and at many other exhibitions.

Harold has written memorable advice for giving excellent presentations, which he calls Pirate Talks.

A selection of recent talks:

ACM distinguished lecture poster 1 ACM distinguished lecture poster 2

Here’s a selection of other recent talks and lectures:

See also Harold’s views on undergraduate teaching.

He has been widely interviewed and reported in the media. Harold gives numerous public lectures and school talks. He had the largest post-bag ever for a New Scientist feature article he wrote about video recorders.

8. Press On — the book

Press On
Press On

Harold Thimbleby, Press On — Principles of Interaction programming, MIT Press, 2007

Winner of the Computer and Information Sciences 2007 award from the Association of American Publishers

My book Press On was “Judged to be both innovative and rigorous, this volume teaches a conceptual framework and programming techniques for interaction design, showing programmers how they can make creative contributions to device design.”

Get more details of Press On from the book’s web site.

Awards picture

Choice Outstanding Academic Title, 2008

Choice is the Association of College & Research Libraries, a division of the American Library Association and is the premier source for reviews of academic books, electronic media, and Internet resources of interest to those in higher education; unfortunately you need to register to see details.

9. Swansea & the Gower

Rhossili bay
Rhossili bay

Swansea is right next to the sea, near to the Gower Peninsula, Britain’s first — and finest — area of outstanding natural beauty.

Three Cliffs bay Swansea beach, looking towards the city
Three Cliffs bay
5km from university
Swansea Bay, looking towards the city
100m from university
View of sea from my office
View of Swansea Bay from my office
Looking towards Mumbles and Devon
View of my office from my home
View of my office (the block in the middle)
from my home, on a snowy day

10. Do research with Harold

The building where we work
The building where we work

If you are interested in doing a PhD (or any other research, such as European Marie Marie Skłodowska-Curie Fellowship) with Harold, please contact me direct; we get zillions of applications, so the best thing to do is engage, visit, and meet us so that we know more about you.

Don’t fill in the University application form first and just wait for things to happen somehow automatically, as perhaps you’ll get lost in the noise!

If you want to do a PhD, you need to find a supervisor who you’ll will be able to enjoy working with for three or four years — and possibly much longer if you follow a research career and carry on collaborating. Find out a bit about potential supervisors (me or my colleagues) and send them crafted emails they will want to read.

I get many spam emails (i.e., that appear to be sent to nobody in particular) from people who want to do their own PhD project, but while this shows you are interested in something (and perhaps how deeply you have thought about it), it shows you aren’t interested in who you will work with.

In reality, you negotiate a project: what can be funded? what is interesting research? what will get a PhD for you? what will work with the team at Swansea? what will Harold be interested in? So, if you are going to email me, make sure I can tell the difference between your email and spam! “Hey Harold, I read your paper … and I want to work with you!” — or something. Also, please send me your CV and any details about funding you have or need — it costs money to live and do a PhD, and that has to be sorted out up front!

If you are at all interested in a research career anywhere — whether as a PhD or as an RA, or even as a PDRF (postdoc) — you should have a good look at Vitae.

Currently, Harold has had excellent postdocs, RAs, PhD researchers, and others:

See also SURF, the Swansea University Research Forum, which Harold founded.

11. Examples of research

A hands-on gadget Harold made for explaining cryptography
Working Enigma machine
Harold made for explaining cryptography

Conventional design is often a mix of creativity and evaluation, missing out analytic thinking. This often results in nice-looking systems with problems for their users. Much of Harold’s work has been in working out methods to improve the early stages of design, particularly based on programming, maths or computer science.

Harold has developed many powerful and practical results based on fully working programs and mathematical methods — he is an excellent programmer.

Harold has worked in algorithms, artificial life, autostereograms, computer ethics, computer viruses, digital libraries, human-computer interaction, mobile computing, software engineering and the public understanding of science. Harold is particularly interested in research itself, particularly with the rapid expansion of computer science.

Older things

12. Funded projects @ Swansea

Drug dose calculator
Drug dose calculator

See EPSRC grants on the web for all Thimbleby’s EPSRC funded projects. (This list doesn’t include travel grants, Fellowships, etc)

TitleRoleEPSRC referencefEC value
Formally-based tools for user interface analysis and designPIEP/F020031£711,273.39
FIT Lab/UCLIC PLATFORM: Healthy interactive systems: Resilient, Usable and Appropriate Systems in HealthcarePIEP/G003971£431,076.07
CHI+MED: Multidisciplinary Computer-Human Interaction research for the design and safe use of interactive medical devicescoIEP/G059063£6,772,571.07
Swansea University :: Bringing People TogetherPIEP/I00145X£965,708.17
Point of care nanotechnology for early blood clot detection and characterisation in disease screening, theranostic and self monitoring applicationscoIEP/G061882£1,078,563.32
The Global Hub in Medical Technologies and NanoHealth at Swansea UniversitycoIEP/K004549£493,092.89
Impact accelerationcoIEP/K504002£637,927.00
Discipline Hopping into HealthcarePIEP/L019272£96,681.00
The CHERISH-DE Centre — Challenging Human Environments and Research Impact for a Sustainable and Healthy Digital EconomycoIEP/M022722£3,091,610.00

13. Teaching

Mobile phones pinned in a butterfly display case
© H Thimbleby, Tippingpoint, Berlin, 2008
Click to see larger image

Seven steps to success?

  1. Get the generic lecture notes for any module (PDF) — and print them off and use them!
  2. How to use the lecture notes — instructions for first-timer
  3. Write your coursework and hand it in (PDF) — advice to writers
  4. Read my book — if you’re doing a course that needs it
  5. Read other things, keep up to date, do things, and … start here!
  6. How to give great presentations (or what to think about during dull presentations)
  7. Some ideas for projects (though far better to talk to me)

If you are a lecturer or a student who wants to engage with their lecturer, please read Making teaching come alive

And if you want coursework resources for CSM19 (Interactive systems design), click here!

14. Fun and trivia

Trivial Pursuits
Trivial Pursuits

Apple MacBook Pro 15"

My new Apple MacBook Pro 15" laptop keyboard, 9 days out of warranty — it was not out of warranty when it first had the fault, but to diary an appointment at an Apple Store took me just beyond the warranty period.

It has always had a poor keyboard ever since new, and finally one key stopped working altogether, rather than just being unreliable. I made a special trip to Apple, who fixed it. It broke again the next week. Another trip, and Apple repaired it, but this time wanted £481.80. (Actually, £332.50 plus labour plus VAT.)

It’s hard to imagine, for a long-established company, that this isn’t a clever strategy for making money: make an unreliable keyboard (the Apple Store said it was!) and design it so that the keyboard ‘has’ to be replaced along with the entire top of the laptop. Then you can make £481.80 for repairing one key.

I had been thinking of writing a review of USB-C and minidisplay port confusions, and charging confusion, but the key cap failure trumps it.

Genailles Rods

Front cover of Mathematica Journal based on my program for Genaille’s rods, a fun type of calculator. Henri Genaille’s Rods are a nineteenth-century scheme for doing multiplication, similar to, but easier to use than, the more familiar Napier’s Bones — as you can see, Genaille’s Rods are visually attractive. They are useful in teaching. My article gives full details.

Clear presentation, recursive programming, and art are all irresistible — here is a clear visualisation of the deaths on the Titanic that also makes a nice Mondrian-style painting. — click this link to find out more!

Harold in Trivial Pursuit

Here’s my name on a card from a Trivial Pursuits game. Mouse over the card to see the answers!

Based on analysis of use of Jonathon Fletcher’s JumpStation, the world’s first web search engine, in fact I said most internet searches were for porn — perhaps not so surprising given the demographic of surfers in those days!

For a more substantial discussion about the internet see my Personal boundaries/global stage article for the IEE 2020 Visions conference, now published in First Monday.

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