Why designers can't understand their users, book

developing a systematic approach using cognitive psychology

Dr. Leonard Verhoef

222 pages, 38 euro, third edition, ISBN: 9789080997516.
DOI: 10.13140/RG.2.1.1797.8483
Order the book



The first question elaborated in Part I is: How is it possible that we have programmable, interactive, multi-media, world wide communicating computers, that are not capable of communicating with their master.

To answer this question, first applied cognitive psychology is analysed. This science should know how to design user-friendly computers.

  One approach applied cognitive psychology uses is an elementary approach focussing on isolated practical questions that easily can be answered using fundamental psychophysiological knowledge (What character size, what colour or what luminance to use?). This knowledge makes screens readable and buttons ‘press-able’. However, computers remain incomprehensible. Knowledge on how humans think is needed for comprehensible computers. Several students pointed out that a holistic approach is needed taking account of elementary knowledge together. Applied cognitive psychology does not straightforwardly state how the combination of elements of a design should be dealt with. The effects of size, colour and luminance is known. Not known, for instance, is which one of these three is the best to present a new entry in an alphabetical list. For cognitive problems, such as how to arrange trains on an indicator or options of a menu, applied cognitive psychology provides designers with little help. Many researchers flight for that problem in using scientific knowledge to answer questions dictated by practice and technology (“Where to position the OK button?” and “What is the best depth and breadth of a menu?”). With scientific methodology they plant a scientific flag on a non-scientific, practical and technological load. Today the result of that approach is clear, computers still are userunfriendly and there is no general accepted foundation of applied cognitive psychology. This book elaborates and tests a Solution having the following characteristics. The questions to investigate do not follow from practice and technology but are dictated by science and psychology. Subject of study is not the interface technology itself, such as the menu or the touch screen, but the properties of that technology that are relevant to obtain insight in the way users think when performing a task with a computer. The load under the flag is not a practical or a technological problem but a synthesis of the relevant psychological knowledge needed to arrive at userfriendlyness. This psychological synthetic properties approach leads for practice to userfriendly designs and for science to fundamental knowledge needed to understand how users work with computers. In common language: not ‘more research is needed’ but ‘no further research is needed’, science has found the truth.
  The second question discussed in Part II is: What Solution will make computers user-friendly?
The basis is the common Man Computer separation.


‘Man’ is specified in the Solution of this book as a system performing motor, perceptual, language, memory and thinking actions, for instance with a computer. Hands are typing or pointing, eyes focus on a screen reading icons or words that are associated in human memory and should help human thinking to perform a task. This specification seems obvious, however, in design practice, design literature and applied cognitive psychology it is not a common one.

Usually the computer is specified as the interface technology applied. The focus is on interface technologies, such as menu’s, form filling, command language input and voice input. This book concludes that this interface technology approach cannot give insight in how humans think when working with computers. The book’s Solution is a properties approach. An interface is divided into properties having a direct link with the characteristics of psychological processes (movement, perception, language, learning and thinking).The properties of the elements of an interface can easily be defined using the elementary approach (e.g. size, form and contrast). Finding the properties for combinations of elements is more difficult. The book suggests three field properties: quantity, distance and structure. For all five function fields (movement, perception, language, memory, and thinking) the same three field properties apply.

  The third question in Part III is: Does the Solution deliver user-friendly computers?

Four properties are used to find an experimental answer on that question (visual size, visual distance, cognitive quantity and cognitive structure). The tasks investigated are simple every day tasks like finding a station on a ticket vending machine, noticing that a vending machine is out of order and finding a train in a list of trains on a dynamic trains indicator.
  The first experiment, reported in chapter 8, is an easy one. The element property: visual size that is used to improve the userfriendlyness of finding a station in an alphabetical list. It is supposed that different properties for a new entry have a different effect on search time. European Railway companies used several lay outs such as an empty button with the letter ‘A’ above all stations starting with the letter ‘A’. The Solution provides a list of all basic lay outs. The Solution suggested using visual size to indicate a new letter in an alphabetic list. The answer on the third question proved to be that the Solution produces a more user-friendly list of stations than did the common design strategy.

The conclusion proved to be generalizable. There was no need for research when ticket vending machine technology changes from a ‘one station – one button’ interface to system requiring the entry of a ‘numerical code’ for a station and when touch screen technology was introduced. The knowledge also is applicable in other domains such as lists presented on computer screens.

Chapter 9 analyses a visual field property, ‘visual distance’ used to improve userfriendliness of two tasks: “Notice a vending machine is out of order” and “Notice instructions on ‘how to insert a banknote’.”

When visual distance is large, 6.4% of users does not notice the machine is out of order, and when visual distance is small 1.9% presses a button on the machine that is out of order.

The text ‘how to insert a banknote’ is noticed by 69% of the users. When visual distance is reduced this figure is 78%.
Both experiments give a positive answer on the third question. The Solution suggests a more user-friendly position the positions used in common designs. The conclusions on visual distance proved to be generalizable. When ticket vending machine technology changes from pressing a button with the name of the station, to entering a numerical code of the station, visual distance between station name and code is kept as low as possible. Station name and code are separated by one space only and not spaced by a tab, as usual. When ticket vending machine technology changes again, from a button interface to a touch screen interface, no new experiments are needed. The knowledge on visual distance was used to improve userfriendliness of the new touch screen train ticket vending machine and a coffee vending machine.

  Chapter 10 analyses cognitive quantity to improve the user friendliness of finding a departing train on a trains indicator. An observational experiment in Amsterdam Central Station revealed that only 62% is able to find the best train. Deleting less relevant trains makes 3% more passengers find the best train and reduces mean travel time wit 1.2 minutes. So the answer on the third question is: yes, the Solution leads to more userfriendliness than the common design.

The conclusion proves to be generalizable to ticket vending machines where a better ticket type design is suggested, having less decisions to make per button press (on button ‘coffee with milk’ or two buttons, one for coffee and one for milk.
The final experiment in chapter 11 focuses on using cognitive structure, again for the task of finding a departing train on a trains indicator. Another suggestion of the Solution is that cognitive structure of the information causes the poor performance of the passengers in the observational experiment.

In an experiment the common trains indicator is compared with an uncommon destination indicator suggested by the Solution. The number of correct selections, the mean delay, the mean search time and the passenger evaluation are substantially better for the uncommon destinations indicator suggested by the Solution. Again a positive answer for the third question: the property approach delivers user-friendly trains indicators.

The conclusion proves to be generalizable to other interface technologies (screen technology), to route strips presenting the stops of a train, time table books and computer program menu’s, which, as can be seen on any computer mostly are of a type the Solution identifies as ‘chaotic’.

  Scientific experiments should provide definitive answers to the question posed. Scientific practice shows that, nevertheless, there often is discussion on answers based on experiments. Therefore the fourth question in Part IV of this book is: “Is the Solution really better?

This book applies the Solution to the way travel information should be arranged enabling passengers to perform their tasks efficiently. The Solution easily is generalised to other interface domains such as screen vending machines, coffee vending machines, time table books and signposting and to other interface technologies such as computer screens. Theoretically, the Solution should be generalizable to the way information for designers should be arranged enabling them to design user-friendly machines. Both, passengers and designers, use the same psychological processes. The book accepts this challenge and tests the Solution, on the application of psychological knowledge for designers given by three solutions found in literature. The Solution suggests that these competing approaches arrange the information for designers in a chaotic way. Finally a last challenge for testing the Solution is, testing the Solution itself with the Solution. What is the opinion of the Solution on the Solution itself?
  What are the results of this book? Of course, userfriendliness is no issue. But there is more in this book.
Designing a userfriendly machines seems to be the same as designing a cognitive psychological theory on designing. There is a solution that is capable of testing itself. Foresight of the Solution leads to uncommon design that, after being designed, with backsight are evaluated as the common ones. Not the usual 'more research is needed' but an unusual 'no more research is needed' is the conclusion.
  The Epilogue tries to come back to the title question of this book: “Why designers can’t understand their users”. So far the smoke screen of ‘science’ has been effective in not blaming psychology for one of today’s major commonly accepted mysteries: computers incapable of communicating with their master. This book foresees that when time has blown away the smoke screen of science, our grandchildren having backsight can’t understand why we accepted today’s mystery of userunfriendlyness and that they might blame today’s cognitive psychology.
To top.


Part I




Part II









The Problem:
how to apply fundamental experimental psychological knowledge

From psychology to practice

Maintaining a scientific approach in practice

Which approach to apply

Elementary approach
Holistic approach
Synthetic approach

The Solution:
a synthesis of psychological and design concepts

The 'man' component

The 'interface' component

Interface technology approach
Practical and experimental problems
Theoretical problems
Properties approach
Properties of the element of an interface
The value of properties of elements
The field properties of an interface
Which field properties of the interface
- The field property quantity
- The field property distance
- The field property structure
‘Man’ and ‘Interface’

The 'task' component

Testing the Solution

Theoretical evaluation
Empirical test using students
Practical test by comparing designs
How the synthetic model will be tested
Part III








better designs with the Solution?

Visual size

What is visual size?
Why visual size?
Which sizes?
Experiment: the effect of size on visual search performance
Generalisation of knowledge
Interface technology generalisation: numerical code train ticket vending machines
Interface technology generalisation: screen train ticket vending machines
Domain generalisation: lists in computer interfaces

Visual distance
What is distance
Distance in other function fields
What is visual distance?
Why the term visual distance
Which visual distances
Experiment 1: comparison “Out of order”
Experiment 2: comparison “Insert this way”
Generalization of knowledge
Interface technology independence: 360-destinations vending machine
Interface technology independence: touch-screen vending machine
Domain independence: a coffee vending machine









Cognitive quantity
What is cognitive quantity
Why cognitive quantity
Which cognitive quantities
Experiment 1: observation of performance
Experiment 2: the effect of cognitive quantity
- The indicator used
- Condition little information; single indicator
- Condition large amount of information; double indicator
- Scoring
Generalization of knowledge
Interface technology generalisation: button train ticket vending machine
Domain generalisation: the Windows Office terminology

Cognitive structure

What is cognitive structure?
Structure in other function fields
Why cognitive structure?
Structure and literature
Structure and design
Which cognitive structures?
Experiment 1: observation of knowledge of the structure
Experiment 2: comparison of structures
Generalisation of knowledge
Interface technology generalisation 1: train indicator
Interface technology generalisation 2: timetable books
Domain generalisation: computer program menus
Part IV











Part IV Testing the Solution:
is the Solution really better?

Testing the Solution, using literature
Testing the human component
Testing the system component
A web-based usability handbook
A foundation of knowledge

Testing the Solution, using the Solution

Is the human component nominal?
Is the human component ordinal?
Is the system component nominal?
Is the system component ordinal?
The structure of the system components


Conservative domain
Why bother, use new technology
The results and conclusions are obvious and not new
The truth
Finding the truth with fora
Finding the truth with experiments
Finding the truth with history
The truth found?

Design indicator experiments
Search time
Passenger evaluation

Random list with destinations
Table of contents: Software psychology

Table of contents: Designing the user interface

Structure of: A web-based handbook

Table of contents: Encyclopaedia of Ergonomics and Human Factors

To top.


In the beginnings of ergonomics, in the early years of the Twentieth Century, pioneers such as Taylor started to design work, and the tools that people had to use, in systematic ways. Taylor’s major study began in 1898 at the Bethlehem Steel Co. with his study of how labourers handled pig iron (Fraser, 1951). Using a combination of common sense and the rigorous application of a systematic methodology this approach, then called ‘Taylorism’, made it possible to effect substantial improvements in human efficiency. However Taylor’s approach, using his notion of Time and Motion measurement, made no use of insights about the human body that would have to perform the work being optimised nor any understanding of the mental functions that allowed the work to be performed. Jobs were optimised by measuring what happened and by reducing redundancy and inefficiencies to a minimum. What knowledge there was can best be described as common sense, admittedly a commodity that has never been in surplus. A next great step to the improvements to human efficiency in the workplace was made by fitting work and tools to the human body. Initially the focus was on human bones and muscles, the ‘hardware’ of the human being. Knowledge of human psychophysiological characteristics followed later, adding understanding about more mental functions that could be applied to the increasing improvement in supporting human working conditions and increasing productivity. At that time systematic knowledge, as had been collected and used in medicine and the (physical) psychological sciences, provided sufficient basic information for use in the design for better chairs, improved lighting and increased readability of texts. The application of medical and physiological knowledge to the design for tools and the work situation was presented in handbooks for human factors and ergonomics. The two best known examples of this genre are Grandjean’s (1963) ‘Physiologische Arbeitgestaltung’ (Physiological work design) in Europe and McCormick’s (1964) ‘Human factors engineering’ in the United States.
  Two decades later Grandjean published an updated version of his first book under the title ‘Fitting the task to the man’ (Grandjean, 1980). The title of this book reflects the spirit of that time. The focus had started to change from placing primary attention on the physical structure of the human body and the design for physical tools, to a more abstract interest in the tasks to be performed and the tools designed to support performance of those tasks. However, the contents of that revised book reflect the inability of ergonomics as a discipline to make the transition necessary to deal successfully with more abstract and complex tools, such as the computers that were by then making their inroads into daily life and with the mental cognitive tasks that users wanted to, and now could perform, using those computers. Medical and physiological themes continued to dominate the book. The word ‘task’ was found in the title of the book, but nowhere in the index nor even in the title of any of the chapters. The book does now have a chapter on ‘Mental activity’; however, that chapter discusses much more basic physiological aspects such as channel capacity and vigilance. Concepts involving higher mental functions, like decision-making, problem solving, conceptual structure, navigation and orientation cannot be found anywhere.

  Although many practicing ergonomists and technicians did the best they could, the available practical, medical and physiological ergonomic knowledge did not provide information to allow them to design comprehensible interfaces. They lacked a body of knowledge and an applicable understanding of the mental processes to design interfaces for human users that would be effective and fit for purpose without considerable hands-on design and field-testing. The design process was still based more on the, hopefully, successful application of common sense by the designer than on any well articulated body of knowledge about human users and their capabilities. Research was often reduced to the comparison of alternatives supplied by the technology available, with simple measures of task performance determining which design ‘won’. That kind of comparative research does not provide basic and generalizable knowledge ergonomists can use in the practice of everyday design. Technology was free to dictate the interface in ways convenient to the technologist, and human users were usually expected to adapt to the technology rather than vice versa. The norms, standards and requirements that ergonomists produced for the design of user-friendly computers are, consequently, haphazard lists of vague concepts (note 1) that cannot be related to fundamental psychological processes, at least not in any straightforward way. ‘Real’ ergonomics still involved giving useful advice about reachability, visibility under reduced lighting conditions and physical comfort for human users rather than dictating designers how to construct devices that people can use effectively in their everyday life. That was the situation when I started my career as a graduate experimental psychologist.
Note 1
Some of these concepts are:
aesthetics (Microsoft 1995l); clarity (Preece 1994l); consistency (Microsoft 1995l; Preece 1994l; Shneiderman 1993l; Mandel 1997l); controllability (Den Buurman et al. 1985;l Mandel 1997l); directness (Microsoft 1995l); engineer for errors (Preece 1994l); feedback (Microsoft 1995l); forgiveness (Microsoft 1995l); integration (Shneiderman 1993l); intuitive; know the user (Preece 1994l); look and feel; pleasureability (Norman 1998l); portability, (Shneiderman 1993l); reduce cognitive load (Preece 1994l); reduce memory load (Mandel 1997l); robustness (Den Buurman et al. 1985l); self explaining (Weeda, in Voskamp, 1996l); simplicity (Microsoft 1995l; Norman 1998l); standardization (Shneiderman 1993l); symry (Den Buurman et al., 1985l); tolerance for error (Weeda, in Voskamp 1996l); transparency; usability (Landauer 1995l); user centered design (Norman 1998l; Landauer 1995l); user comfort; user expectance (Weeda, in Voskamp 1996); usefulness (Landauer 1995l); user in control (Microsoft 1995l); user-friendly; versatility (Norman 1998l).
  The situation today is that we have increasingly rapid computers having a larger and more stable memory than humans. These computers are interactive and multimedia, they are able to present and accept information in visual, auditory and even tactile ways, they can easily communicate with any other computer in the world, but they can still not communicate effectively with their masters. People can now be seated comfortably before their computers, can avoid RSI if they follow the simplest of guidelines and use ergonomically designed keyboards etc, but they still fail to understand what their computer is doing or how to make it do what they want. Much has been written on the causes of this interface problem. Norman (1990l, 1998l), for instance, has blamed technology. Cooper blames management (1999l). So far, nobody has pointed the finger at psychology. It is an intriguing question; how is it possible that on the one hand there is an interface problem, whereas on the other hand, the common computer interfaces used today are in conflict with psychological knowledge that has been available for several decades? Fortunately I have been involved in several design projects in which I did not need to accept interfaces dictated primarily by technology and as a result, had to compromise experimental psychological knowledge and methods. All too often psychological knowledge is used in hindsight to explain why an interface works, or fails to, and if the technology requires it, then the psychological demands take a second place, with the argument that people are very adaptable.
  In several of the projects that I was involved in, I have been fortunate that management understood that psychology should dictate technology and (graphical) design. They did not want to be driven by the psychological prejudices of technicians, designers, the opinions of users or even their own common sense psychology. They were professional managers who dared to strike out on an unusual but effective road. They gave me the opportunity to develop, to investigate and to design using experimental psychological knowledge.
Some of these projects are:
  • Train ticket vending machines for Netherlands Railways, reported in several chapters of this book. For a demo Google: "NS demo treinkaartautomaat" Dutch and English.
  • ETCS, European Train Control System for European Rail Research Institute. See Etcs-mmi background www.rks.nl/designprijs/97 /19.html.
  • Coffee vending machine for Van Nelle, presented in Chapter 9.
Schön (1983) observed that ‘systems of knowing-in-practice may limit the scope and depth of reflection.’ This book presents the story of how I applied fundamental experimental psychological knowledge to interface design without compromising psychology. In doing so I have attempted to understand how I arrived at designs that worked and reflected on what was necessary to achieve that result in order to distil principles that have considerable generalizable power. In a sense the theory is developed by the test in practice, in contrast to more common methodologies where the practice tests the theory. Nevertheless the cycle of theory and empirical test is still identifiable; even in practice, experimental psychologists can still ply their trade. Looking backward it was a simple, short and interesting voyage taking me over the borders of today’s concept of psychology, science and methodology. This report of the voyage proved to be not simple and short but complex and long. Part I ‘The Problem’ shows that common vehicles for this trip provide little help. The way scientists and professionals are currently trying to improve interface design is not the right way, or certainly not a useful one. Part II ‘The Solution’ describes the vehicle built for this journey. How have interfaces been improved in this book? The four principles of the Solution I used to apply to design are described in Part III ‘Experiments’. The first, ‘visual size’, is a quite simple one intended mainly to get used to the Solution used in this book. The last one ‘cognitive structure’ is, in my opinion, the most interesting one as it might show a new way of looking at the world of designing.
  An analysis of that principle is made in Part IV ‘Testing the Solution’ by comparing it with approaches from the old world of interface design. Is this way of looking new? Is it magic? Is it science? Is it applied? Is it engineering? Or is it merely common sense? An intriguing problem in doing this research emerged. A frequently given comment on the redesigns investigated is: ‘Of course, the redesign is better. Why did you do the experiment at all?’ These commentators neglect common design practice and seem to have forgotten the introduction of the experiment describing common designs in which the psychological principles tested are applied the other way around. After having read the book carefully, taking into account common design practice and discussed the content, what will be the outcome? Will there be cognitive chaos which is inherently to the acquisition of new knowledge? If so, will that chaos be in the mind of applied cognitive psychologists, designers or in the mind of the author?
To top.

Pictures and quiz:

How to present departure times?
Scientific questions in common language. Common designs and uncommon but psychology based designs compared.

What are the differences between the two indicators?
Which arrangement gives shortest search times?
How many minutes will travel time per passenger decrease, when using the best arrangement?
Why is this arrangement cheaper?
Which one is the most commonly used?
trains indicator schedule board of Amsterdam Central Station. trains indicator schedule board of Amsterdam Central Station, destinations
To top.

Pictures and quiz:

A routestrip on a platform how to arrange stations?
Which arrangement is most common?
Which arrangement is best on platforms?
The other arrangement is appropriate for ...?
Two routestrips in some London Underground station.
To top.

Pictures and quiz:

How to design lists?
There are several ways to indicate a search entry in a list, for instance, a list of stations on a train ticket vending machine.
Which presentation allows shortest search times?
Which presentation is cheapest?
Which presentation is the best choice?

formatting entries in listsformatting entries in lists, character size

. formatting entries in lists, largest character formatting entries in lists, (Switzerland).
To top.

Pictures and quiz:

How to present 'Insert this way'?
What is the best position to inform users on how to insert a bank note or bank card?
Which of the presentations below wil give the largest number of correct insertions?

How to insert: above slotinsertion of bank notes and cards in slots of machines,

insertion of bank notes and cards in slots of machines insertion of bank notes and cards in slots of machines
To top.

Pictures and quiz:

How to select?
What is better:
One button more questions?
One button one question?
The answer is in the article: Decision making of vending machine users
Three buttons: one for class, one or yest/no reduced price, one for single/return. Three buttons: one for class, one for yes/no reduces price, one for single/return.

One button for: class, reduced price and single/return One button for: single/return and 1st/2nd class.
To top.

More practical stuff for designers

Less focus on a scientific basis and more focus on practice (470 examples); not only two visual properties and two cognitive properties but all properties and movement, language and memory as well, in the books: GUI, webontwerp, psychologie en human efficiency 1 en 2 (in Dutch, however). In the seminar 'GUI, webdesign, psychology and human efficiency' you can see psychology in action with your own interfaces and opinions on interface design. There is more on that course in English and in Dutch. This course can also be presented in German and French.
To top.

Order the book "Why designers can't understand their users"

Price: € 38 (including 6 percent vat). Order per email. Confirmation of order per email.
 The NetherlandsEuropeOutside Europe 
Book€ 35,85€ 35,85€ 35,85
Shipping€ 3,30€ 6,60€ 9,90 per order
Vat 6%€ 2,35€ 2,55€ 0,00
Total€ 41,50€ 45,00€ 45,75

To top.
1 day, most cases,>5 days,  >8 days most cases.
To top.
Nederlandse tekst


Utrecht, 1 september 2007

Waarom zijn computers toch zo moeilijk te bedienen?
Het is zo gemakkelijk een eenvoudige computer te maken

Op 19 september 2007 verwacht drs. L. Verhoef te promoveren tot doctor in de sociale wetenschappen met Why designers can't understand their users".
Dit boek is het resultaat van jarenlang onderzoek naar en ontwerpervaring met de alledaagse problemen die computergebruikers hebben met de programma's waarmee ze moeten werken. Verhoef analyseert de problemen en komt vanuit de psychologische functieleer met onconventionele en verrassende oplossingen die aansluiten bij de werking van de menselijke geest.
Verder onderzoek is overbodig
Gebruiksvriendelijk, experience, beleven, intuïtie, look en feel: het zijn psychologische begrippen die ontwerpers van computerprogramma's gebruiken zonder echter een psychologische basis. Ze komen daarmee weg omdat de menselijk geest zo immens flexibel is en zoveel kan leren dat hij zich vroeg of laat wel aanpast aan hun bouwsels. Het onderzoek van Leonard Verhoef
toont bovendien aan dat de common sense oftewel gezond verstand-psychologie er vaak naast zit.
Het boek spitst zich toe op reizigers die een treinkaartjesautomaat gebruiken en die op elektronische borden kijken om te zien hoe laat hun trein vertrekt. Het inventariseert de taken van de gebruikers: het zoeken van een station in een lijst, zien dat een automaat buiten dienst is, het invoeren van een bankbiljet of pas, het zoeken van de vertrektijd van een trein of een bestemming op een elektronisch bord.
Allemaal drie minuten eerder thuis
Verhoef analyseert en verklaart met simpele functiepsychologische kennis de fouten en misverstanden die optreden. Hij geeft aan hoe het wel moet en toont de testresultaten van een alternatief. Het alternatief is niet alleen veel 'gebruiksvriendelijker' maar blijkt vaak tientallen procenten goedkoper te zijn en brengt de reiziger bijvoorbeeld gemiddeld drie minuten eerder thuis.
Verder laat hij zien dat dezelfde benadering werkt bij spoorboekjes, koffieautomaten, bewegwijzering, de mappen op een scherm van Windows, het hoofdmenu van Word en zelfs zijn eigen boek. Verder onderzoek is wat hem betreft overbodig.
"Why designers can't understand their users" geeft oplossingen vanuit de functiepsychologie voor veel dagelijkse bedieningsproblemen. De meeste daarvan zijn haast te simpel voor woorden, als ze eenmaal gevonden zijn. Bezien vanuit de functiepsychologische invalshoek bieden ze zich vanzelf aan.
Verhoef was onder andere nauw betrokken bij het ontwerp van de verschillende generaties treinkaartjesautomaten van de NS en het Europese systeem voor het veilig laten rijden van hogesnelheidstreinen (ETCS). Momenteel concretiseert hij hoe ons dagelijks leven er in de toekomst uit zal zien, als de bediening van apparatuur voor niemand hoofdbrekens kost.

Review: Maas-Maarten Zeeman Read a really nice usability book. It uses cognitive psychology as an elementary approach to design user-friendly apps.
To top.
Review: Peter Simlinger

Information Design Journal, Vol. 17, no 2, pag. 159-160

Logo: IIID
International Institute for Information Design (IIID), Wien/Vienna, Austria
Despite the fact that Leonard Verhoef confuses design with technology and vice versa, his book opens a window on what cognitive psychology could mean to information designers. The provocative title of the book remains unclear until the last paragraph on page 170: One can blame management as Cooper does (1999). So far this smoke screen of science has been effective in not blaming psychology for the interface problem. When time has blown away this smoke screen, Im afraid our grandchildren may well blame todays psychology for designers not understanding their users.To demonstrate the alternative indicated in the subtitle of the book Developing a systematic approach using cognitive psychology Leonard Verhoef shows how to find fundamental (psychological) concepts for interface design and then how to arrange these concepts in a way that allows both an elementary and a holistic approach. On page 157 he says: The fundamental concepts should be generalizable i.e. time, domain and interface technology independent. At the same time, the fundamental concepts should allow reliable prediction on human performance of any time, any interface technology and any domain … including applied cognitive psychology itself This sounds pretty sympathetic to me.
To top.
  Referring to research done in the field, Leonard Verhoef blames his discipline for not having provided basic and generalizable knowledge ergonomists can use in the practice of everyday design (p. 8). Turning the tables on his discipline and supporting this with concepts based on his own research, Leonard Verhoef presents himself as a designer with a psychological background, rather then as a psychologist. Considering that all his research on the interface(s) of ticket machines and timetables is easily transferable to interfaces of all sorts of other machines, e.g. such for making coffee, his insights lead up to concrete design solutions, Leonard Verhoef should be whole-heartedly welcomed as a member of the design community.What has Leonard Verhoef offered to designers and those in his ancestroral trade? He clearly distinguishes between an elementary and a holistic approach which, according to his deliberations, need to be brought together in a synthetic approach. In Part II The Solution (a synthesis of psychological and design concepts) Verhoef argues that the Man and system components need to complement a Task component which is to include goal or the aim of human activities. This very much reminds me of the persona that Alan Cooper proposes, that can be used to replace target groups with exemplary users.
  As Verhoef says (page 49 of his book), when evaluating components (human, system, task), a property approach to interface design (in which technology is adapted to humans and not vice versa) is preferable. Doing it the other way round would mean swapping master and slave.Subsequently, Verhoef introduces the properties of visual size, visual distance, cognitive number (quantity) and cognitive structure. The explanation of visual  distance and the need to keep is as short as possible impressed me most. It requires presenting information at point zero for the user as distinct from a fixed position, e.g. in a menu at the top of the screen.
  Verhoef also gives examples of other functions in which distance plays an important role. He refers to near and far away buttons, which require finger movements and wrist or arm movements, information within and beyond a fixation area, short and long term memory and the fact that greater conceptual distance requires more effort to strive after meaning. Interesting parallels to Hermann Knoflacher's theory that the degree of physical effort involved in traveling a given distance determines the choice of transport modes (see the article Infoconnectivity – The value of certainty and uncertainty for interconnected transport networks).To keep this review short, I should not engage in elaborating other properties nor refer to the many experiments which underpins Verhoef's concepts of a systematic approach using cognitive psychology to attain design solutions.

Those of the readers with an interest in theory and method, as well as those with an immediate concern in interfaces of vending machines, timetables and train departure indicators are strongly advised to engage in a critical appraisal of Leonard Verhoef’s book.
To top.


Nederlandse tekst
Alles kan slimmer, Bart Braun, Dutch PROMOTIE - Mare 04, 27 september 2007,

Ontwerpen zonder menu, Jorge Groen, Dutch Computable 40| 5 oktober 2007

Gebruikersvriendelijke computers, Noorderlicht di 18-09-2007 10:03, Dutch

De psychologie achter informatieborden, OV-Magazine 30 augustus 2007 Dutch http://www.ovmagazine.nl/Laatstenummer/tabid/236/articleType/ArchiveView/month/

(On)handige apparaten, Teleac radio, Hoe? Zo!, maandag 15 oktober 2007, 23:00:00http://www.teleac.nl/radio/index.jsp?site=site_radio&category=1683626&nr=134903&item=1443783&template=%2Fradio%2Ftemplates%2Farticle_weblog.jsp

Ontwerpen zonder menu, Jorge Groen, Dutch Computable 40| 5 oktober 2007

Trends in IT, Wat wil de gebruiker? Thema nummer Dutch Design 2008, nr1, feb, vol. 17.http://www.exin.nl/Nieuws/Magazine/~/media/
To top.
Nederlandse tekst


Dit boek onderzoekt waarom computers gebruiksonvriendelijk zijn en hoe men gebruiksvriendelijke computers kan maken.

De eerste vraag is: "Hoe kan het toch dat er programmeerbare, interactieve en multimediale computers zijn, die met alle andere computers in de wereld kunnen communiceren maar die niet kunnen communiceren met hun baas, de gebruiker."

Om een antwoord te vinden op deze vraag analyseert Deel I “Het probleem”, de toegepaste cognitieve psychologie. Deze wetenschap zou moeten weten hoe je gebruiksvriendelijke computers moet maken.

Een oplossing die de toegepaste cognitieve psychologie voorstelt is een benadering vanuit de elementen. Daarbij richt men zich op geisoleerde praktische vragen waarop men met psychologische methoden eenvoudig een antwoord kan vinden. (Welke afmeting, kleur en helderheid kan men het beste kiezen?). Met deze kennis kan men informatie op schermen leesbaar maken en men kan toetsen zo ontwerpen dat de gebruiker deze snel en zonder al te veel fouten kan indrukken. Kennis over de wijze waarop mensen denken is noodzakelijk.

Vooraanstaande ergonomen hebben erop gewezen dat een benadering vanuit het geheel nodig is waarin de kennis van de afzonderlijke elementen geïntegreerd is. De toegepaste cognitieve psychologie geeft niet duidelijk aan hoe men deze kennis moet integreren. De effecten van afmeting, kleur en helderheid op de menselijke prestaties zijn bekend. Niet bekend is bijvoorbeeld welke van deze drie men het beste kan gebruiken om aan te geven dat er een nieuwe letter begint in een alfabetische lijst.
  De toegepaste cognitieve psychologie geeft weinig aanwijzingen voor de wijze waarop men problemen moet oplossen waarbij mensen vooral hun verstand moeten gebruiken, zoals  de volgorde van treinen op een vertrekoverzicht op het station en de opties van een menu waar een computergebruiker uit moet kiezen. Psychologen kunnen deze lastige vragen gemakkelijk ontwijken door hun wetenschappelijke methoden te gebruiken om vragen te beantwoorden die gesteld worden door de praktijk en de techniek, zoals ‘Waar moet de OK button staan?’ en ‘Moet een menu veel opties in het hoofdmenu hebben en weinig in het submenu of juist omgekeerd?’ Met de wetenschappelijke methodologie planten zij een wetenschappelijke vlag op een niet-wetenschappelijke, praktische en technologische lading. Het resultaat is duidelijk. Computers zijn nog steeds gebruiksonvriendelijk.

De Oplossing die dit proefschrift uitwerkt heeft de volgende kenmerken. De Oplossing gaat niet in eerste instantie uit van vragen die gesteld worden door de praktijk of de techniek maar gaat uit van vragen die men wetenschappelijk gezien eerst moet stellen. De oplossing richt zich niet op de interface techniek zelf, zoals het menu en het aanraakscherm maar op de eigenschappen van die techniek voorzover deze eigenschappen de prestaties van mensen met die techniek bepalen. De lading onder de vlag is daardoor niet een praktisch of technologisch probleem maar een synthese van de psychologische kennis die leidt tot gebruiksvriendelijkheid. Deze synthetische benadering psychologische moet leiden tot gebruiksvriendelijke ontwerpen voor de praktijk en tot fundamentele kennis voor de wetenschap. Doordat men de waarheid gevonden heeft is de conclusie niet ‘verder onderzoek is nodig’ maar ‘verder onderzoek is niet nodig want we weten hoe het zit’.
De tweede vraag, die aan de orde komt in Deel II ‘De oplossing’ is:” “Met welke oplossing krijgt men gebruiksvriendelijke computers?” De basis voor de oplossing is het gebruikelijke onderscheid in ‘Mens’ en ‘Computer’.
In de Oplossing wordt de mens opgevat als een systeem dat bewegings-, waarnemings-, taal-, geheugen- en denkhandelingen uitvoert met bijvoorbeeld een computer.‘ De handen typen of wijzen aan en de ogen kijken naar het scherm en lezen pictogrammen of woorden. Het geheugen helpt bij het bepalen van de betekenis van de waargenomen informatie en het verstand ten slotte zorgt ervoor dat de taak uitgevoerd wordt. Deze opvatting van een gebruiker lijkt voor de hand te liggen, toch vindt men deze niet zo vaak in de toegepaste cognitieve psychologie. De computer is meestal gespecificeerd als de interface techniek die gebruikt, zoals menu’s, invulformulieren, kommando taal, en spraakinvoer. De conclusie in dit proefschrift is dat een benadering vanuit de techniek geen inzicht geeft in de wijze waarop mensen werken met computers. In plaats daarvan kiest de Oplossing in dit proefschrift voor een benadering vanuit de eigenschappen.  Een interface bestaat uit eigenschappen die een directe relatie hebben met eigenschappen van psychologische processen die wat met deze eigenschappen doen. De benadering van uit de elementen geeft duidelijk aan welke eigenschappen dat zijn (bijvoorbeeld afmeting, vorm en contrast). Minder duidelijk zijn de eigenschappen van de combinaties van deze elementen.  Dit proefschrift stelt drie veldeigenschappen voor: hoeveelheid, afstand en structuur. Voor elk menselijk vermogen (bewegen, waarnemen, taal, geheugen en denken blijkt deze drie eigenschappen onderscheiden te kunnen worden.
De derde vraag is: “Leidt de Oplossing inderdaad tot gebruiksvriendelijke computers? Deel III ‘Experimenten’ test dit met vier eigenschappen: (visuele afmeting, visuele afstand, cognitieve hoeveelheid en cognitieve structur). De taken die onderzocht worden zijn eenvoudige uit het leven van alle dag, zoals het zoeken van een station in een lijst op en treinkaartautomaat, opmerken dat een treinkaartautomaat buiten werking is en het vinden van een trein op een dynamisch treinen bord.
Het eerste experiment (hoofdstuk 8) is eenvoudig. Met visuele afmeting verbetert de gebruiksvriendelijkheid van een lijst met stations. De veronderstelling is dat verschillende visuele eigenschappen waarmee men aangeeft dat de volgende letter komt in de alfabetische stationslijst, een effect hebben op de tijd die nodig is om een station te vinden. De Europese spoorwegen gebruiken verschillende layouts voor dezelfde lijst. Een daarvan is een lege knop met daarop de eerste letter van de stations die beginnen met die letter. Uit de Oplossing volgt welke layouts men kan toepassen. Eén daarvan is visuele afmeting. ‘Baarn’ als eerste station met de letter ‘B’ krijgt dan een extra grote letter ‘B’. Het blijkt dat dit ontwerp, dat met de Oplossing gevonden is, leidt tot een gebruiksvriendelijker ontwerp dan de gebruikelijke oplossingen van de Europese spoorwegmaatschappijen. Deze conclusie bleek niet alleen te gelden voor alfabetische stationslijsten voor knoppentreinkaartautomaten. Toen de interface techniek veranderde van ‘één knop - één station’ naar een ‘numerieke code voor stations’ bleek de verworven kennis ook toepasbaar op een codeautomaat. Toen vervolgens de codeautomaat vervangen werd door een touchscreenautomaat bleek dezelfde kennis wederom toepasbaar te zijn. Nader onderzoek naar de layout van een nieuwe letter in de lijst was niet nodig. Hoofdstuk 9 gaat in op de visuele veldeigenschap ‘visuele afstand’ en past de oplossing toe op twee taken: “Opmerken dat een automaat buiten dienst is” en “Opmerken van de instructies hoe men een bankbiljet in moet voeren.” Bij een grote visuele afstand merkt 6,4% van de gebruikers niet op dat de automaat buiten dienst is terwijl dit percentage bij een kleine visuele afstand 1.9% is. De tekst die aangeeft hoe men een bankbiljet in de automaat moet invoeren merkt 69% op bij een grote visuele afstand. Wanneer men de visuele afstand vermindert dan is dit percentage 78%. Beide experimenten laten zien dat de voorgestelde Oplossing leidt tot gebruiksvriendelijker ontwerpen dan de gebruikelijke. Bovendien blijkt de met de Oplossing verkregen kennis generaliseerbaar. Toen de ‘één button – één station’ automaat vervangen werd door een ‘numerieke code’ automaat werd de visuele afstand tussen station en code geminimaliseerd door beide aan te sluiten. Gebruikelijk is beide in een afzonderlijke kolom te plaatsen. Bij het ontwerpen van de volgende generatie, de touchscreen treinautomaat heeft ‘visuele afstand’ in sterke mate de bediening bepaald.
  Hoofdstuk 10 verbetert het zoeken van een trein op het vertrekbord dat hangt in de hal van Amsterdam CS te verbeteren door optimalisering van de eigenschap cognitieve hoeveelheid. Uit observaties bleek dat 62% van de reizigers in staat is de beste trein te vinden. De Oplossing suggereert dubbele treinen weg te laten. Het aantal reizigers dat de beste trein vindt neemt dan toe met 3% en de gemiddelde reistijd neemt af met 1,3 minuten. De Oplossing leidt dus tot een verbetering.Het laatste experiment gaat in op cognitieve structuur. Ook hierbij dient het vinden van een trein op een vertrekbord als voorbeeld. De Oplossing suggereert dat naast aanpassing van de cognitieve hoeveelheid ook aanpassing van de cognitieve structuur van het bord zal leiden tot betere prestaties van de reizigers.

Een experiment vergelijkt de in Europa gebruikelijke treinenvertrekborden met een minder gebruikelijke bestemmingenvertrekbord dat De Oplossing voorstelt. Op de onderdelen: het aantal juiste treinen, de vertraging, de zoektijd en het oordeel van reizigers scoort het bestemmingenbord beter dan voor het gebruikelijke treinenbord. Ook in dit geval leidt de Oplossing tot een gebruiksvriendelijker ontwerp. De conclusie blijkt toepasbaar bij andere interface technieken en borden zoals de routestrips die aangeven waar een trein stopt, het spoorboekje en menu’s van computerprogramma’s. Deze laatste zijn volgens de Oplossing een chaos.
  Wetenschappelijke experimenten moeten gestelde vragen beantwoorden. Maar ook wanneer de antwoorden die de experimenten geven duidelijk zijn blijkt er vaak nog volop discussie te zijn. Daarom test dit  boek de Oplossing ook op andere wijzen in deel IV: “Is de Oplossing werkelijk beter?
Dit  boek past de Oplossing toe op de wijze waarop men reisinformatie moet presenteren. Bij de experimenten is de conclusie toegepast op andere gebieden zoals automaten met een beeldscherm, koffieautomaten, spoorboekjes, bewegwijzering en op andere interface technieken zoals beeldschermen. In principe moet de Oplossing ook toepasbaar zijn op de wijze waarop informatie voor designers geordend is. Beide, reizigers en designers, gebruiken immers dezelfde psychologische processen om hun problemen op te lossen. Het  boek neemt deze uitdaging aan en test de Oplossing door na te gaan hoe drie andere Oplossingen informatie voor designers structureren. Volgens de Oplossing van dit  boek zijn deze andere Oplossingen chaotisch. Tot slot de laatste uitdaging, is de Oplossing chaotisch? Wat vindt de Oplossing van zichzelf?
Wat zijn nu de resultaten van dit boek? Natuurlijk, het is niet moeilijk gebruiksvriendelijke apparatuur te maken. Maar er is meer.
Het lijkt erop dat het maken van een gebruiksvriendelijk apparaat hetzelfde is als het maken van een theorie over het maken van gebruiksvriendelijke apparaten.Er is een Oplossing die kan testen of deze Oplossing zelf goed is.. Met de Oplossing krijg je ongebruikelijke ontwerpen, die, wanneer zij er eenmaal zijn, ineens als vanzelfsprekend gebruikelijke ontwerpen betiteld worden. Met de Oplossing wordt vooruitblikken terugblikken.Een van de opmerkelijke conclusies van dit  boek is dat ‘verder onderzoek niet nodig is’.
De Epiloog gaat terug naar de titel van dit  boek: “Waarom kunnen ontwerpers hun gebruikers niet begrijpen?” Tot op heden heeft het rookgordijn van wetenschap de psychologie kunnen vrijwaren aan de schuld van een van de grootste hedendaagse raadsels: waarom kunnen computers met hun geweldige capaciteiten niet communiceren met hun baas.Dit  boek voorziet dat wanneer onze kleinkinderen op onze tijd terugblikken zij niet kunnen begrijpen waarom computers vrijwel onbedienbaar waren. Zij zullen de cognitieve psychologie in het rijtje van de verdachten plaatsen.
To top.

More applied cognitive psychology in:

Interface, GUI and web design        

Public information systems, public transport, road and waterway traffic, signposting  

Grammar for graphics: Comprehensible signs on streets, stations and screens            

How to manage our daily life in a technical future    

Arithmetic in primary school: education, computers, and future

ETCS mmi, high speed train drivers train control interface ERMTS).      

To the top of this page.

Pages showing the application of this book

To top.

Search in humanefficiency.nl


cognitive psychology,  interface design, mmi,  usability, web page design

+31 (653) 739 750
Parkstraat 19
3581 PB Utrecht

Chamber of commerce number: 39057871, Utrecht.

To top.