Users and User Characteristics

1. Users and User Characteristics ISDE 2011

2. Contents • Users - Designing for diversity • Characteristics of users ISDE 2011

3. Recap - Scope of HCI • Designing usable systems requires us to have knowledge of: • The users who will use the system. • The tasks for which it will be used. • The environment in which it will be used. • So designers need knowledge of: • The physiological and psychological capabilities of the user. • The types of tasks that users will be expected to carry out. • The organisational and environmental aspects of the user’s task. • The technical constraints of the system. ISDE 2011

4. Users! • Who are the users? • What do we need to know and find out about users? • What ‘user characteristics’ are important in interface design? ISDE 2011

5. Users ISDE 2011

6. More Users ! ISDE 2011

7. ISDE 2011

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9. Designing for Diversity • The wide range of human abilities, backgrounds, motivations, personalities and intelligence presents major challenges for interactive system designers. • They need to have an understanding of: • physical characteristics • cognitive and perceptual abilities • personality differences • general abilities • These are all characteristics which apply to people in general, we shall also consider characteristics which apply specifically to potential system users. ISDE 2011

10. User Characteristics relevant to UI Design • Physical abilities & disabilities • Pesonality • Age – Sex – Culture • Education • Computer/IT knowledge • Motivation • Attitude ISDE 2011

11. Physical Characteristics - Activity • Think of a car and its interface (controls). What physical aspects need to be considered? • Height of users – seat height • Arm and Leg Length - position of controls • Feet Size – Width & Space between pedals • Vision – Size of text/labels on instruments controls audio equipment etc • Hearing – volume/pitch of audio signals – indicators, seat belt low fuel ISDE 2011

12. User Characteristics • Basic data about human dimensions comes from anthropometry. • What is average? • What compromises must be made? • e.g. keyboard spacing, mouse size and shape. • Adjustments to interface, e.g. brightness of VDUs. • These aspects of the physical design of workstations is part of Ergonomics. ISDE 2011

13. Personality • Many differences exist between individuals’ personalities: • Extroversion/Introversion; • Convergent/Divergent thinking; • Feeling/Thinking. • Personality differences will affect how people interact with the system: • preferences for interaction styles, • graphical or tabular representations, • motivation towards the task. ISDE 2011

14. Dr Phil • Who are you!!! ISDE 2011

15. Example – Sat Nav • User preferences for • Voice – Male v Female - accents • How information is presented – map v list of directions • How frequently reassured about being on course/correct route • Eg Cautious/timid type - frequently ISDE 2011

16. User characteristics: physical differences • Age (use larger fonts for older people) • Vision limitations, such as colour blindness • Other physical limitations that might restrict movement • Small children don’t have good fine-muscle control: see big buttons on next slide ISDE 2011

17. Big buttons for little people ISDE 2011

18. User characteristics: cultural differences • Language (how many languages should be supported) • Education (reading level) • Profession (specialized vocabularies) • Attitude towards computer systems (e.g technophobia amongst elderly users) • Corporate style: what are you trying to convey to whom? ISDE 2011

19. System Related User Characteristics • What characteristics can you expect of the users of your interface? • frequency of use • discretion to use the system • knowledge of the task which the system will support • knowledge of computers • experience of other similar systems • general abilities, e.g. literacy, vision • attitude towards computers (and your system) • existing skills (keyboard, mouse) ISDE 2011

20. Some Design Implications • frequency of use: amount of skill building that takes place and knowledge user can be expected to retain • discretion to use the system: impact of poor usability • knowledge of the task which the system will support: level of support at interface provided for how to complete tasks • knowledge of computers: level of guidance provided • experience of other similar systems: user expectations and use of familiar interface conventions • general abilities, e.g. literacy, vision: assumptions made about presentation of text, motor skills, intelligence • attitude towards computers: level of help and guidance and way in which system is introduced to users • existing skills (keyboard, mouse): choice of interaction style to use to exploit existing skills ISDE 2011

21. Categorisation of Users • If designing an interface need to be able to categorise users • Easier for small systems much more difficult for large systems • Primary or secondary user • 3 D framework • task expertise • computer expertise • frequency of use ISDE 2011

22. Differences between user groups… • Consider the design of an on-line hotel reservation system for a multi-national hotel chain • Talk to the person next to you and make a list of some of the differences between the groups of people who will use the system • Identify who are the ‘stakeholders’ of this system ISDE 2011

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24. Differences – Some Examples • Frequency of use • Cultural • Motivation • Computer Knowledge/skills • Experience of other hotel systems • General ability – literacy education • Physical differences ISDE 2011

25. Primary and secondary users • Primary user: the person who actively uses the site: • Airline reservation clerk • Help desk staff • Secondary user: the person being served by a primary user: • Airline passenger • Customer who called the support line ISDE 2011

26. Three-Dimensional Framework (high) • Three Dimensional Framework for User Classification Knowledge of Computers (high) Frequency of Use (low) Knowledge of Task (high) ISDE 2011

27. 3 D framework applied to Occupational Categorisation of Users • Broad occupational classification as: • computer professionals • professionals without computer experience • skilled clerks • naïve users • special groups • Remember the first four of these are broad classifications - make sure you understand your particular user group(s). ISDE 2011

28. Computer professionals • Classification: • computer knowledge - high/very high • task knowledge - high • frequency of use - high • Understand software and hardware. • Intelligent, well-educated and highly motivated (often). • May want to customise software for own needs. • Have little patience, like rapid response in software. • Sensitive to shortcomings in software. NOT typical of the majority of users ISDE 2011

29. Design implications • Provide for high degree of sophistication in interface: • range of functions provided, • flexibility to combine functions to provide new commands, • possibilities to customise interface to own needs. • Lower requirement for user support than with other user types. • Can utilise programming languages and extensible command languages (e.g. macros and scripts). ISDE 2011

30. Professionals without computing experience • Classification: • computer knowledge - low/moderate • task knowledge - high • frequency of use - varies, low-high • Know little about computers. • Often not interested in computers. • Probably have not read any documentation. • Lack patience. • Have high expectations of performance. • Intolerant of software errors. ISDE 2011

31. Motivated to accomplish the job/task the system was designed to support. • May be discretionary users of systems. • High degree of usability is critical for this group. • Design implications • Important to support the user ‘guessing’ or experimenting with how operations can be carried out at the interface. Consistency and a close match to the user’s task model is important. • Frequency of use determines how much the user can be expected to learn short cuts and accelerators. • User support provided by the interface is important. ISDE 2011

32. Skilled clerks • Classification: • computer knowledge - low • task knowledge - high • frequency of use - high • May use a machine several hours a day. • Develop very strong user skills. • Do not have a high degree of computer sophistication. • Want rapid responses in software. • Quickly grow impatient with features designed for less experienced users if these features slow them down. • Usage is not usually discretionary. ISDE 2011

33. Design implications • Can anticipate significant learning of routine operations to take place, so can make use of abbreviations and codes for data input. • Can expect strong user skills to be developed, such as keyboard skills. • Error messages must be clear and provide specific guidance for recovery. • Cannot expect users to develop deeper knowledge or understanding of the computer system without specific training. ISDE 2011

34. Naïve users • Classification: • computer knowledge - very low • task knowledge - varies, low - moderate • frequency of use - assume low • Know (nearly) nothing about computers. • Cannot assume significant learning process, i.e. each interaction with the system should be treated as if it were the user’s first. • May feel intimidated by using a computer. • Ease of learning is important usability criterion. • Use of system is usually discretionary. ISDE 2011

35. Design implications • Every type of user error must be trapped. This type of user will not be able to infer what is happening or the cause of an error condition. • Require explicit on-screen prompts for each step of the dialogue. • High degree of user support and a low degree of sophistication is required in the interface. ? ISDE 2011

36. Special groups • Do not make assumptions that the users of your interface/system fall into neat categories. • Consider in particular design for users with • Sensory impairments – partially sighted – colour blind - deaf • Physical impairments – lack of mobility – arthritis • Techniques exist for analysing the characteristics of users in detail ISDE 2011

37. Assumed knowledge: about computers • How much knowledge do you assume the user group has about computers in general? • Can you assume familiarity with graphical user interfaces (GUIs) – if not, don’t expect the user to know what a combo box and how to use it • Can you assume familiarity with using the internet –if so, you can assume familiarity with conventions and common facilities, and with using GUIs • Important particularly when designing for the (older) general public • Increasing public awareness of internet and computer use (but this can’t be taken for granted yet- 2009 still approx 10 million never or seldom used!) ISDE 2011