HCI notes TOPICDxE Designing to ﬁt human capabilities Designing for error 1. What are the human capabilities?. Human factors 2. Human errors vs. design errors 3. Three different design approachesHCI notes: Designing for error
1. What are the human capabilities? HUMAN CAPABILITIES What are the human capabilities? ■ Question too broad. It involves at least two sets: One with human average capabilities (in a particular context) and other one with human disabilities (also in a certain context)[topic Design for special needs]. It can be bounded in a context: HCI. What are the human capabilities in relation to the use of computers? (Digital Tools)
1. LIMITATIONS AND CAPABILITIES Physical Cognitive Social behavior motricity perception agility memory resistance behavior ... limited attentional resources ...and we are back to the topic of human models (HCP)
1. HUMAN FACTORS multidisciplinary ﬁeld (psychology, engineering, industrial design, statistics, operations research and anthropometry) understand the properties of human capability [human factor science] apply this understanding to the design, development and deployment of systems and services. [human factor engineering] focuses on how people interact with tasks, machines (or computers), and the environment with the consideration that humans have limitations and capabilities. Evaluate "Human to Human," "Human to Group," "Human to Organizational," and "Human to Machine (Computers)" methods Focus groups | Iterative design | Meta-analysis | Task analaysis | Think aloud protocol | User analysis | wizard of Oz
2. Human error vs. design error Human error? Phobos 1 (1988) | In 1988, the Soviet Unions Phobos 1 satellite was lost on its way to Mars. Why? According to Science magazine, "not long after the launch, a ground controller omitted a single letter in a series of digital commands sent to the spacecraft.
2. “People err. That is a fact of life. People are not precision machinery designed for accuracy”. Donald Norman Cognitive Errors (“Mistakes”) Non cognitive Errors Mistakes are errors in choosing an (“slips & lapses”) objective or specifying a method of slips are errors in carrying out an achieving it intended method for reaching an objective "The division occurs at the level of the intention: (A person establishes an intention to act) If the intention is not appropriate, this is a mistake. If the action is not what was intended, this is a slip."
2. How many passwords you drive in your daily life? How many of them are repeated? How many are small variations of the same? Me?. About 17 email1 Bank account email 2 Bank online pass This is very far from work email Upf user the “magic number 7”! computer 1(home) Upf library user (out from human capabilities) computer 2 (work) website user server work snapﬁsh Spotify hosting Facebook Skype George A. Miller Linkedin ... How do we solve it?...
2. with unsafe passwords! Use common and Repeat the same password predictable passwords. for everything Human error?...NO! why?.. Designing for error: outside human capabilities.
3. Three different design approaches Approaches to prevent design errors... Designing for error... occurs because the designer ignores (some) human capabilities. TECHNOLOGY-oriented HUMAN-centered approach approach (consider the human factor)
3. TECHNOLOGY-oriented HUMAN-centered approach approach ■ Prioritizes computer based ■ needs, wants and limitations of end information processing and users are given extensive attention at technology-mediated each stage of the design process. communications over human and their communicative collaboration. UCD tries to optimize the design around user. human Cooperative design Participatory design machine Contextual design
3. TECHNOLOGY-oriented HUMAN-centered approach approach Imprecise Disorganized - Creative Obedient + Distractible Alerts to change Emotional Inventive human Illogical Exact Sorted + Not creative Structured - Impossible to distract Insensitive to changes machine Not emotional Logics Lacking imagination Humans lost: All attributes of people are negative while Humans win. the attributes of the machines are positive.Norman (1998) The invisible computer
3. TECHNOLOGY-oriented HUMAN-centered approach approach Both views are complementary: ■ People stand out for their qualitative skills. Those decisions are made ﬂexible, because they perform both human qualitative and quantitative assessments. ■ The machines are noted for their quantitative skills. Take logical decisions based on the quantitative evaluation of numerically speciﬁed variables and machine independent of context.
3. ACTIVITY-centered approach Musical instruments, the clock, writing systems... Why are such non-Human-Centered Designs so successful? All them have: arbitrary divisions, decisions and complexity. Artiﬁcial and unnatural. It takes people time to learned and become skilled. The reason for Norman is in the Activity-centered Design Develop with a deep understanding of the activities that were to be performed. Activities ≠ Task: an activity is a coordinated, integrated set of tasks. Example: Mobil phone Activity= communication | Task= looking up numbers. dialing. SMS...
4. REFERENCES Norman, D. A. (1990). Commentary: Human error and the design of computer systems. Communications of the ACM, 33, 4-7. Norman, Donald (1998) The Invisible Computer. Boston, MIT Press. Bogdan Calin (2006) Statistics from 10,000 leaked hotmail passwords. http://www.acunetix.com/blog/websecuritynews/statistics-from-10000-leaked-hotmail-passwords/ infosecurity.com (2009) http://www.infosecurity-magazine.com/view/3779/many-people-use-same-password-on-all-websites-says-cpp/ Hotmail leak: Most popular password? 12345 http://www.techradar.com/news/internet/hotmail-leak-most-popular-password-12345-641321 Humans factors. Wikipedia http://en.wikipedia.org/wiki/Human_factors