Lesson 1 - The Human PDF

IT9 LESSON 1: THE HUMAN ENGR. JOAN F. FERRANCO INTRODUCTION  The human, the user, is, after all, the one whom computer systems are designed to assist.  The requirements of the user should therefore be our first priority.  In order to design something for someone, we need to understand thei...

IT9 LESSON 1: THE HUMAN ENGR. JOAN F. FERRANCO INTRODUCTION  The human, the user, is, after all, the one whom computer systems are designed to assist.  The requirements of the user should therefore be our first priority.  In order to design something for someone, we need to understand their capabilities and limitations. Presented by: ENGR. JOAN F. FERRANCO What is HCI?  Human–Computer Interaction  Involves the design, implementation and evaluation of interactive systems in the context of the user’s task and work.  Human - user  individual user  group of users working together  sequence of users in an organization Presented by: ENGR. JOAN F. FERRANCO What is HCI?  Computer – any technology  general desktop computer  large-scale computer system  process control system  embedded system.  Interaction - any communication between a user and computer, be it direct or indirect.  Direct interaction – a dialog with feedback and control throughout performance of the task.  Indirect interaction - involve batch processing or intelligent sensors controlling the environment. Presented by: ENGR. JOAN F. FERRANCO Who is involve in HCI?  Multi-disciplinary Subject  Psychology  Sociology  Computer Science and Engineering  Business  Graphic design  Technical writing Presented by: ENGR. JOAN F. FERRANCO Theory and HCI  Three major issues of concern: the people, the computers and the tasks that are performed.  The system must support the user’s task, which gives us a fourth focus, usability: if the system forces the user to adopt an unacceptable mode of work then it is not usable. Presented by: ENGR. JOAN F. FERRANCO INPUT-OUTPUT CHANNELS  A person’s interaction with the outside world occurs through information being received and sent: input and output.  In an interaction with a computer the user receives information that is output by the computer, and responds by providing input to the computer – the user’s output becomes the computer’s input and vice versa.  Input in the human occurs mainly through the senses and output through the motor control of the effectors. Presented by: ENGR. JOAN F. FERRANCO Input-Output Channels  There are five major senses:  sight  hearing  touch  taste  smell.  Imagine using a personal computer (PC) with a mouse and a keyboard. (The application you are using has a graphical interface, with menus, icons and windows).  You receive information primarily by sight, from what appears on the screen  You may also receive information by ear - the computer may ‘beep’ at you if you make a mistake or to draw attention to something, or there may be a voice commentary in a multimedia presentation. Presented by: ENGR. JOAN F. FERRANCO Input-Output Channels  Touch plays a part too in that you will feel the keys moving (also hearing the ‘click’) or the orientation of the mouse, which provides vital feedback about what you have done  Smells to give warning of malfunction Presented by: ENGR. JOAN F. FERRANCO Vision  Human vision is a highly complex activity with a range of physical and perceptual limitations, yet it is the primary source of information for the average person  Vision begins with light  Experimental evidence suggests that in practice negative contrast (dark characters on a light screen) displays are preferred and result in more accurate performance Presented by: ENGR. JOAN F. FERRANCO Hearing  The auditory system can convey a lot of information about our environment.  Hearing begins with vibrations in the air or sound Presented by: ENGR. JOAN F. FERRANCO Touch  Touch provides us with vital information about our environment.  It tells us when we touch something hot or cold, and can therefore act as a warning. Presented by: ENGR. JOAN F. FERRANCO Movement  Motor control and how the way we move affects our interaction with computers  Hitting a button in response to a question involves a number of processing stages. Presented by: ENGR. JOAN F. FERRANCO HUMAN MEMORY  Memory is the second part of our model of the human as an information-processing system.  Sensory memory  act as buffers for stimuli received through the sense  Short-term memory  acts as a ‘scratch-pad’ for temporary recall of information.  Long-term memory  main resource Presented by: ENGR. JOAN F. FERRANCO HUMAN MEMORY  Design Considerations:  Minimize cognitive load by simplifying the interface and presenting information clearly.  Support memory retention with consistent design and reinforcement of key information.  Favor recognition over recall by using familiar visual cues and clear labels.  Provide immediate feedback and interaction history to aid memory and navigation.  Design for error prevention and easy recovery to reduce cognitive strain. Presented by: ENGR. JOAN F. FERRANCO EMOTION  Our emotional response to situations affects how we perform  Positive emotions enable us to think more creatively, to solve complex problems, whereas negative emotion pushes us into narrow, focused thinking.  A problem that may be easy to solve when we are relaxed, will become difficult if we are frustrated or afraid. Presented by: ENGR. JOAN F. FERRANCO INDIVIDUAL DIFFERENCES  Although we share processes in common, humans, and therefore users, are not all the same  We should be aware of individual differences so that we can account for them as far as possible within our designs.  Long term, such as sex, physical capabilities and intellectual capabilities.  Shorter term and include the effect of stress or fatigue on the user.  Still others change through time, such as age. Presented by: ENGR. JOAN F. FERRANCO PSYCHOLOGY AND THE DESIGN OF INTERACTIVE SYSTEMS  Understanding how humans receive, process and store information, solve problems and acquire skill  Recognition is easier than recall and allow users to select commands from a set (such as a menu) rather than input them directly. Presented by: ENGR. JOAN F. FERRANCO