Study with the several resources on Docsity
Earn points by helping other students or get them with a premium plan
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
An overview of Human-Computer Interaction (HCI), focusing on the importance of usability in design. It covers various aspects of HCI, including the role of humans and computers, the scope of HCI, its goals, and principles. The document also discusses the contribution of different disciplines to HCI and provides examples of good and poor design. It emphasizes the need for simplicity, progressive disclosure, constraints, feedback, protection, control, and Norman's principles of usability.
Typology: Study notes
1 / 108
This page cannot be seen from the preview
Don't miss anything!
How Human interacts with Computer:
Observation of interactions between people & computers, e.g., Find examination papers via our library Web Analysis of the involved interactions, e.g., Are all the steps involved are necessary? Investigating outcomes after interacting with computers, e.g., Can the user perform his task? Does he enjoy working with the computer?
Human: Individual user, a group of users working together, a sequence of users in an organization
Computer: Desktop computer, large-scale computer system, smart phone, embedded system (e.g., photocopier, microwave oven), software (e.g., search engine, word processor)
User interface: Parts of the computer that the user contacts with, e.g., screen, mouse, keyboard, switch button, knob
Interaction: Usually involve a dialog with feedback & control throughout performing a task (e.g., user invokes “print” command and then interface replies with a dialog box)
Lamp
Function/objective: to illuminate the environment
Interface: power switch button
Functional part: light bulb
Interaction: press “On”, light on; press “Off”, light off User tasks: turn on the lamp, turn off the lamp
Word processor
Objective: to edit a document
Interface: windows, icons, menus, pointers (WIMP), etc.
Functional part: sub-routines for command execution, file handling, etc.
Interaction: use mouse to click the “WORD” icon, observe WORD is invoked, use mouse to click “FILE” icon, …
User tasks: edit file, save file, etc.
In the past, computers were expensive & used by technical people only
Now, computers are cheap and used by non-technical people (different backgrounds, needs, knowledge, skills) ⇒ Computer and software manufacturers have noticed the importance of making user-friendly interfaces: including easy to learn, easy to use, save people time e.g., Is your washing machine user-friendly? ⇒ We also desire good user experience e.g., Do you feel pleasure and satisfaction when using your smart phone?
Use & Context: Find application areas for computers
Human: Study psychological & physiological aspects e.g., study how a user learns to use a new product, study human typing speed
Computer: Hardware & software offered e.g., input & output devices, speed, interaction types, computer graphics
Development: Design, implementation & evaluation
Understand the factors that determine how people use technology
At physical level, HCI concerns selecting the most appropriate input devices and output devices for a particular interface or task
Determine the best type of interaction, such as direct manipulation, natural language, icons, menus
For systems that include computers, develop or improve Safety Utility Effectiveness Efficiency Usability Appeal
Utility: extent of providing the right kind of functionality so that users can do what they need or want to do High utility Scientific calculator provides many mathematical operations, built-in formulae, and is programmable Low utility Software drawing tool does not allow free-hand drawing but only supports polygon shape drawing
Effectiveness: concern a user’s ability to accomplish a desired goal or to carry out work Find a master thesis in our library Web
Any difference between utility and effectiveness?
Consider a shopping Web that provides all the information, instruction and server-side support required to perform an on-line purchase. However, the users cannot figure out how to find the items they want to buy.
Efficiency: a measure of how quickly users can accomplish their goals or finish their work using the system Find a book whose title contains “human computer interaction” in our library Web How about a Ph.D. thesis whose author’s last name is “Cheng”? How about the newest book in the subject of “human computer interaction”?
Usability: ease of learning and ease of use
Can I use the basic functions of a new digital camera without reading the manual? Does the software facilitate us to learn new functions easily?
Appeal: how well the user likes the system
First impression Long-term satisfaction
Use Microsoft WORD as an example:
Goals Achieved? Example Safety Yes Warning for “Exit before Save” Utility Yes A lot of word processing functions is provided Effectiveness Yes A science student can edit equations Efficiency Yes Default template avoids initial document setting Usability Yes Icons help ease of learning Appeal Yes Interface is attractive
e.g., Cafe de Coral uses a business management system (BMS) to increase productivity, e.g., food photos are available on cashier display and operators do not need to memorize food codes, automatic collection of sales information at all shop saves staffing cost
Hong Kong Economics Times (8 Oct. 2004)
Lowering support costs If the product is not usable, calls to customer support can be enormous e.g., If a washing machine is difficult to use even after reading the instruction manual, many users will call the customer service, which will result in high cost
Reducing development cost
Avoid implementing features users do not want and creating features that are annoying or inefficient e.g., If there are too many unnecessary confirmation dialog boxes in using a word processor, it is likely this product needs to be redeveloped
