interaction techniques level 2 prepared by: rhr first prepared on: nov 23, 2006 last modified on:...
TRANSCRIPT
Interaction Techniques
Level 2
Prepared by: RHR First Prepared on: Nov 23, 2006 Last Modified on:Quality checked by: MOH
Copyright 2004 Asia Pacific Institute of Information Technology
HCI & UsabilityCE 00306-2
Human Computer Interaction & Usability
Interaction Technique
Topic & Structure of the lesson
• Norman’s Gulfs of Execution and Evaluation• Interaction style
– Command Line– Menus– Questions and answers– Form – fills– WIMP
Human Computer Interaction & Usability
Interaction Technique
Learning Outcomes
• At the end of this lecture, you should be able to:– Select the appropriate interaction
technique for the interface design
Human Computer Interaction & Usability
Interaction Technique
Key Terms you must be able to use
If you have mastered this topic, you should be able to use the following terms correctly in your assignments and exams:
•Norman’s gulf of execution and evaluation•Interaction style
•Command line•Menus•Question and answer•Form – fills•WIMP
Human Computer Interaction & Usability
Interaction Technique
Models of interaction
• Norman’s Gulfs of Execution and
Evaluation – The user formulates a plan of action, which is
then executed at the computer interface. When the plan, or part of the plan, has been executed, the user observes the computer interface to evaluate the result of the executed plan, and to determine further actions
Human Computer Interaction & Usability
Interaction Technique
• To get something done…– Start with a goal – the goal that is to be
achieved– Take action to manipulate something– Check against your goal
Models of interaction
Human Computer Interaction & Usability
Interaction Technique
Models of interaction - Execution
2. Intention to act
3. Sequence of actions
1. Goals
The world
4. Execution of the action sequence
Human Computer Interaction & Usability
Interaction Technique
The seven stages of action1. Forming the goal
– Something to be achieved– E.g. “make a nice meal”
2. Forming the intention– Specific statements of what has to be done to achieve the
goal
– E.g. “make a chicken casserole using a can of prepared
sauce”
Models of interaction - Execution
Human Computer Interaction & Usability
Interaction Technique
The seven stages of action3. Specifying an action sequence
– The precise sequence of operators that must be performed to effect the intention
– E.g. “defrost frozen chicken, open can”
4. Executing an action– Actually doing something– E.g. “opening the can”
Models of interaction - Execution
Human Computer Interaction & Usability
Interaction Technique
The world
5. Perceiving the state of
the world
1. Goals
7. Evaluation of interpretation
6. Interpreting the perception
Models of interaction - Evaluation
Human Computer Interaction & Usability
Interaction Technique
The seven stages of action5. Perceiving the state of the world
– Perceiving what actually happened– E.g. the experience of smell, taste and look of the
prepared meal
6. Interpreting the state of the world– Trying to make sense of the perceptions available– E.g. putting those perceptions together to present the
sensory experience of a chicken casserole
Models of interaction - Evaluation
Human Computer Interaction & Usability
Interaction Technique
The seven stages of action7. Evaluating the outcome
– Comparing what happened with what was wanted
– E.g. did the chicken casserole match up to the requirement of “a nice meal”?
Models of interaction - Evaluation
Human Computer Interaction & Usability
Interaction Technique
• What are the 7 stages of Norman’s gulf of evaluation and execution?
Quick Review Question
Human Computer Interaction & Usability
Interaction Technique
Interaction Style
• Dialog between the computer and user.
• Identification of interaction styles:– Command Line Interface
– Menu
– Natural Language
– Question/ answer and query dialogue
– form -fills and spreadsheets
– WIMP
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Command Line
• First interactive dialog style to be used
• A mean of expressing instruction to the computer directly
using function keys, single characters, abbreviations or whole
word command
• user responds to a prompt on the screen by entering an
appropriate command
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Command Line
• Benefits of command line:– It offers direct access to system functionality
– Quick to use.
• The command can be applied to many objects at once
– Easily extensible
– Suitable for experience user
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Command Line
• Disadvantages of command line:– Difficult to use
– Difficult to learn
– Difficult for error correction
– Difficult for novice user
– Text only data representation
Hint: using consistent and meaningful commands
and abbreviations
Human Computer Interaction & Usability
Interaction Technique
Review question
• Can you suggest some guidelines of using the command line interface based on the above advantages and disadvantages?
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Command Line
Design guidelines:
• Offer maximum flexibility
– Conduct task analysis to determine the necessary
commands
• Facilitate command remembering
– Use meaningful, descriptive names
– Use consistent format of the command line
– Provide on-line help
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Command Line
Design guidelines:• Facilitate error correction
• Give feedback on both successful and unsuccessful commands
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Menus
• A set of options displayed on screen
• Relies on recognition rather than recall
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Menus
• Benefits of Menus:
– Easy to use, reduces memorisation
– Structure the user’s decisions
– Easy to program
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Menus
• Disadvantages of Menus:
– Limited choices per menu– Slow to use in large systems– Multi-user systems
• slow response times
– Can take up a lot of space
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Menus
• Can you suggest some guidelines of using the menu and navigation interface, based on the above advantages and disadvantages?
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Menus
• Design guidelines:– Group logically related options– Various categories of grouping:
• Alphabetical • Categorical • Conventional • Frequency
– Limit options to 7 per menu approximately, or break into sections
– Avoid excessively deep hierarchies– Options that are not available at a given time should be
faded (grayed).
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Question and answer
• Consists of computer prompt, i.e. question, set of choices, and a response from the user.
• Next question may depend on previous answer given.
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Question and answer
• Benefits of Q&A:– Easy to use for naïve and novice users– Conversational systems– Computer initiated and controlled dialogue
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Question and answer
• Disadvantages of Q&A:– Slow to use
– Time to read
– there is limited support for going back to correct errors that might have been made in earlier questions.
– Generally they are quite slow to use - every question must be answered in order to get through the sequence
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Question and answer
• Can you suggest some improvements of the question and answer interface, based on the above advantages and disadvantages?
Human Computer Interaction & Usability
Interaction Technique
Interaction Style – Question and answer
• Design guidelines:– Only one question at a time– Re-display previous answer (s) if replies are
linked– Keep sequences compatible with source
document or user task model– Display format of acceptable responses
Human Computer Interaction & Usability
Interaction Technique
Interaction Style: Form – Fills
• Designed for clerical workers– Requires little experience with computers– To enable them to carry out repetitive clerical
data collection tasks.– Mimicked paper forms in order to retain the
characteristics of the manual task– Designed for a specific type or task.
Human Computer Interaction & Usability
Interaction Technique
Interaction Style: Form – Fills
• Advantages– Forms offer a neat, structured way of
gathering information.
• Disadvantages– A form has to be designed specifically for
each task. – Users will require a certain level of typing skill
Human Computer Interaction & Usability
Interaction Technique
Interaction Style: Form – Fills
• Can you suggest some improvements of the form - fills interface, based on the above advantages and disadvantages?
Human Computer Interaction & Usability
Interaction Technique
Interaction Style: Form – Fills
• Design guidelines:– Text box :
• Maximum size of text-box can be determined beforehand.
– In many fields it is possible to provide a default value for a data field
– In some forms, certain values might be required, other optional.
• For required items, program might not proceed to other fields until value is entered.
Human Computer Interaction & Usability
Interaction Technique
Interaction Style: Form – Fills
• Design guidelines:– Interdependencies can be incorporated in the
program. • For example, if one element asks if user is
pregnant, then 'female' is automatically entered in the 'sex' field.
Human Computer Interaction & Usability
Interaction Technique
Interaction Style: WIMP
• Windows, icons, menus and pointers• The user carries out some physical action
(e.g. clicking, dragging) rather than typing commands with complex syntax
• The results of the action are seen immediately and, usually, actions are reversible
Human Computer Interaction & Usability
Interaction Technique
Interaction Style: WIMP
• Advantages– Novices can learn the basic functions quickly,
usually through demonstration and practice rather than from formal instruction or a manual.
– Intermittent users can retain the main operational concepts of the interface because it involves visual recognition.
– Error messages are rarely needed because most actions are reversible.
Human Computer Interaction & Usability
Interaction Technique
Interaction Style: WIMP
• Advantages– There is immediate feedback as to whether or
not the user's goals have been achieved.– Users are less anxious, again because they
know actions can be reversed.
Human Computer Interaction & Usability
Interaction Technique
Summary of Main Teaching Points
• Interaction is the heart of all modern interfaces and is important at many levels from the ordering of screens to the clicking of a button.
Human Computer Interaction & Usability
Interaction Technique
Q & A
Question and Answer Session