Human Computer Interaction Universitas Gunadarma Dr Lily Wulandari Universitas Gunadarma Logo Seminar

TASK ANALYSIS

Introduction Poor application interfaces can hinder the processes that occur in the organization. This can be caused by the difficulty of using the application. A good user interface is needed to increase the usability of an application.

Task Analysis In order to fit the tasks performed by the user, the task analysis is carried out first Analyzing and describing how people do their jobs/work Examine users’ tasks to better understand what they need from interface and how they will use it

Task Analysis Task Analysis is the study of the way people perform their jobs. Aim is to determine: what they do what things they use what they must know Task analysis gathers both declarative and procedural knowledge Declarative: objects and relationships Procedural: task sequences, goals and subgoals Also dependencies and constraints

Components Three key components to include in discussing how people work Activities Artifacts (something observed in a scientific investigation or experiment that is not naturally present but occurs as a result of the preparative or investigative procedure.) Relations Don’t just focus on computer system artifacts and interactions Study related processes and objects in the environment that people may use and involve Example: office env---papers, whiteboards, etc.

Task Analysis Focus Focus on observable behaviors What are the practices, methods, steps, objects, …,used? Observe users, what they do, less so how they do it Not on internal cognitive state of user

Example Task: Cleaning House We must know about: vacuum cleaners, their attachments, dust bags, cupboards, rooms.

Input & Output Gather data: – Documentation Represent Data: – Interviews – Observation – Surveys/questionnaires – Automatic data recording/tracking Represent Data: – Lists, outlines, matrices – Narratives – Hierarchies & Networks – Flow charts

Data to be Gathered Information about users Description of environment Identify and collect information on how the user practices the task Description of environment – Where the tasks will be performed Major goals of the job – What will result in a successful end state? User preferences & needs

Data to be Gathered … For example task used by the user when using news mobile applications including, Task View the Latest News, Task View News, Task News Comments, Task Share News, Task View Bookmarks, Task Search News, Task News Categories, and etc.

Data to be Gathered … Tasks & Subtasks: – Physical – Cognitive – Communication Conditions under which these tasks are done Results/outcomes of tasks Requirements to perform task: – Information – Communication with others – Equipment

Data Gathering Tools: Docs Documentation Often contains description of how the tasks should be done (rather than how they are currently being done) Standards Manuals Histories Best Practices Domain Expert Description Expert describes how process should work, how tasks should be done “Knowledge-based” discovery

DGT: Interviews Interviews: Structured Unstructured Semi-structured Efficient Require training Unstructured Inefficient No training Semi-structured Good balance Often appropriate

Semi-structured Interviews Predetermine data of interest Plan for effective question types How do you perform task x? Why do you perform task x? Under what conditions do you perform task x? What do you do before you perform…? What information do you need to…? Who do you need to communicate with to…? What do you use to…? What happens after you…? What is the result or consequence of…? What is the result or consequence of NOT…?

DGT: Observation Observation In site, watch users do what they do Record with videotape To watch later, or again Take lots of notes, sketches May require coding the video later Focus on specific task-relevant behaviors in notes, but later convert to abstract subtasks

DGT: Questions, Think-aloud Questionnaires Exploratory vs. confirmatory Open-ended vs. categorical (exhaustive) What do you need to perform..? (list) Which of the following is most important to perform…? (select) If you ask it, use it. If you won’t/can’t use it, don’t ask it.

DGT: Questions, Think-aloud Think-aloud protocol Person talks about what they are doing, while they are doing it (or just before or after) Observer can ask probe questions Why did you just do that?

DGT: Logging Automatic tracking Keystroke/mouse click monitoring Timers Logs Physical location/movement trackers Cell phones Aware Home

Representing Data: Outlines Lists, outlines, matrices Use expanding/collapsing outline tool Add detail progressively Know in advance how much detail is enough Can add linked outlines for specific subtasks Good for sequential tasks Does not support parallel tasks well Does not support branching well

RD: Narratives Narratives Describe tasks in sentences Often expanded version of list or outline More effective for communicating general idea of task Not effective for details Not effective for branching tasks Not effective for parallel tasks

RD: Hierarchies Hierarchical Task Analysis (HTA) Graphical notation & decomposition of tasks Tasks as sets of actions Tasks organized into plans Clusters of subtasks with a preferred order and prerequisite conditions

Textual HTA

RD: Hierarchies Example Task Clusters Fixed sequence Optional tasks Waiting events Cycles Time-sharing Discretionary

Diagrammatic HTA

Refinement How to check or improve the initial HTA? Some heuristics are: paired actions where is “turn on gas”? restructure generate task “make pot” balance is “pour tea” simpler than “make pot”? generalise make one cup . . . or more

Refined HTA for making tea

Types of plan sequence 1.1 then 1.2 then 1.3 optional if the pot is full 2 wait when kettle boils, do 1.4 cycles do 5.1 5.2 while there are still empty cups parallel do 1; at the same time ...

RD: Networks Network / Entity-Relationship Diagrams Objects/people with links to related objects Stress relationship between objects and actions Links described functionally and in terms of strength Task: Develop design for final project objects - pens, paper, drawing tools, etc. actors - Mary, Bob, Sally composite objects - the “team”

RD: Networks Often list attributes, actions of objects Object: pen simple Attribute: color: red writing: on/off Object: Mary actor Actions: M1: make a sketch M2: organize meeting

RD: Flow Charts Flow Chart of Task Steps Combines Entity-relationship (network) with sequential flow, branching, parallel tasks. Includes actions, decisions, logic, by all elements of the system Abstracted Mature, well-known, good tools

Exercise Make a task analysis using diagrammatic HTA. The choice of case examples is up to you