Data Gathering

• Purpose:– To collect sufficient, relevant and appropriate data

to develop a set of stable requirements

• Data:– Tasks performed– Goals– Context– Rationale for status quo

Data gathering techniques

• Interviews

• Focus Groups and workshops

• Questionnaires

• Naturalistic Observation

• Studying Documentation

Choosing between techniques

Some basic data gathering guidelines

• Focus on stakeholders’ needs

• Involve all stakeholder groups• Involve multiple representatives from each group• Use a combination of techniques• Support sessions with props• Run a pilot session• Know what you’re looking for• Record the session carefully (video/audio?)

Data interpretation and analysis

• There are a variety of methodologies for describing the data and diagramming for analysis

• Bottom line: find a method which is comfortable for you and your organization

• Develop templates so that all members of your organization are using the same method

Task Description

• Much of the data gathered will consist of descriptions of tasks performed by users– Now (old system)– Future (new system)

• Important to consider alternative ways to capture this information

Scenarios

• An “informal narrative description”

• Describes human activities or tasks in a story• Using vocabulary of the user• Relatively unstructured• Often the way users will describe a task• User’s task orientation – not necessarily technology• Caution: are they saying what they really do, or what

they SHOULD do?

Use Cases

• Emphasis on user-system interaction, rather than user’s task itself

• Identify “actors”, then capture the actors goals

• Define the “normal course” through the use case, numbering the steps

• Then identify alternative courses, with numbers corresponding to steps replaced

Essential Use Cases

• Tries to combine best of both Scenarios and Use Cases

• More general than scenarios (i.e. abstract)

• Avoid system assumptions of use cases

Task Analysis

• A form of analysis developed to understand cognitive processes

• Historically used in human factors engineering to evaluate training needs and incremental workplace improvements

• Readily applied to human/computer interaction

Hierarchical Task Analysis (HTA)

• Break a task down into subtasks, recursively

• Group subtasks together as “plans” that specify how they might actually be performed

• Focuses on physical and observable actions, including those not related to technology

• Starts with a user goal, and tasks associated with achieving it

Example: Making sushiMake Makisushi

3Prepare Fish

2Prepare Veggies

1Make Rice

4Make Rolls

1.2Prepare Vinegar

1.1Cook Rice

1.3Mix and Cool

ExampleMake Makisushi

3Prepare Fish

2Prepare Veggies

1Make Rice

4Make Rolls

2.2Slice Cucumber

2.1Slice Avocado

2.3Cut Scallions

2.4Slice Daikon

ExampleMake Makisushi

3Prepare Fish

2Prepare Veggies

1Make Rice

4Make Rolls

3.1Slice Salmon

3.2Slice Tuna

3.3Prepare Prawns

3.3.1Steam Prawns

3.3.2Flay Prawns

ExampleMake Makisushi

3Prepare Fish

2Prepare Veggies

1Make Rice

4Make Rolls

4.2Ingred on Rice

4.1Rice on Nori

4.3Roll with Mat

4.4Slice Rolls

HTA (cont’d)

• Tasks within a level are not necessarily performed sequentially– Could be any order, or even be concurrent

Make Makisushi

3Prepare Fish

2Prepare Veggies

1Make Rice

4Make Rolls

3.1Slice Salmon

3.2Slice Tuna

3.3Prepare Prawns

3.3.1Steam Prawns

3.3.2Flay Prawnse.g. Can cook rice while

preparing veggies

HTA (cont’d)

• Tasks within a level are not necessarily performed sequentially– Could be any order, or even be concurrent

• Tasks are best numbered to facilitate documentation and reference

Make Makisushi

3Prepare Fish

2Prepare Veggies

1Make Rice

4Make Rolls

3.1Slice Salmon

3.2Slice Tuna

3.3Prepare Prawns

3.3.1Steam Prawns

3.3.2Flay Prawns

HTA (cont’d)

• Tasks within a level are not necessarily performed sequentially– Could be any order, or even be concurrent

• Tasks are best numbered to facilitate documentation and reference

• Tasks are decomposed until they are “atomic”– Not readily decomposed further– Relatively simple and easy to understand– Things needed to complete the task can be identified

Make Makisushi

3Prepare Fish

2Prepare Veggies

1Make Rice

4Make Rolls

3.1Slice Salmon

3.2Slice Tuna

3.3Prepare Prawns

3.3.1Steam Prawns

3.3.2Flay Prawns

e.g. Just need a knife

Needs Assessment Exercise

• In groups, choose one person to be the “user”

• Gather data about how that person looks for an apartment

• Write down a hierarchical task analysis

Exercise Discussion

• Which method or combination of data gathering methods did you use?

• Why?