Personas, Scenarios
& User Populations
Turn messy research into a usable picture of who you are designing for—without turning the persona into fiction.
By the end of class, you should be able to…
Define key tools
Explain persona, scenario, demographics and population stereotype.
Build from evidence
Distinguish research-based persona details from invented decoration.
Use carefully
Discuss advantages and disadvantages of personae, scenarios, demographics and population stereotypes.
Connect to decisions
Use a persona and scenario to identify requirements and questions for design.
A persona is a research summary with a human shape.
It represents relevant attributes found in a user population so designers can keep real needs visible during development.
Who?
Relevant demographic or contextual characteristics.
What do they do?
Patterns, habits, workarounds and attitudes found through research.
Why does the task matter?
Motivations, concerns, needs and opportunities.
The primary persona should be researched deeply.
Demographic context
Age, education, ethnicity, access challenges, family status, occupation—where relevant.
Abilities + skills
What can the user do confidently? What creates difficulty?
Environment
Physical, social and technological conditions surrounding the task.
Demographics describe groups; they do not automatically explain behaviour.
“Students aged 16–18.”
Helps define a population, but says little about how the product is actually used.
“Most carry a laptop in one hand while opening classroom doors.”
Directly informs the interaction problem.
A scenario describes a plausible use situation.
Maya leaves science carrying a laptop and water bottle. She reaches a heavy classroom door and must transfer the bottle to open it. The hallway is crowded and she is trying not to drop anything.
Relevant capability and behaviour.
Open and pass through the door while carrying items.
Crowded transition period with limited free hands.
Population stereotypes describe widespread responses—not every individual.
A population stereotype identifies responses that are widespread within a user population. It can support early design development, but it must not be treated as universal.
Recognize common responses
A widespread pattern can help a team anticipate common needs or behaviours in a user population.
Pattern becomes “everyone”
A widespread response can still hide important variation, exceptions and minority needs within the population.
Check the pattern
Use research to establish how widespread the response is and identify users who do not follow the common pattern.
Each user model is useful—and each can mislead.
| Tool | Useful because… | Limitation / risk | Better practice |
|---|---|---|---|
| Primary persona | Keeps important user patterns visible during design development. | Can oversimplify variation if one persona is treated as “everyone”. | Base attributes on research and keep checking against real users. |
| Scenario | Makes the persona’s task and context concrete. | It is an imagined sequence based on assumptions, so it may not match actual behaviour. | Make assumptions explicit and check them against user research or testing. |
| Demographics | Helps define and compare user populations. | Does not automatically explain motivations or behaviour. | Pair demographic information with behavioural evidence. |
| Population stereotype | Summarizes responses that are widespread in a user population. | A widespread response does not describe every individual and may hide important variation. | Use it as a population-level pattern and keep checking important exceptions. |
Persona or fiction?
A design team writes: “Jordan, 17, loves minimalist design, drinks matcha, hates plastic and always studies at coffee shops.” None of these details came from research.
What is the main problem?
Cluster evidence before writing the persona.
Collect
Interviews, observation, surveys, task evidence.
Find repeated patterns
Common needs, behaviours, motivations or limitations.
Prioritize relevance
Keep attributes that actually affect the redesign problem.
Represent
Create the primary persona and scenario grounded in those patterns.
The persona should generate better design questions.
Often carries objects in both hands
Observed during class transitions.
Can the task be completed one-handed?
A focused interaction question.
Reduce need for two-hand operation
Later justified through testing and user feedback.
Build a compact evidence-based persona.
Use this research summary: 8 students observed using a shared charging station; 6 keep phones connected while working; 5 pull cables sideways; 4 report difficulty seeing which port is available; two users use one hand because the other is holding a laptop.
Persona vocabulary
Retrieve first. Then check.
Can you retrieve it without looking back?
Before you leave…
Task Analysis & User Journey Mapping
Keep the evidence chain moving: user → research → decision → test.
Explain today’s key ideas without notes, then apply one idea to a different product, user or design context.