The photo that would not scan
A gym opens a new app. You log in with your face. It works for your friend. For you it says "face not found" again and again.
You stand at the door while others walk in. Is the app broken? Or was it only tested on some faces?
This is audience exclusion: a system that works well for some people and badly for others.
Key words
| Word | What it means | Example |
|---|---|---|
| Audience exclusion | Some of the people a system is for cannot use it well. | A face scanner that does not work for some skin colours |
| Bias | Treating some people less fairly, often without meaning to. | A tool tested on one group only |
| User experience | How easy and pleasant a system is to use. | Few steps and clear words |
| Accessibility | Designing so people with extra needs can use it. | Captions on a video |
| Screen reader | A program that reads the screen aloud. | Used by a blind person |
| Contrast | How different the text colour is from the background. | Black on white |
| Reputation | What people think about an organisation. | Known as fair |
The cells students fill in are left blank in this preview.
Quick check: who is left out?
Have a go
Quick check: who is left out?
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.
Bias: how it gets in
Nobody plans to leave people out. It happens in quiet ways.
Data bias: the system learned from data about only one group. A voice tool trained on adult voices may not understand children.
Design bias: the team who designed it all think alike, so nobody asks "what about people who are not like us?"
Testing bias: it was tested on a few kinds of people and devices only.
Poor user experience
A system can leave people out without any bias. It may simply be hard to use.
Tiny buttons are hard to press for people with shaky hands. Pale grey text on white is hard to read. Long forms with 40 questions make people stop and leave. Hard words confuse people who read English as a second language. A site that only works in one browser does not work for people who use another.
Problems, and who they stop
| Problem | Who is left out | A simple fix |
|---|---|---|
| No captions on videos | Deaf and hard of hearing people | Add captions |
| Pale grey text on white | People with weak sight | Use strong contrast |
| Pictures with no text description | Blind people using a screen reader | Add a short description to each picture |
| Only one language | People who read another language best | Offer more languages and plain words |
| A 40 question form | Everyone in a hurry | Ask only what you need |
| Works only on new phones | People with older devices | Test on old devices too |
The cells students fill in are left blank in this preview.
Scenario: find the problem
Have a go
Scenario: find the problem
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.