Daily UX Crash Course — User Psychology: 28 of 31

One of the opinions that is common in UX — and from people who don’t understand science — is the idea that you can’t measure feelings. That isn’t entirely true, especially when we’re measuring groups of feelings. So today we will learn:

Can You Measure a Soul?


(Just starting the User Psych Crash Course? Start here.)


A soul?!

Ok, ok… it may sound religious, but I am referring to the emotional, subjective parts of the human experience.

The soaring highs, the heart-breaking lows. The pains, the gains, the walks of shame.

Call it whatever you want. It’s who we are.

Point is: can we measure it? Yes we can!

Feelings produce actions and decisions, and those things can be measured pretty easily.




In UX we usually don’t have an fMRI machine in the office, but just as an example: there is an emerging industry that measures people’s brains to discover which version of an ad or a movie creates the strongest emotions.

This is essentially an A/B test, with much cooler data than we usually get. When you do an A/B test, you are doing the same thing, but using actions instead of brain scans as your evidence.


Groups are Reliable. Individuals, not so much.

As we learned earlier in this crash course, motivations (feelings) make people do stuff. Actions.

You might Like a photo, retweet an article, or embarrass yourself in front of millions of people, because 50 people said you should.

In UX, our goal is to create actions, not just feelings. We motivate people so they will act in a certain way, which is helpful for everyone (including us).

When we measure individual people, we have to ask them face-to-face, otherwise the details have too much influence to be reliable. A user might act differently because of the news this morning, or their personal interests, or because they are killing time on the toilet at work.

When you put a few thousand or a few million people in a group, however, those individual differences don’t matter. The soul of the group becomes clear in the data.

When we talk about “the average person” we don’t mean a specific person. We’re talking about numbers. And those numbers measure the affect of your designs. 


Tomorrow we will learn why measuring psychology isn’t about yes or no answers: The Probability of Interaction.