KPIs

By Morgan Housel

❓What is a KPI?

We all know data collection is important. UX designers track data to have benchmarks to prove growth. Data can support UX designer’s ideas and recommendations better than unsupported opinions.

In today’s climate, gathering data is rarely the challenge. The challenge is knowing exactly which numbers to track, and what exactly those numbers mean to an organization. That’s where KPI’s come in.

Key performance indicators are quantifiable measurements that help an organization define and track the progress toward its goals. They can vary from industry to industry, or business to business. Therefore, key performance indicators for a dog might be:

  • Miles walked
  • Pounds of food consumed
  • Number of tricks performed
  • Pats on head

While KPI’s for UX tends to include measurements such as:

  1. Task success rate
  2. Time on task
  3. User error rate

And a few qualitative KPI’s for UX may include:

  1. System Usability Scale
  2. Product Reaction Cards

While many of these may already seem familiar to you based on our lectures, I wanted to reiterate a few and sum them up once more.

Task Success Rate

Using scenario format, the researcher has a participant walk through a series of specific, articulate tasks, that have clear, well-defined end goals. If 8/10 users successfully complete a task, the task success rate is:

8/10 = 0.8 x 100 = 80%

The main disadvantage to this metric is that doesn’t tell the researcher why the participant failed. That’s why it’s worthwhile to pair this with the Think Aloud Protocol, and having a dedicated notetaker jot down errors.

Time on Task

Time on task is the amount of time it takes for a user to complete a task. Usually, time is converted into seconds. Since time is a proportion, calculate the geometric mean per task rather than use the standard old mean or average you’re used to from match class.

User Error Rate

User error rate is a little more tricky to measure, and there’s a few ways to go about calculating this rate.

For the purposes of this class, we’ll calculate the error rate as follows: Number of errors / total numbers of error opportunities.

For example, if five out of 10 users enter their security question incorrectly in form field. The error occurrence rate is calculated like this:

5/10 = 0.05 x 10 = 50%

System Usability Scale

Originally created by John Brooke in 1986, the System Usability scale is a speedy and efficient way to measure usability. This questionnaire features 10 questions with Likert scale responses; from strongly agree to strongly disagree.

  1. I think that I would like to use this system frequently.
  2. I found the system unnecessarily complex.
  3. I thought the system was easy to use.
  4. I think that I would need the support of a technical person to be able to use this system.
  5. I found the various functions in this system were well integrated.
  6. I thought there was too much inconsistency in this system.
  7. I would imagine that most people would learn to use this system very quickly.
  8. I found the system very cumbersome to use.
  9. I felt very confident using the system.
  10. I needed to learn a lot of things before I could get going with this system.

Follow instructions in the slides to calculate and understand results.

Product Reaction Cards

Created by Microsoft, Product Reaction Cards are designed to gauge the intangible aspect of user experience: people’s perception of a product. There are 118 cards, with 60% of the cards being positive words and 40% being negative or neutral words. Product reaction cards are more than just asking people to pick the top five cards they feel describe their experience with a product: It’s a way to ask why people think that.