Evaluation & Redesign · A/B Testing

A cluttered campus booking tool, rebuilt around real evidence

The only one of my projects built on a live, in-use system, so it was an evaluation problem before it was a design one. I combined heuristic evaluation, usability testing, and A/B testing to diagnose exactly why room booking was slow, then turned that evidence into a measurably faster redesign.

What this shows UX evaluation & research: heuristic analysis, usability testing, A/B testing, data analysis
Context Course Project · Team of 3 (I led evaluation & redesign)
Timeline 4 weeks · 2025

In this project, I...

  • Treated a high-traffic university booking system as an evaluation problem first, diagnosing where it failed before designing anything
  • Ran a 3-evaluator heuristic evaluation against Nielsen's heuristics, scoring each issue on a 1–4 severity scale to prioritize what mattered
  • Triangulated those findings with task-based usability testing (think-aloud + post-session interviews) to separate real blockers from noise
  • Designed and ran A/B testing with 16 participants across 5 groups, analyzing completion time, task success rate, and preference
  • Translated the evidence into a redesign that cut average task time by 53.8 seconds, with 100% of testers preferring it

How I evaluated the system

I made measuring the original system the first step of the process. Before designing anything, I ran three methods to pin down where it actually broke: heuristic evaluation, usability testing, and A/B testing.

1

Heuristic evaluation

3 evaluators · 1–4 severity scale

Audited the live system against Nielsen's and Norman's principles, then ranked every issue by severity.

2

Usability testing

Think-aloud · post-session interview

Task-based sessions surfaced what tripped people up, and the interviews captured why.

3

A/B testing

16 participants · 5 groups

Compared legacy against the redesign on time, success, and preference.

The problems I found

01

Static Table Search

Availability was buried in a static table, forcing users to scan manually, row by row, for an open room.

Legacy availability shown as a dense static table
02

Navigation & Data-Reset Bug

Switching between campus buildings reset the date to the current day, forcing users to repeatedly re-enter their search criteria.

Building switch resetting the selected date
03

Weak Signifiers

Primary action buttons were too small and low-contrast to be noticed, so users missed the next step.

Low-contrast primary action button

Wireframes built to test the fixes

For each problem I found, I designed a mid-fidelity wireframe of the fix, then put it in front of users to test. The static table became a requirements-driven search, so I could measure whether the new flow actually performed better than the original.

Mid-fidelity wireframe overview

Designing the A/B test & analyzing the data

I set up a controlled comparison: the legacy interface (A) against my redesigned flow (B), run with 16 participants split across 5 groups. Rather than rely on a single number, I measured three dimensions: how long the task took, whether people completed it successfully, and which version they preferred. That way efficiency, effectiveness, and satisfaction each had evidence behind it.

−53.8s
Average task time saved per booking on the redesigned flow, the efficiency measure
4 / 5
Groups found filter-based discovery more intuitive than the static table, the preference measure
100%
Of testers preferred the redesign overall, and every one completed the task faster

I visualized each dimension so the pattern was legible at a glance rather than buried in a spreadsheet: preference as a distribution, completion time as a direct A-vs-B comparison, and task success rate across both versions.

01

Preference distribution

Four of five groups favored requirements-based discovery over manual table scanning. A clear majority, not a marginal edge.

Pie chart of filter-based vs static-table preference
02

Completion time, A vs B

A direct comparison of task time on the legacy interface against the redesign confirmed the 53.8-second average saving.

A/B test completion time comparison table
03

Task success rate

Tracking successful completions and errors across both versions showed the redesign didn't just feel faster. People failed the task less often.

Task success rate and error rate across legacy and redesign

Where the numbers needed the interview to explain them

One result didn't fit the "redesign wins" story: a new "Waitlist" feature for peak demand confused 3 of 5 groups. The quantitative data flagged the friction, but it was the post-session interviews that explained it. The problem wasn't the concept, it was the button wording. That's exactly why I paired methods: the numbers told me where to look, the interviews told me why, and the fix turned out to be microcopy, not a redesign.

Waitlist notification button UI tested with participants

From evidence to the final design

Every change below traces back to a specific piece of evidence: a severity-ranked heuristic issue, a tested behavior, or an A/B result. Nothing here is a guess.

01

Requirements-Based Recommendations

Fixes Problem 01. Replaced manual table scanning with smart recommendations. Users input their needs and the system instantly surfaces relevant rooms.

Automated requirements-based search
02

Persistent Filters

Fixes Problem 02. Resolved the data-reset bug so filter criteria and search progress now persist across screens. No more re-entering data.

Persistent filters and seamless navigation
03

Clearer Signifiers & Layout

Fixes Problem 03. Larger primary buttons, stronger contrast, and more breathing room make the next action obvious at a glance.

Enhanced visibility and breathing room
04

Optimized Microcopy

Addresses the A/B finding. Rewrote button labels and feedback to eliminate the waitlist phrasing confusion testers ran into.

Optimized microcopy and waitlist feature

Impact & what I took away

The outcome: a redesign that cut average task time by 53.8 seconds and was preferred by 100% of testers, a measurable improvement to a tool thousands of students rely on.

The lesson: A/B testing surfaced a need I hadn't designed for. I'd optimized single-room booking, but users actually needed to chain multiple rooms together to cover a continuous time slot. That reframed efficiency for me. It isn't only speed and simplicity, it's flexibility in messy, real-world situations. On the next product, this is exactly the kind of hidden requirement I now design to catch early, before it shows up in testing.

More than the redesign itself, this project is where I learned to trust a structured evaluation process over instinct: to combine expert review, observed behavior, and quantitative testing so that every design decision can point back to evidence. That's the analytical discipline I bring to a product team.