You may not know the term “parallax scrolling,” but you’ve probably seen it in action. In the past couple years, parallax has become perhaps the most popular site design tool out there, embraced by commercial products and (largely thanks to “ Snow Fall ” from the New York Times) mainstream media alike. The effect occurs when various page elements move at different speeds, creating a sense of animation and a heightened interactive experience (examples below). It’s a step away from pragmatism and functionality toward novelty and visual appeal.

Whether that step takes web design in the right or wrong direction has become a topic of considerable debate. The parallax style has excited web developers and inspired any number of hype lists. It’s also triggered a backlash among critics who feel its bells-and-whistles approach detracts from actual content. Pitchfork creative director Michael Renaud recently told the Atlantic Wire he expects people to “tire” of the trend within a year or two.

The parallax site was only superior in one sense. It was fun.

What the discussion has lacked so far is much evidence from web users themselves. That’s the first thing Dede Frederick noticed when he decided to study parallax scrolling for a graduate project at Purdue University. Frederick, who’s currently getting a doctorate in web design, scoured the literature for studies of parallax–and found none. “It looks nice, and I like it,” says Frederick of parallax, “but I couldn’t find much [research] to start me off.”

So Frederick set up a study of his own. He designed two hotel websites similar in every way, from content to color scheme, except that one featured parallax scrolling and one did not. Frederick then intercepted 86 people in the lobby of the Stewart Center, a main gathering point on Purdue’s campus, and brought them to a computer where they engaged with either the standard site or the parallax site (screenshot below).

The test itself didn’t last very long. Participants spent a few minutes getting familiar with whichever site they’d been assigned. They entered demographic information into a web form. (They all experienced a site error, too, because Frederick wanted to incorporate the unruly nature of web use.) They made a hotel reservation. Finally they rated the site on a questionnaire crafted from prior web research.

Frederick’s survey focused on five areas of the user experience: usability, enjoyment, fun, satisfaction, and visual appeal. (Enjoyment and fun, while ostensibly similar metrics, differed in that a site like IMDb can be enjoyable without being fun in the way a video game site might be.) Before he tallied the results, Frederick was convinced the parallax site would blow its opponent away.

“I’ve read from many blogs how people say it’s going to attract users and create so much of a better user experience,” Frederick tells Co.Design. “I thought it was going to be superior to a typical website in every aspect.”