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Leavey School of Business Santa Clara University
Department ofMarketing

Watch My Eyes

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Person Spotlight photo

How Internet Shoppers Search Information

As more and more people make purchasing decisions using the Internet, academics have begun to focus research on how people make those decisions. Savannah Wei Shi, assistant professor of marketing, has been specializing in using eye-tracking equipment to better understand the workings of e-commerce.

Shi is lead author (with Michel Wedel of the University of Maryland and Rik Pieters of the University of Tilburg) of the paper, “Information Acquisition During Online Decision-Making: A Model-Based Exploration Using Eye-Tracking Data,” which is published in the journal Management Science.


How products are positioned on a comparison page will influence the customer's decision-making strategies.


“Traditional process-tracing method, such as Information Display Board or Mouselab, focuses on more controlled and deliberate information search and choice process,” she says. “Eye-tracking data provide insights into how consumers rapidly acquire information in information-rich online environments in real life. We used eye-fixation to study the decision-making process in an online retailer website, to look at the factors that drive eye movement from one place to the other on a comparison page.” A comparison page, she explains, is one on which customers can compare products and attributes.

Eye-tracking experiments were conducted using state-of-the-art equipment at the University of Maryland, where Shi worked before coming to Santa Clara. Subjects in the experiment were asked to make a purchasing decision among several computer models with different attributes on a major computer website. Their eye movements were recorded unobtrusively.

Experiments were conducted on two monitors eight hours a day over a period of two weeks, with the average subject taking 10-15 minutes to compare several computers and reach a decision.

With the aid of the tracking equipment, Shi and her colleagues were able to identify eye fixations (brief moments when the eye is stopped at, and presumably drawing information from, a point on the page) and saccades, rapid jumps of the eye from point to point on the page.

Finally, the raw data were subjected to a mathematical formula developed by Shi and her colleagues to adjust for variables. For example, if a subject’s eye stops in one place for a few seconds, is it taking in information from that one place, or is the subject daydreaming about that night’s dinner? There’s no way to know for sure, but a good formula can assign probabilities that are likely to make the overall results more reliable.

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Data generated from the experiments showed that the decision-making process was faster, more complex, and less well-structured than previously believed. For example, one participant made a decision in 76 seconds, during which there were 140 combined eye fixations and saccades, nearly two per second.

The data showed that participants frequently switched strategies, often comparing two or three attributes or products before switching to another strategic approach. One result that jumped out from the data was that people more consistently sampled information that was closely grouped on the page and moved their eyes horizontally, across rows rather than down columns, and that such a search pattern was present regardless of horizontal or vertical presentation format.

A practical implication of that finding, Shi says, is that a company that wants to nudge customers toward a certain product would do well to set up the comparison page so that the attributes run horizontally and the products run vertically in columns. That way a customer can easily select one attribute (for example, the capacity of the computer’s hard drive) and scan from left to right to see how the model the company wants to promote compares with the others.

“Customers are comparing different sets of products online all the time, and we assume the customers to be rational,” she says. “How the company places the product on a comparison web page can influence the strategies customers use to make decisions.”

Nov 30, 2015
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