New working paper · Can advertising fund free AI? Evidence from ChatGPT's international advertising rollout → Paid ChatGPT visits returned about a third of a paid-search visit's value Organic ChatGPT referrals fell by about 6 to 8% after ads arrived; conversion held
ecommerceresearch.org Available for advisory & talks

§ Research / about

We study how AI assistants change the way people buy online

01 · Who we are

Christian Schulze

Frankfurt School of Finance & Management

Christian Schulze is Associate Professor of Marketing at Frankfurt School of Finance & Management. His research focuses on customer strategy, e-commerce, digital marketing and the role of AI in commerce.

Google Scholar ↗Frankfurt School ↗Website ↗Email

Maximilian Kaiser

WU Vienna · Grips Intelligence

Maximilian Kaiser is Assistant Professor in the Department of Business Analytics and Decision Sciences at WU Vienna, a lecturer at the UCLA Anderson School of Management and scientific advisor to Grips Intelligence. He works on digital commerce and large-scale web analytics.

Google Scholar ↗Website ↗Email

02 · Our research

Our papers so far

No. 001Marketing Science 2026 ChatGPT Referrals to E-Commerce Websites Converts above paid social, below all other channels Read the summary No. 002Working paper · 2026 Can Advertising Fund Free AI? A paid ChatGPT visit earns a third of a paid-search visit · Ads introduction hurt organic referral volume Read the summary

03 · Our data

What websites record, not what people say

Our studies use first-party Google Analytics data from the websites of thousands of companies, provided by Grips Intelligence: which channel brought each visitor, and whether and how much that visitor bought. This shows how customers actually behave, instead of what they say in surveys. For us, e-commerce includes every company that sells goods or services on its website, to consumers (B2C) and to businesses (B2B).

Grips Intelligence provides the data free of charge and has no role in our research questions, design, analysis or writing. Maximilian Kaiser serves as its scientific advisor. The identities of the companies in the data remain confidential.

04 · Working with us

Available for advisory work and talks

We help management teams make decisions with evidence from thousands of companies' websites rather than with vendor claims. Typical questions we work on:

Whether ChatGPT and other AI assistants are worth investing in as a sales channel for your company, and how to read AI referrals in your analytics Whether to buy ads in ChatGPT and other AI assistants, and at what price they would pay off against paid search Benchmarking: how your channels compare with those of thousands of other companies, and what your own data means against that bigger picture
Christian Schulze on stage at the GEO Know-How conference, with the audience in front
GEO Know-How Konferenz, October 2026 · Photo: Laura Hoffmann
Christian Schulze giving the keynote at the Frankfurt School New Year's Reception
Frankfurt School New Year's Reception, January 2026
Christian Schulze on stage in front of the full auditorium of the Hessischer Kreis
Hessischer Kreis, January 2026 · Photo: Erik Löffler

We are available for advisory work with companies, and for keynotes and talks at conferences and company events.

Ask about advisory work →Ask about a keynote →

05 · Using our work

Quote the papers, use the slides

Every paper page has the full text, the citation and slides for teaching. When you report on a finding, please quote the numbers from the paper or from its page here, and link the page, so that your readers can check them.

Journalists can reach us at christian@ecommerceresearch.org.