Research

Repeated sampling enables GEO action by topic and prompt

Understanding how a large language model (LLM) typically talks about a category or brand is a challenge. The models are probabilistic, which means their responses vary even when a prompt stays the same.

AI marketing platforms disagree on how to solve this challenge. At Evertune, we repeat each prompt up to 100 times per model, amassing a meaningful sample size for every prompt. Other platforms argue that if you have enough unique prompts, a simple average visibility score of the entire prompt portfolio is sufficient after running each prompt only once.

For this experiment, we did both. Here's what we found.

Overall brand visibility

For our methodology faceoff, we ran 100 unique prompts about running shoes. The prompts were spread evenly across 10 topics - topics like “marathon training,” “budget picks,” “beginner runners,” etc.

When we ran prompts once each, Adidas appeared in 29% of 100 responses, with a margin of error of ±9 points. When we ran prompts 100 times each, Adidas again appeared in 29% of responses, but the margin of error shrank to ±1 point thanks to the sample size now reaching 10,000 responses.

So far, the methodologies agree: Adidas shows up about 29% of the time to prompts about running shoes. That certainly leaves room for improvement. What should Adidas do next?

Where should Adidas focus?

If Adidas wants a generative engine optimization (GEO) strategy to improve their visibility, upon which of the 10 topics should it focus its marketing time, energy and dollars?

When unique prompts are run once each, each topic has only 10 responses. Such a small sample size leaves room for response-to-response randomness to obscure meaningful signals. At 100 responses per unique prompt, each topic has a sample size of 1,000, enough data to overcome the problem of random noise.

The topic-level margin of error gets as high as ±31 points when prompts are repeated once each. It maxes out at ±3 points when prompts are repeated 100 times each.

Take “sustainable shoes” as an example. Asking each prompt once each tells Adidas that its visibility is probably between 19% and 81% (50% ±31 points). That’s not actionable. Asking each prompt 100 times tells Adidas that its visibility is probably between 51% and 57%. Now Adidas knows it has something to build on, and it has confidence that this is its 3rd-most-visible topic. 

Topic Margin of Error
ASKED ONCE · 10 RESPONSES PER TOPIC ASKED 100× · 1,000 RESPONSES PER TOPIC
TOPIC UNIQUE PROMPTS VISIBILITY MARGIN OF ERROR VISIBILITY MARGIN OF ERROR
Race-day shoes1090%±23 pts83%±2 pts
Sustainable shoes1050%±31 pts54%±3 pts
Marathon training1050%±31 pts51%±3 pts
Budget picks1050%±31 pts44%±3 pts
Everyday trainers1030%±26 pts22%±3 pts
Wide-fit shoes1020%±24 pts17%±2 pts
Beginner runners1010%±19 pts11%±2 pts
Cushioned long runs1010%±14 pts5%±1 pt
Trail running100%±12 pts4%±1 pt
Stability, flat feet100%±7 pts1%±1 pt
Overall10029%±9 pts29%±1 pt

Drilling down deeper

Adidas may now want to investigate its greatest strengths and weaknesses further by drilling down from topics to prompts. 

If it intends to double down on its greatest strength, “race-day shoes,” it would want to know if it is universally strong in this topic or if there are sub-topics within the topic in which its visibility differs. 

Similarly, it may want to investigate if “trail running” is really such a visibility laggard or if it simply tested the wrong prompts for this topic. Because LLMs are probabilistic, slight differences in prompts can have great effects, and the longer the list of unique prompts, the more likely prompts wander away from the topic they set out to measure.

If each prompt was sampled once, then prompt visibility is binary - either Adidas was mentioned or it wasn’t. If each prompt was sampled 100 times, prompt visibility is a percentage with a margin of error of ±10 points or less.

Only repeated samples of each prompt enable Adidas to investigate these questions and drill down to the prompt level.

Prompt Margin of Error
ASKED ONCE · 1 RESPONSE PER PROMPT ASKED 100× · 100 RESPONSES PER PROMPT
PROMPT RESULT MARGIN OF ERROR VISIBILITY MARGIN OF ERROR
Race-day shoes — 83% at topic level (±7 pts)
“What are the best carbon-plate racing shoes?”Mentioned±20 pts99%±2 pts
“Best super shoes for a marathon PR?”Mentioned±28 pts98%±3 pts
“Which shoes should I race a half marathon in?”Mentioned±28 pts98%±3 pts
“What’s the fastest marathon shoe right now?”Mentioned±34 pts97%±3 pts
“Which racing shoes have the best energy return?”Mentioned±34 pts97%±3 pts
“Best race shoes for midpack runners?”Mentioned±39 pts96%±4 pts
“Recommend a lightweight shoe for race day.”Mentioned±50 pts93%±5 pts
“Which racing flats are worth the money?”Mentioned±81 pts79%±8 pts
“Which carbon shoes are best for a 10k?”Mentioned±89 pts71%±9 pts
“Are super shoes worth it for a 4-hour marathoner?”No mention±34 pts3%±3 pts
Sustainable shoes — 54% at topic level (±10 pts)
“Best performance shoe with a low climate impact?”Mentioned±50 pts93%±5 pts
“Which running shoes use recycled materials?”Mentioned±53 pts92%±5 pts
“Which brands make carbon-neutral running shoes?”Mentioned±77 pts81%±8 pts
“What are the most sustainable running shoes?”Mentioned±83 pts77%±8 pts
“Which shoe brands are serious about sustainability?”Mentioned±93 pts66%±9 pts
“Most repairable or recyclable running shoes?”No mention±98 pts48%±10 pts
“Which eco running shoes actually perform?”No mention±97 pts42%±10 pts
“Recommend an eco-friendly running shoe.”No mention±79 pts20%±8 pts
“Best vegan running shoes?”No mention±59 pts10%±6 pts
“Best running shoes made with natural materials?”No mention±53 pts8%±5 pts
Marathon training — 51% at topic level (±10 pts)
“Which running shoes do marathoners actually race in?”Mentioned±20 pts99%±2 pts
“What are the best running shoes for marathon training?”Mentioned±39 pts96%±4 pts
“Best rotation of shoes for marathon prep?”Mentioned±68 pts86%±7 pts
“Which shoes hold up best over a 16-week marathon plan?”Mentioned±94 pts65%±9 pts
“What marathon shoes work for slower runners?”Mentioned±98 pts48%±10 pts
“What’s the best shoe to wear for a first marathon?”No mention±97 pts41%±10 pts
“What should I look for in a marathon training shoe?”No mention±93 pts34%±9 pts
“Which shoes should I do my 20-mile long runs in?”No mention±74 pts17%±7 pts
“Recommend a durable trainer for high-mileage marathon prep.”No mention±70 pts15%±7 pts
“Which trainers are best for back-to-back long runs?”No mention±56 pts9%±6 pts
Budget picks — 44% at topic level (±10 pts)
“Cheapest shoes that can handle marathon training?”Mentioned±64 pts88%±6 pts
“Best cheap running shoes that still last?”Mentioned±68 pts86%±7 pts
“Good running shoes for a student budget?”Mentioned±95 pts64%±9 pts
“Which budget shoes are good for beginners?”Mentioned±95 pts63%±10 pts
“Recommend a budget running shoe for daily use.”No mention±94 pts35%±9 pts
“What’s the best value running shoe right now?”No mention±92 pts32%±9 pts
“Are budget running shoes good enough for daily miles?”No mention±89 pts29%±9 pts
“What are the best running shoes under $100?”No mention±79 pts20%±8 pts
“Best running shoes under $80?”Mentioned±78 pts19%±8 pts
“Best last-year running shoes worth buying on sale?”No mention±0 pts0%±0 pts
Everyday trainers — 22% at topic level (±8 pts)
“What running shoe should I buy if I can only own one?”Mentioned±92 pts67%±9 pts
“What’s the best all-round daily running shoe?”Mentioned±98 pts46%±10 pts
“Best do-everything running shoe right now?”No mention±95 pts36%±9 pts
“What shoes are good for easy runs and daily miles?”Mentioned±79 pts20%±8 pts
“Which everyday running shoe is most versatile?”No mention±74 pts17%±7 pts
“Which daily trainer gives the best value per mile?”No mention±72 pts16%±7 pts
“What’s a reliable shoe for 30 miles a week?”No mention±62 pts11%±6 pts
“Which running shoe is best for daily 5ks?”No mention±39 pts4%±4 pts
“Best neutral daily running shoe?”No mention±28 pts2%±3 pts
“Recommend a comfortable everyday trainer.”No mention±28 pts2%±3 pts
Wide-fit shoes — 17% at topic level (±7 pts)
“Which brands make wide-fit running shoes?”Mentioned±76 pts82%±8 pts
“Which brand runs widest in running shoes?”No mention±92 pts32%±9 pts
“Which running shoes fit high-volume feet?”Mentioned±92 pts32%±9 pts
“Comfortable wide running shoes for beginners?”No mention±70 pts15%±7 pts
“What are the best running shoes for wide feet?”No mention±59 pts10%±6 pts
“Best wide toe-box shoes for road running?”No mention±20 pts1%±2 pts
“Recommend a roomy toe-box running shoe.”No mention±20 pts1%±2 pts
“What running shoes come in 2E or 4E widths?”No mention±20 pts1%±2 pts
“Best shoes for runners with bunions?”No mention±0 pts0%±0 pts
“What are the best extra-wide trail shoes?”No mention±0 pts0%±0 pts
Beginner runners — 11% at topic level (±6 pts)
“Best affordable shoes to start running in?”Mentioned±92 pts68%±9 pts
“Which running shoes are best for a 5k training plan?”No mention±77 pts19%±8 pts
“Best shoes for a couch-to-5k program?”No mention±50 pts7%±5 pts
“What’s a good starter shoe for jogging?”No mention±43 pts5%±4 pts
“What running shoes should a beginner buy?”No mention±39 pts4%±4 pts
“Recommend a first pair of running shoes.”No mention±34 pts3%±3 pts
“I’m new to running — what shoes do I need?”No mention±28 pts2%±3 pts
“What shoes help new runners avoid injury?”No mention±28 pts2%±3 pts
“How do I choose my first running shoes?”No mention±0 pts0%±0 pts
“What’s the most forgiving shoe for a new runner?”No mention±0 pts0%±0 pts
Cushioned long runs — 5% at topic level (±4 pts)
“Best cushioned running shoes for marathons”Mentioned±98 pts48%±10 pts
“Which plush trainers still feel stable?”No mention±28 pts2%±3 pts
“Best max-cushion shoes for long slow runs?”No mention±0 pts0%±0 pts
“Best soft shoes for high-mileage weeks?”No mention±0 pts0%±0 pts
“Most cushioned running shoe that isn’t mushy?”No mention±0 pts0%±0 pts
“Recommend a plush shoe for recovery runs.”No mention±0 pts0%±0 pts
“What are the most cushioned running shoes?”No mention±0 pts0%±0 pts
“What’s the best high-cushion trainer for heel strikers?”No mention±0 pts0%±0 pts
“Which max-cushion shoes are best for tired legs?”No mention±0 pts0%±0 pts
“Which shoes feel softest over 15+ miles?”No mention±0 pts0%±0 pts
Trail running — 4% at topic level (±4 pts)
“Best trail shoes for wet roots and rock?”No mention±88 pts28%±9 pts
“Best shoes for an ultramarathon on trails?”No mention±47 pts6%±5 pts
“What are the best trail running shoes?”No mention±28 pts2%±3 pts
“Most durable trail running shoes?”No mention±20 pts1%±2 pts
“Recommend trail shoes for rocky terrain.”No mention±20 pts1%±2 pts
“Which trail shoes work on hard-packed paths?”No mention±20 pts1%±2 pts
“Best waterproof trail runners for winter?”No mention±0 pts0%±0 pts
“What shoes for a first 50k trail race?”No mention±0 pts0%±0 pts
“What trail runners work for hiking too?”No mention±0 pts0%±0 pts
“Which shoes grip best on muddy trails?”No mention±0 pts0%±0 pts
Stability, flat feet — 1% at topic level (±2 pts)
“Which brand makes the best stability trainers?”No mention±66 pts13%±7 pts
“What shoes help prevent shin splints?”No mention±20 pts1%±2 pts
“Best running shoes to pair with orthotics?”No mention±0 pts0%±0 pts
“Best shoes for runners with fallen arches?”No mention±0 pts0%±0 pts
“Best supportive shoes for long shifts and runs?”No mention±0 pts0%±0 pts
“Recommend running shoes with strong arch support.”No mention±0 pts0%±0 pts
“What are the best running shoes for flat feet?”No mention±0 pts0%±0 pts
“What running shoes help with ankle stability?”No mention±0 pts0%±0 pts
“Which shoes correct mild overpronation?”No mention±0 pts0%±0 pts
“Which stability shoes help with overpronation?”No mention±0 pts0%±0 pts

Repeated sampling yields actionable insights

A wide array of prompts, each sample once, can get you a clear picture of a brand’s overall visibility. It can’t do more than that.

Asking a wide array of prompts and repeatedly sampling each prompt gives you both breadth and depth. You get a clear picture of a brand’s overall visibility, and you can drill down to find topic and prompt level insights, the very insights you need to take GEO action.

Methodology

At Evertune, we track thousands of brands across LLMs by running millions of prompts a day. For this analysis, we ran 10,000 prompts on ChatGPT about running shoes, divided evenly across 10 topics. We compared the results of our full 10,000 responses to a sample of 100 responses from within these responses to compare our methodology to that of other GEO platforms.

Evertune is the AI marketing platform for brands that want to own the AI customer journey. Evertune analyzes prompt responses at scale across all major LLMs, ChatGPT, Claude, Gemini, AI Overviews and more, to deliver statistically significant visibility data, then closes the loop with tools to act on it: website optimization, data-driven content creation, most influential sources, and paid activation through affiliate and programmatic AI retargeting partners. Where most tools tell you where you stand, Evertune tells you what to do about it. Founded by early executives of The Trade Desk and backed by $20M from leading investors.‍