Cohort-authored reviews
6,953,460 reviews
Any five-star review by a cohort member.AMAZON 2023 · COMPLETED RESEARCH
Inspect the public-trace footprint.
Explore Gijs Overgoor and coauthors’ completed analysis of the Amazon Reviews 2023 archive, collected by McAuley Lab at UC San Diego. Every setting below opens saved research results.
Source: McAuley Lab’s Amazon Reviews 2023 dataset on Hugging Face ↗
SELECTED RESEARCH SCOPE
All five-star reviews
January 1–September 14, 2023 · full-release archive audit
Cohort entry count 10Minimum burst 5 reviews
The complete procedure includes all five-star reviews in the audit period, whether or not the purchase was marked verified.
Reviews in cohort bursts
3,770,922 reviews
Cohort-authored reviews with the selected minimum number of cohort reviews on the same product within 28 days before or after the review date.Reviews by recurring burst authors
2,871,510 reviews
Reviews in cohort bursts whose author appears in qualifying bursts on at least two distinct products.Five-star reviews
Used for the overall, entry-count, and ordering results. Categories use their own denominators.
Jan 1–Sep 14, 2023L0, L1, and L2 are nested footprints of public review structure. They are not additive and do not estimate confirmed fraud or an individual account’s fraud probability.
COHORT ENTRY COUNT
How the footprint changes.
The review scope and minimum burst size stay as selected above. Each row shows a saved result for a different cohort entry count.
| Entry count | L0 share | L1 share | L2 share |
|---|---|---|---|
| 2 | 79.9% | 47.0% | 31.7% |
| 5 | 66.2% | 37.9% | 26.9% |
| 10Selected | 43.4% | 23.5% | 17.9% |
| 14 | 10.9% | 5.1% | 4.9% |
| 18 | 7.0% | 2.8% | 2.7% |
| 20 | 5.3% | 1.9% | 1.9% |
| 30 | 1.4% | 0.2% | 0.2% |
L0: reviews authored by the cohort. L1: cohort reviews in bursts. L2: cohort-burst reviews by recurring authors. Bars use the same 0–100% scale.
ACROSS PRODUCT CATEGORIES
The footprint by category.
Alphabetical categories from the completed analysis. Each row uses its own five-star review denominator, under all five-star reviews.
| Category | Five-star reviews | L0 share | L1 share | L2 share |
|---|---|---|---|---|
| All Beauty | 8,375 | 38.5%3,222 reviews | 10.2%856 reviews | 7.7%647 reviews |
| Amazon Fashion | 20,486 | 40.0%8,197 reviews | 11.2%2,299 reviews | 8.9%1,832 reviews |
| Appliances | 79,030 | 36.2%28,596 reviews | 16.8%13,249 reviews | 12.9%10,221 reviews |
| Arts Crafts and Sewing | 313,701 | 38.2%119,778 reviews | 12.1%38,091 reviews | 11.1%34,748 reviews |
| Automotive | 691,415 | 33.2%229,519 reviews | 11.7%80,797 reviews | 9.2%63,762 reviews |
| Baby Products | 164,887 | 43.8%72,242 reviews | 23.6%38,866 reviews | 20.3%33,438 reviews |
| Beauty and Personal Care | 1,025,186 | 48.2%493,957 reviews | 29.5%302,750 reviews | 22.4%229,794 reviews |
| Books | 471,637 | 29.6%139,373 reviews | 8.9%41,750 reviews | 7.2%34,111 reviews |
| CDs and Vinyl | 36,312 | 25.8%9,385 reviews | 1.4%510 reviews | 1.1%417 reviews |
| Cell Phones and Accessories | 589,592 | 46.4%273,555 reviews | 30.1%177,623 reviews | 20.7%122,257 reviews |
| Clothing Shoes and Jewelry | 2,266,901 | 43.2%979,556 reviews | 23.7%537,553 reviews | 18.0%408,421 reviews |
| Digital Music | 2,890 | 21.9%634 reviews | 0.2%6 reviews | 0.2%6 reviews |
| Electronics | 1,176,225 | 47.9%563,433 reviews | 32.3%380,150 reviews | 21.2%249,498 reviews |
| Gift Cards | 4,745 | 79.5%3,774 reviews | 71.1%3,373 reviews | 52.3%2,484 reviews |
| Grocery and Gourmet Food | 467,461 | 42.4%198,244 reviews | 21.0%97,966 reviews | 16.6%77,440 reviews |
| Handmade Products | 35,212 | 31.9%11,220 reviews | 9.4%3,321 reviews | 8.1%2,846 reviews |
| Health and Household | 963,355 | 50.0%481,349 reviews | 33.0%317,515 reviews | 23.6%227,643 reviews |
| Health and Personal Care | 6,593 | 38.6%2,544 reviews | 10.0%660 reviews | 9.2%606 reviews |
| Home and Kitchen | 2,530,525 | 45.5%1,151,358 reviews | 25.9%654,170 reviews | 20.2%509,910 reviews |
| Industrial and Scientific | 183,761 | 41.3%75,879 reviews | 18.4%33,823 reviews | 16.1%29,531 reviews |
| Kindle Store | 487,891 | 44.6%217,487 reviews | 24.5%119,361 reviews | 20.9%101,972 reviews |
| Magazine Subscriptions | 142 | 54.2%77 reviews | 0.0%0 reviews | 0.0%0 reviews |
| Movies and TV | 135,278 | 37.1%50,151 reviews | 11.9%16,083 reviews | 7.9%10,718 reviews |
| Musical Instruments | 83,422 | 34.7%28,943 reviews | 12.8%10,684 reviews | 10.9%9,099 reviews |
| Office Products | 439,412 | 42.5%186,619 reviews | 19.7%86,615 reviews | 16.9%74,191 reviews |
| Patio Lawn and Garden | 583,752 | 38.1%222,142 reviews | 18.0%105,341 reviews | 14.3%83,664 reviews |
| Pet Supplies | 590,714 | 48.3%285,221 reviews | 32.1%189,343 reviews | 22.6%133,335 reviews |
| Software | 15,731 | 30.9%4,863 reviews | 20.2%3,180 reviews | 10.1%1,593 reviews |
| Sports and Outdoors | 514,551 | 40.0%205,684 reviews | 18.5%95,195 reviews | 14.3%73,456 reviews |
| Subscription Boxes | 253 | 23.7%60 reviews | 0.0%0 reviews | 0.0%0 reviews |
| Tools and Home Improvement | 980,461 | 43.7%428,060 reviews | 22.7%222,611 reviews | 18.3%179,644 reviews |
| Toys and Games | 571,986 | 41.8%239,156 reviews | 17.4%99,328 reviews | 15.7%90,056 reviews |
| Unknown | 487,995 | 39.7%193,703 reviews | 15.1%73,918 reviews | 11.3%55,028 reviews |
| Video Games | 105,905 | 42.9%45,479 reviews | 22.6%23,935 reviews | 18.1%19,142 reviews |
SEARCH ORDER
Variation across completed orderings.
The research repeated the session ordering three times at cohort entry count 10 and minimum burst size 5. These are the observed ranges across those runs, not confidence intervals.
L0 share43.3454%–43.3880%
L1 share23.5102%–23.5369%
L2 share17.8894%–17.9078%
Inspect each completed ordering
| Ordering | L0 share | L1 share | L2 share |
|---|---|---|---|
| 1 · seed 61000 | 43.3622% | 23.5157% | 17.9069% |
| 2 · seed 62000 | 43.3880% | 23.5369% | 17.9078% |
| 3 · seed 63000 | 43.3454% | 23.5102% | 17.8894% |
RESEARCH AND DATA
Explore the findings and the research behind them.
Source archive: McAuley Lab’s Amazon Reviews 2023 on Hugging Face ↗. The release contains reviews from multiple years. The reported audit uses reviews dated January 1–September 14, 2023 across all 34 release categories, including Unknown.
Analysis: Gijs Overgoor and coauthors applied the paper’s method to that archive to calculate the findings shown here. The earlier 2019–2020 campaign dataset is a separate public resource:
Public research dataset ↗These are the paper’s existing archive results. This site does not accept online contributions or provide account-level historical membership checks. Use the investigator to collect and export a case locally.