PBYMT Detachable Passenger Backrest Fit for Harley Touring, Quick Release Sissy Bar Compatible with Harley Davidson Street Glide Road Glide Road King Electra Glide Ultra Limited 2009-2024 (Chrome)

We compare the reviewers of this product against every other product those same people reviewed. Each review is scored relative to the reviewer's own baseline — four stars from someone who hands out fives means something very different from four stars from someone who rarely goes above three.

Those calibrated scores are then averaged, one value per reviewer, each counting equally. The percentile is where that average falls among every product we score.

Reviewer calibration needs reviewers who rated more than one product, so it covers the part of the catalog where that overlap exists, not the whole of it.

Global percentile

Where PBYMT Detachable Passenger Backrest Fit for Harley Touring, Quick Release Sissy Bar Compatible with Harley Davidson Street Glide Road Glide Road King Electra Glide Ultra Limited 2009-2024 (Chrome) lands against every product we rank.

In-cohort percentile

The same comparison narrowed to its cohort — the other ranked products in the same category, so a kitchen gadget is judged against kitchen gadgets rather than against headphones. Ranked against Automotive (223,857 products).

AI-adjusted percentile

The same reviewer-normalized score, corrected for how much confidence the sample supports: thin samples are pulled toward the corpus average. Each product keeps the share n / (n + 53) of its measured distance from the average, where n is its calibrated-reviewer count, and the result is ranked on the same scale as the global percentile.53 is the median sample size across everything we rank. Here n is 4.