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Silly Lullaby cover
global pct
35.9

Book

Silly Lullaby

Two parallel scores from 5 calibrated reviewers and 5 raw-average reviewers.

35.9%
Z · Global
35.9%
Z · Cohort
27.4%
Raw · Global
27.4%
Raw · Cohort
Two scores · one item
Z-normalized · global
35.9
Z-normalized · cohortpublication decade
35.9
Raw average · global
27.4
Raw average · cohortpublication decade
27.4

Z-normalized corrects for reviewer bias (every reviewer re-centered onto their personal scale). Raw average uses simple mean across the broader pool including stddev=0 reviewers.

Where this book sits

0255075100

Z-normalized percentile · 5,285 ranked books

Mean reviewer z-score-0.031
Calibrated raw-mean rating4.60 /5
Broad raw-mean rating4.60 /5
90% CI-floor (z)-0.767
Reviewers (calibrated / broad)5 / 5

Summary

Silly Lullaby sits at the 36th z-normalized percentile across 5,285ranked books. The z-percentile differs from a raw star average because Rankquant subtracts each reviewer's personal baseline before aggregating — so a reader who rates everything 5 stars carries less weight than one who rates discerningly. Raw-average percentile is 27; the gap between the two measures how much bias-correction changes this title's standing. How percentiles are computed.

Pipeline applied to this title

The math, in this order

01
Z-score per reviewer

5 reviewers with rating variance re-centered onto a personal z-scale.

02
Aggregate

Mean z = -0.031. Broad raw mean = 4.60/5.

03
CI-floor

90% CI-floor = -0.767. Thin samples penalized.

04
ECDF percentile

Global 35.9. Z-track and raw-track ranked separately.

Similar percentile

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