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Grandma's Girl: Celebrate the Special Bond Between Granddaughter and Grandma cover
global pct
37.1

Book

Grandma's Girl: Celebrate the Special Bond Between Granddaughter and Grandma

Two parallel scores from 3 calibrated reviewers and 6 raw-average reviewers.

37.1%
Z · Global
37.1%
Z · Cohort
55.1%
Raw · Global
55.1%
Raw · Cohort
Two scores · one item
↓ crowd-elevated · 18-pt gap
Z-normalized · global
37.1
Z-normalized · cohortpublication decade
37.1
Raw average · global
55.1
Raw average · cohortpublication decade
55.1

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. The 18-point gap is the rating-inflation signature for this title — the casual crowd liked it more than discriminating reviewers (a classic inflation pattern).

Where this book sits

0255075100

Z-normalized percentile · 5,285 ranked books

Mean reviewer z-score-0.015
Calibrated raw-mean rating4.67 /5
Broad raw-mean rating4.83 /5
90% CI-floor (z)-0.965
Reviewers (calibrated / broad)3 / 6

Summary

Grandma's Girl: Celebrate the Special Bond Between Granddaughter and Grandma sits at the 37th 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 55; 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

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

02
Aggregate

Mean z = -0.015. Broad raw mean = 4.83/5.

03
CI-floor

90% CI-floor = -0.965. Thin samples penalized.

04
ECDF percentile

Global 37.1. Z-track and raw-track ranked separately.

Similar percentile

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