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Tigers (National Geographic Kids Readers, Level 2) cover
global pct
75.6

Book

Tigers (National Geographic Kids Readers, Level 2)

Two parallel scores from 3 calibrated reviewers and 5 raw-average reviewers.

75.6%
Z · Global
75.6%
Z · Cohort
83.1%
Raw · Global
83.1%
Raw · Cohort
Two scores · one item
Z-normalized · global
75.6
Z-normalized · cohortpublication decade
75.6
Raw average · global
83.1
Raw average · cohortpublication decade
83.1

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.

Where this book sits

0255075100

Z-normalized percentile · 5,285 ranked books

Mean reviewer z-score+0.396
Calibrated raw-mean rating5.00 /5
Broad raw-mean rating5.00 /5
90% CI-floor (z)-0.553
Reviewers (calibrated / broad)3 / 5

Summary

Tigers (National Geographic Kids Readers, Level 2) sits at the 76th 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 83; 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 = +0.396. Broad raw mean = 5.00/5.

03
CI-floor

90% CI-floor = -0.553. Thin samples penalized.

04
ECDF percentile

Global 75.6. Z-track and raw-track ranked separately.

Similar percentile

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