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Colorado Map (National Geographic Guide Map) cover
global pct
1.1

Book

Colorado Map (National Geographic Guide Map)

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

1.1%
Z · Global
1.1%
Z · Cohort
0.3%
Raw · Global
0.3%
Raw · Cohort
Two scores · one item
Z-normalized · global
1.1
Z-normalized · cohortpublication decade
1.1
Raw average · global
0.3
Raw average · cohortpublication decade
0.3

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-1.695
Calibrated raw-mean rating2.60 /5
Broad raw-mean rating2.60 /5
90% CI-floor (z)-2.430
Reviewers (calibrated / broad)5 / 5

Summary

Colorado Map (National Geographic Guide Map) sits at the 1th 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 0; 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 = -1.695. Broad raw mean = 2.60/5.

03
CI-floor

90% CI-floor = -2.430. Thin samples penalized.

04
ECDF percentile

Global 1.1. Z-track and raw-track ranked separately.

Similar percentile

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