What is majority-minority-change?

A tool for comparing county racial-composition data from two Census snapshots. It identifies counties that crossed a majority-minority threshold, meaning no single racial group forms a majority under the chosen measure.

Use it to compare county population fields across two years, optionally limit the analysis to a state, and identify counties that crossed the threshold.

It automates the comparison between two years and flags threshold changes instead of requiring manual calculations across separate files.

How amkessler/nicar2026_skills_in_codex_claude configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to amkessler/nicar2026_skills_in_codex_claude. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/amkessler/nicar2026_skills_in_codex_claude/main/.claude/skills/majority-minority-change/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/amkessler/nicar2026_skills_in_codex_claude

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/amkessler/nicar2026_skills_in_codex_claude/majority-minority-change/github.svg)](https://agentmods.dev/skills/amkessler/nicar2026_skills_in_codex_claude/majority-minority-change)

Your own site

<a href="https://agentmods.dev/skills/amkessler/nicar2026_skills_in_codex_claude/majority-minority-change"><img src="https://agentmods.dev/badge/skills/amkessler/nicar2026_skills_in_codex_claude/majority-minority-change/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/amkessler/nicar2026_skills_in_codex_claude/majority-minority-change"><img src="https://agentmods.dev/badge/skills/amkessler/nicar2026_skills_in_codex_claude/majority-minority-change.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 36 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 508 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00036	$0.00508
Opus 5.5	$0.00014	$0.00203
Sonnet 5.5	$0.00007	$0.00102
Haiku 4.5	$0.00004	$0.00051

Measured 2mo ago against content hash dcf8c6776f13, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

majority-minority-change scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/skills/majority-minority-change/SKILL.md · 49 lines

What it actually says

Majority Minority Change

Use this skill to compare county demographics across two years and flag threshold crossings.

Requirements

R with dplyr, readr, stringr, and jsonlite
Two local CSV files with county identifiers and required race/population fields
Bundled Census CSV snapshots for immediate use:
- skills/majority-minority-change/data/county_race_acs5_2010.csv
- skills/majority-minority-change/data/county_race_acs5_2020.csv
No API key required

Required Input Columns

Join keys available in both files:
- county_fips (preferred), or
- both state and county
Metrics in both files:
- total_population
- non_hispanic_white

Standard Workflow

Confirm start/end files and year labels.
- --state accepts full names or USPS abbreviations (for example, Georgia or GA).
- Default bundled files:
  - start: skills/majority-minority-change/data/county_race_acs5_2010.csv
  - end: skills/majority-minority-change/data/county_race_acs5_2020.csv
Review skills/majority-minority-change/references/DATA_SCHEMA.md for exact derived/output field names before downstream filtering or selecting columns.
- Expected output naming includes nonwhite_share_<year_label> and delta_nonwhite_share_pp.
Run script with optional state filter.
- Example: Rscript skills/majority-minority-change/scripts/analyze_majority_minority_change.R --input-start skills/majority-minority-change/data/county_race_acs5_2010.csv --input-end skills/majority-minority-change/data/county_race_acs5_2020.csv --start-label 2010 --end-label 2020
Review counties with largest percentage-point shifts and threshold crossings.

Output

Return:

non-white share in each year
percentage-point change
crossed_to_majority_minority
crossed_out_of_majority_minority

Files

What ships with it

5 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

2mo ago First seen · 49 lines · 36 tokens per session scan A dcf8c6776f13

Subscribe to this mod's changes

majority-minority-change is a skill published in the GitHub repository amkessler/nicar2026_skills_in_codex_claude (21 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 36 tokens to every session and 508 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Analytics and metrics

majority-minority-change next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
majority-minority-changeamkessler/nicar2026_skills_in_codex_claude	Skill	21	3mo ago	Apache-2.0	A	36	Claude Code
imagegenopenai/codex	Skill	133k	yesterday	Apache-2.0	A	113	Codex
playwright-climicrosoft/playwright	Skill	99k	yesterday	Apache-2.0	A	19	Claude Code
local-ai-agentsmicrosoft/ai-agents-for-beginners	Skill	79k	4d ago	MIT	A	200	Claude Code, Codex
systematic-debuggingobra/superpowers	Skill	313k	3d ago	MIT	A	21	Claude Code
next-cache-components-adoptionvercel/next.js	Skill	143k	today	MIT	A	95	Claude Code
next-partial-prefetching-adoptionvercel/next.js	Skill	143k	today	MIT	A	103	Claude Code

nicar2026_skills_in_codex_claude: Skill for Claude Code