gini (Gini) coefficient

Is "Gini coefficient" correct in your sentence? Use the quick rule below, then copy the ready-to-use rewrites for work, school, and casual contexts.

Focus on three simple checks and a few fast replacements to fix most errors immediately.

Quick answer

Write the term as Gini coefficient in running text: capital G for the eponym Corrado Gini, and lowercase c in coefficient unless title-case or sentence-start rules require otherwise.

Correct (sentence case): Gini coefficient
Wrong in sentence: gini coefficient, Gini Coefficient (mid-sentence unless your style uses title case), GINI coefficient
Adjectival use: prefer Gini-based rather than Gini-coefficient-based

Core rule (short)

Gini is an eponym: treat it like a proper name and capitalize it. Coefficient is a generic noun and stays lowercase in sentence case.

Apply normal sentence-start or title-case rules when the phrase begins a sentence or appears in a heading.

Eponym → capitalized: Gini
Generic noun → lowercase in sentence case: coefficient
Title-case headings may show: Gini Coefficient (if your style guide requires)

Grammar and small-format rules (hyphenation, spacing, plurals, abbreviations)

Keep one space between words, spell out "coefficient" in formal writing, and avoid awkward hyphen chains. When the phrase modifies a noun, use Gini-based instead of Gini-coefficient-based.

Noun phrase: the Gini coefficient (no hyphen)
Adjectival: a Gini-based indicator (preferred)
Plural: Gini coefficients
Abbreviations: define on first use - Gini coefficient (GC) - and avoid G alone

Wrong: Gini-coefficient estimate recommends two decimals.
Right: Gini-based estimate recommends two decimals.
Wrong: Gini Coeff.
Right: Gini coefficient
Wrong: GINI coefficient
Right: Gini coefficient

Real usage: copyable examples for work, school, and casual contexts

Use the suggested sentences as-is or adapt them to fit tone and audience.

Work: Please add the national Gini coefficient (0.41 in 2022) to slide 4 and include a one-sentence interpretation.
Work: We used the Gini coefficient to compare income inequality across our target regions; see Table 2 for values.
Work: Report Gini coefficients with three decimal places and include the calculation method in the appendix.
School: In the essay, discuss how the Gini coefficient changes under progressive taxation.
School: Problem set: calculate the Gini coefficient for the income distribution in Table A and compare it year over year.
School: The literature shows a correlation between GDP per capita and the Gini coefficient in some regions; cite sources accordingly.
Casual: I read that country's Gini coefficient is really high-any idea why?
Casual: If the Gini coefficient goes up, does that mean things are getting less equal?
Casual: What's the Gini coefficient for our city-quick check online?

Common wrong/right pairs (quick replace list)

Copy these pairs into a style guide or find-and-replace list for faster editing.

Replace all-lowercase 'gini' with 'Gini' when used as a name.
Replace 'Gini Coefficient' with 'Gini coefficient' in running text (unless title-case).
Replace 'Gini-coefficient-based' with 'Gini-based' for clarity.

Wrong: gini coefficient -
Right: Gini coefficient
Wrong: Gini Coefficient (mid-sentence) -
Right: Gini coefficient
Wrong: GINI index -
Right: Gini index
Wrong: Gini Coeff. -
Right: Gini coefficient
Wrong: gini index -
Right: Gini index
Wrong: Gini-coefficient-based -
Right: Gini-based

Fix-your-sentence: checklist plus copy-ready rewrites

Three-step checklist: (1) Capitalize Gini. (2) Keep coefficient lowercase in sentence case. (3) Use Gini-based for modifiers and define abbreviations.

Common bad snippets with tight rewrites you can paste directly.

Checklist: Capitalize Gini → Lowercase coefficient → Use Gini-based for modifiers → Define abbreviations.
If a phrase starts the sentence, consider moving it later to avoid title-case confusion.

Rewrite:
Wrong: the gini coefficient for this city rose sharply.
Rewrite: The Gini coefficient for this city rose sharply.
Rewrite:
Wrong: Gini Coefficient increased from 0.30 to 0.34.
Rewrite: The Gini coefficient increased from 0.30 to 0.34.
Rewrite:
Wrong: we saw a high gini.
Rewrite: We observed a high Gini coefficient.
Rewrite: Wrong (work): include Gini Coefficient in slide.
Rewrite: Please include the Gini coefficient on slide 3 with a brief note on calculation.
Rewrite: Wrong (school): compute the gini.
Rewrite: Compute the Gini coefficient for the given distribution.
Rewrite: Wrong (casual tweet): country has high gini.
Rewrite: That country has a high Gini coefficient.

Try your own sentence

Test the whole sentence, not just the phrase. Context often clarifies whether to use title case or sentence case.

Memory trick (one-liner you can remember)

Think: Gini = a person (Corrado) → name = capitalized; coefficient = a thing → lowercase.

Mini-mnemonic: "Gini is a name; coefficient is a thing."

If it feels like a person, capitalize it. If it's descriptive, lowercase it.
When editing fast, search for " gini " and "Gini Coefficient" and apply the rule.

Similar mistakes to watch for

Other statistical names follow the same pattern: capitalize eponyms, lowercase generic nouns.

Pareto principle - correct: Pareto principle
Lorenz curve - correct: Lorenz curve
Bayes' theorem - correct: Bayes' theorem
Fisher information - correct: Fisher information
GDP per capita - correct: GDP per capita

Wrong: pareto principle -
Right: Pareto principle
Wrong: lorenz curve -
Right: Lorenz curve
Wrong: GDP Per Capita -
Right: GDP per capita

Titles, abbreviations, citations - headings and technical sections

In headings follow your title-style guide. In running text use sentence-case Gini coefficient. Be consistent in tables and figure labels.

Title-case heading (if required): Gini Coefficient
Table column: Gini coefficient (GC) - define GC in a note if used
Citations: use "the Gini coefficient" rather than "Gini's coefficient" unless quoting historical phrasing

Editor shortcuts: find/replace tips and automated checks

Use search-and-replace to catch common variants, but review headings and captions manually.

Find: " gini " → Replace: " Gini " (watch boundaries)
Find: "Gini Coefficient" in mid-sentence → Replace: "Gini coefficient"
Find: "Gini-coefficient" → Replace: "Gini-based" or "Gini coefficient" depending on meaning
Flag isolated "G" as an abbreviation and expand if ambiguous

Automation tip: Replace "Gini Coefficient" with "Gini coefficient" in body text but exclude headings.
Automation tip: Capitalize "gini" at sentence starts when appropriate.

FAQ

Should I write "Gini coefficient" or "Gini Coefficient" in a title?

Follow your title-style guide. In sentence-case body text use "Gini coefficient". In title case, "Gini Coefficient" is acceptable; be consistent across headings.

Is lowercase "gini" ever correct?

Lowercase "gini" may appear in informal chat or deliberate stylistic choices, but for published, graded, or professional writing use "Gini".

Can I abbreviate the Gini coefficient as "GC" or "G"?

Define abbreviations on first use: "Gini coefficient (GC)". Avoid "G" alone because it's ambiguous.

How should I write multiple items: "Gini coefficients" or "Gini Coefficients"?

Use "Gini coefficients" in sentence case. Capitalize only when the phrase appears in title case or starts a sentence.

Should I hyphenate when using it as an adjective?

Prefer "Gini-based" for modifiers. Avoid "Gini-coefficient-based" - it's clunky and harder to read.

Need a quick check?

Paste a sentence into a grammar tool that recognizes eponyms or run the find/replace patterns above. A short house rule - "Capitalize eponyms; lowercase generic nouns" - fixes most issues quickly.