--- name: brycewang-stanford/aer-introduction source: https://app.decimal.ai/s/brycewang-stanford-aer-introduction@1/SKILL.md source_sha256: fc43cf4546ec --- # AER Introduction ## Overview The introduction is the **only** part of the paper most editors read in full. Top-5 desk rejection decisions are typically made on pages 1-3. This skill produces an introduction that survives that filter and an abstract that fits AER's 100-word constraint. Two non-negotiable AER formatting facts: 1. **No "Introduction" heading.** The introductory section is unlabeled and begins immediately after the title and abstract. 2. **Abstract ≤ 100 words.** Roughly 4-5 sentences. The AER Style Guide states the abstract "must not exceed 100 words"; an over-length abstract is flagged in editorial screening and returned for correction. ## When to Use - Drafting an introduction from scratch - Rewriting an introduction that drew a desk rejection - Compressing a 250-word working-paper abstract to AER's 100-word limit - The introduction is over 3 typeset pages and needs surgery - The user has results but cannot explain *why they matter* in one paragraph ## The Five-Paragraph Formula (Keith Head) Every AER-style introduction has exactly five components, in this order: ### Paragraph 1 — The Hook Open with one of: - **Y matters.** Welfare consequences, magnitudes, policy stakes. - **Y is puzzling.** A stylized fact existing theory cannot explain. - **Y is controversial.** Two camps disagree; new evidence resolves the question. - **Y is big.** A first-order phenomenon (the service sector, urban inequality, the trade balance). Two to three sentences. Cite **one** number that anchors the magnitude. Do not yet name the paper's contribution. ### Paragraph 2 — The Question State exactly what this paper does: ``` This paper [estimates / documents / characterizes] [the causal effect of X on Y / the response of Y to shock S / the distribution of Y in setting D]. ``` One paragraph. Define the unit of observation, the outcome, and the variation that identifies the answer. Avoid the word "we" if possible; use "this paper." ### Paragraph 3 — The Identification (or the Model) Empirical papers: name the identification strategy in one sentence, then explain in 1-2 paragraphs what variation drives identification and why the parallel trends / exclusion / smoothness assumption is credible *in this setting*. Theory papers: name the modeling discipline — what's tractable, what's general, what the comparative statics give you. This paragraph is where desk rejection happens. Editors check whether the method matches the claim. If you write "we examine the relationship between X and Y" while using OLS with controls, the paper is desk-rejected for methodology mismatch. ### Paragraph 4 — The Antecedents and Value-Added Often the *single most important paragraph for surviving referee review*. Two halves: **Antecedents (1-2 paragraphs).** Position the paper relative to its 3-6 closest published predecessors. Be specific: cite by author-year, identify what each did, and what each missed. **Value-added (1 paragraph or 3 bullet points).** State approximately **three** contributions relative to the antecedents. These are the sentences the referee will quote in their report. Each contribution should make sense only in light of the prior work — otherwise it belongs in the Question paragraph. Avoid: - "To the best of our knowledge, this is the first paper to ..." (unverifiable, often false) - "We contribute to the literature on X" (vacuous unless you say how) - Padding the contribution list past four items ### Paragraph 5 — The Roadmap One short paragraph. "Section I describes the data. Section II presents the empirical strategy. Section III reports results. Section IV explores mechanisms. Section V concludes." (AER numbers sections with Roman numerals; the introduction is unnumbered.) Some AER authors omit the roadmap entirely. Acceptable for short papers (AER: Insights). Required for full-length AER. ## The 100-Word Abstract AER abstracts are **100 words maximum**, including all numbers. The high-impact pattern allocates word budget as: | Function | Sentences | Words | |-----------------------------------|-----------|-------| | Question or setting | 1 | 15-20 | | Method / data / identification | 1 | 15-20 | | Main quantitative result | 1-2 | 30-40 | | Implication | 1 | 15-20 | **Allocate the most words to results.** Resist motivation-heavy abstracts — that is what the introduction's first paragraph is for. High-citation AER abstracts dedicate three of four sentences to findings. ### Abstract Template ``` [Setting and question — 1 sentence]. [Data and identification — 1 sentence]. [Main result with magnitude and sign — 1-2 sentences]. [Implication — 1 sentence]. ``` ### Word-Count Discipline If the draft is over 100 words: 1. Delete every adjective that does not change the result 2. Replace clauses with semicolons 3. Drop the implication sentence — the introduction handles it 4. Replace "we find that ... " with active "X raises Y by Z%" 5. Numbers count as one word each; don't burn budget on "approximately" ## AER-Specific Formatting - **No "Introduction" heading.** Begin the introductory material immediately after the abstract. - **No vertical space markup.** Use `\section` and `\subsection`; do not insert `\vspace` or `\bigskip`. - **Footnotes, not endnotes.** Inline citations use `\cite{}` (author-year), not numbered references. - **Style emphasis sparingly.** No `\textbf` for emphasis in body text — italics only, rarely. - **Sections use Roman numerals.** Per the AER Style Guide, major sections are numbered with Roman numerals (I., II., III.) and subsections with capital letters (A., B., C.). The introduction itself receives **no number and no heading** — the first *numbered* section is the one after it (e.g. "I. Data"). In LaTeX, switch the numbering with `\renewcommand{\thesection}{\Roman{section}}` or use the AEA sample article class, which does this for you. ## Anti-Patterns - Three-page introduction that never names the identification strategy → desk reject - Five contributions in the value-added paragraph, one of them weak → referee picks the weak one - Abstract with 130 words after a "minor tweak" → editor bounces submission - Hook paragraph that pitches a methods contribution when the paper is empirical (or vice versa) - Burying the magnitude of the main result until section 4 - Lit review that runs for 2 pages and does not say what *this* paper adds ## Repository Resources Bundled with the installed skill, no repository checkout needed --- read it before the repo resources below: - `references/intro-template.md` --- Keith Head five-paragraph templates plus the 100-word abstract recipe When working from the AER-skills repository or plugin bundle, read `examples/intro-example.md` only when the user asks for a model introduction, a concrete before/after rewrite, or abstract compression. Sentence-level prose rules shared with the body sections live in `docs/style-guide.md`; the antecedents paragraph consumes the map built by `skills/aer-literature/SKILL.md`. Draft the introduction **after** the body sections exist (`skills/aer-paper-body/SKILL.md`) — the introduction summarizes a paper, it does not promise one. ## Pre-Handoff Gate Ship the introduction only when **all** are true: - [ ] Abstract ≤ 100 words by actual word count, with most words spent on the result - [ ] All five paragraphs present in order — Hook, Question, Identification, Antecedents+Value, Roadmap - [ ] Identification strategy named within pages 1-3, not deferred to the methods section - [ ] Exactly three (max four) contributions, each meaningful only against the cited antecedents - [ ] No "Introduction" heading; the method claim matches the actual estimator - [ ] No banned phrasing — "to the best of our knowledge, the first to...", vacuous "we contribute to the literature on..." ## Handoff ```text ABSTRACT WORD COUNT: /100 INTRODUCTION PARAGRAPHS: Hook | Question | Identification | Antecedents+Value | Roadmap CONTRIBUTIONS LISTED: (target: 3, max 4) KILL SWITCHES: NEXT SKILL: ``` ## Reference Pattern A canonical AER-style intro architecture (paragraph-by-paragraph): 1. **Hook.** "The richest 1% of US households hold X% of wealth. This share has risen by Y percentage points since Z." 2. **Question.** "This paper estimates the causal effect of [policy] on top-wealth concentration using [variation]." 3. **Identification.** "We exploit [quasi-experiment]. The identifying assumption is [...]. We validate this by [pre-trends test / placebo / institutional argument]." 4. **Antecedents + value-added.** "Three prior papers (A 2019, B 2021, C 2023) study related questions. A used [method] but [limitation]. B documented [fact] but did not establish causation. C addressed causation but in [different setting]. This paper makes three contributions: first, [...]; second, [...]; third, [...]." 5. **Roadmap.** "Section I describes [...]. Section II [...]."