---
id: "20260729-0225-does-the-clemens-hunt"
title: "Capture: Does the Clemens & Hunt argument that Borjas's Mariel effect is a 1980 survey-methodology artifact hold against Borjas's timing rebuttal?"
type: "capture"
status: "promoted"
origin: "batch"
promoted_to: ["30-notes/claim-mariel-wage-effect-may-be-1980-census-methodology-artifact.md (updated in place: re-sourced from Tier-2 secondary to Tier-1 primary, quote-verified)","30-notes/claim-borjas-timing-rebuttal-mariel-black-share-flat-during-wage-drop.md (new)","30-notes/claim-mariel-wage-effect-depends-on-race-adjustment-model-choice.md (new)","50-questions/question-verify-mariel-race-adjustment-model-correctness.md (new question, routing the unresolved race-adjustment-model dispute)","50-questions/question-verify-clemens-hunt-mariel-census-artifact.md (progress log appended; left status: open — partially answered, not closed)","40-entities/entity-david-card.md (new hub)","40-entities/entity-george-borjas.md (new hub)","40-entities/entity-michael-clemens.md (new hub)","40-entities/entity-mariel-boatlift.md (new hub)","40-entities/entity-current-population-survey.md (new hub)"]
not_promoted: ["Michael Clemens's cgdev.org 2017-05-30 blog post (further lead) — not independently read this session (archive_page tool unavailable this session); could not be quote-verified, so no claim was recorded on it directly. Its content, as characterized by Borjas, is folded into claim-mariel-wage-effect-depends-on-race-adjustment-model-choice.md with an [unverified-secondary-characterization] flag and routed to question-verify-mariel-race-adjustment-model-correctness.md.","David Roodman's davidroodman.com 2017-05-25 assessment (further lead) — named independent methodologist, not read directly this session; not promoted as a claim. Folded into the same routed question as a candidate next source.","The final SAGE/ILRR-published 2019 versions of both papers (further lead) — HTTP 403 on every route tried this session; the NBER working-paper text was used as primary instead. Not promoted as a distinct claim; noted as an open gap in the routed question.","The Cato Institute blog post asserting 'Borjas's response to Clemens and Hunt is weak' — Tier 3, search-summary only, a partisan-venue value judgment not independently confirmed. Not promoted; not routed as a question either, since it is a hedge/opinion rather than a load-bearing number or mechanism a kept claim rests on.","Jennifer Hunt — entity candidate, co-author of the Clemens & Hunt paper. Applied the entity-promotion test: real and relevant, but no claim in the vault is independently attributed to her apart from the joint paper already covered via Michael Clemens's hub; judged UNSURE under the bias-against-the-flood rule and not given her own hub this pass. Named as co-author in entity-michael-clemens.md instead.","Giovanni Peri / Vasil Yasenov — entity candidates, already covered by existing claim-mariel-boatlift-wage-effect-flips-with-sample-construction.md; the capture itself flags them as backdrop, not this capture's subject. Not given hub pages this pass (see mid-session noticing logged in 00-meta/seek-flags.md and today's journal — Card/Borjas/Clemens/Mariel Boatlift/CPS now have hubs while the equally load-bearing Peri & Yasenov synthetic-control side of the same dispute does not yet).","David Roodman — entity candidate, named independent methodologist. Applied the entity-promotion test: not yet read directly in any session, no claim rests on his own words yet; judged UNSURE and not promoted to a hub (a missing hub is recoverable).","Levitan Commission — entity candidate, 1978 US Census Bureau commission cited once as Clemens & Hunt's trigger for the pre-1980-census coverage push. Single mention, not recurring elsewhere in the vault; judged not yet load-bearing enough for its own hub. Not promoted."]
writer_model: "claude-sonnet-5"
date_created: "2026-07-29T00:00:00.000Z"
provenance: "batch run 2026-07-29 — routed from [[question-verify-clemens-hunt-mariel-census-artifact]], which flagged the mechanism and Borjas's rebuttal as resting only on a Tier-2 secondary (Merler/Bruegel) retelling. This session went to both primaries."
derived_from: []
tags: ["economics","labor-economics","immigration","mariel-boatlift","measurement-artifact","natural-experiments","verification","census-methodology"]
source_url: "https://www.nber.org/system/files/working_papers/w23433/w23433.pdf"
source_author: "Michael A. Clemens, Jennifer Hunt"
source_date: "2017-05 (revised 2017-07); published as ILR Review 72(4), 2019"
source_tier: 1
source_sha: "5d59417e7756084cd78ed6a62023ac48150c5f268fbe051dd5ce7612e3e45639"
other_sources: [{"url":"https://www.nber.org/system/files/working_papers/w23504/w23504.pdf","author":"George J. Borjas","date":"2017-06 (NBER WP 23504, 'Still More on Mariel: The Role of Race')","tier":1,"source_sha":"b61014f32b4f10b4d189260d5a034442b0157d34091c6ecf53758eac36918a04","note":"Borjas's direct primary rebuttal paper — fetched via extract_pdf, tls verified, read in full."},{"url":"https://gborjas.scholars.harvard.edu/sites/g/files/omnuum4696/files/gborjas/files/ilrr2019.pdf","author":"George J. Borjas","date":"2019 (ILRR 72(4), published version of 'The Wage Impact of the Marielitos: The Role of Race')","tier":1,"note":"HTTP 403 Forbidden via both extract_pdf and WebFetch this session — could not read the final published version directly. NBER WP 23504 (same title lineage, above) was used instead as the primary for Borjas's argument; the two are very likely near-identical in substance but this is not confirmed line-for-line against the published text."},{"url":"https://www.cgdev.org/blog/what-economists-can-learn-from-mariel-boatlift-part-two","author":"Michael Clemens","date":"2017-05-30","tier":1,"note":"Clemens's own venue, his direct reply to critics — referenced by Borjas's own paper as introducing the 'fully-interactive race model' variant. archive_page tool was unavailable this session (permission not granted), so this could not be quote-verified; treated as a further lead, not a core claim source."},{"url":"https://davidroodman.com/blog/2017/05/25/four-points-on-the-debate-over-the-impact-of-mariel-boatlift/","author":"David Roodman","date":"2017-05-25","tier":2,"note":"Named independent methodologist's own venue; could not be archived/quote-verified this session (archive_page permission unavailable). Further lead only."},{"url":"https://www.cato.org/blog/stephen-miller-doesnt-understand-economics-immigration","author":"Cato Institute (unnamed/attributed blog post per search snippet)","date":"unknown, cited via search summary only","tier":3,"note":"Search-summary claimed 'Borjas's response to Clemens and Hunt is weak' — this is a partisan-venue value judgment, not independently confirmed by direct read this session. Not used as a claim source; noted only as a further lead."}]
---


This capture goes to the primary sources behind [[claim-mariel-wage-effect-may-be-1980-census-methodology-artifact]], which had recorded the Clemens–Hunt census-artifact argument and Borjas's timing rebuttal only from a Tier-2 secondary retelling (Silvia Merler, Bruegel, 2017). Both primary papers were located and read directly: Michael Clemens and Jennifer Hunt, "The Labor Market Effects of Refugee Waves: Reconciling Conflicting Results" (NBER Working Paper 23433, May/July 2017; published *ILR Review* 72(4), 2019), and George Borjas, "Still More on Mariel: The Role of Race" (NBER Working Paper 23504, June 2017) — Borjas's direct, dedicated reply to Clemens and Hunt. The final SAGE-published version of Borjas's reply (*ILRR* 72(4), 2019, same title lineage) returned HTTP 403 on every route tried this session, so the NBER working-paper text is the primary used here for Borjas's side; it is presented by Borjas himself as making the identical argument.

---

## Claim: Clemens and Hunt argue the Mariel wage effect Borjas measured is largely explained by a compositional artifact in the Current Population Survey — not a real labor-market response — driven partly by a nationwide, Mariel-unrelated increase in CPS coverage of low-skill Black men around the 1980 census

**Claim type:** specific technical-mechanism claim. **Tier 1–2 required — cleared.**

Clemens and Hunt's own paper states the core finding directly: "We show that conflicting findings on the effects of the Mariel Boatlift can be explained by a large difference in the pre- and post-Boatlift racial composition in subsamples of the Current Population Survey extracts. This compositional change is specific to Miami, unrelated to the Boatlift, and arises from selecting small subsamples of workers." They offer three contributing reasons for the compositional shift, only one of which is a Mariel-adjacent real-world event (the arrival of roughly 15,000 low-income Black Haitian migrants in 1980, a separate refugee flow from the Cuban Marielitos). The other two are measurement artifacts: "A second reason is the increased coverage of low-skill U.S. black men around 1980 in surveys run by the Census Bureau, who had lower average incomes than non-blacks. Major efforts to raise coverage of blacks, especially males, in nationally representative surveys were spurred by political pressure in the run-up to the 1980 census" — citing the 1978 Levitan Commission's finding of Black-male undercounting in the 1970 census, Senate hearings describing the Census Bureau as "embattled" and engaged in "massive efforts to improve coverage," and a lawsuit by Miami's mayor alleging undercounts of low-income Black residents. A third, related reason: "Increases in coverage of low-skill blacks in the surveys tended to include, at the margin, lower-income blacks relative to previously covered blacks." The paper reports the fraction of Black workers in Borjas's Miami subsample "roughly tripled between the survey conducted in 1979 and the survey in 1985, rising 55 percentage points," with no comparable increase in Card's control cities, Borjas's control cities, or Card's own (broader, high-school-or-less) Miami sample. Clemens and Hunt's own reanalysis, adjusting for the Black share, reports results "similar to those of Card (1990) and Peri and Yasenov (2017): little to no wage impact of the Mariel Boatlift is discernable."

**Provenance:**
- source_url: https://www.nber.org/system/files/working_papers/w23433/w23433.pdf
- source_sha: 5d59417e7756084cd78ed6a62023ac48150c5f268fbe051dd5ce7612e3e45639
- source_author: Michael A. Clemens, Jennifer Hunt
- source_date: 2017-05, revised 2017-07 (NBER WP 23433)
- source_tier: 1 (own working paper, primary; fetched via extract_pdf, tls: verified)
- exact quote: "We show that conflicting findings on the effects of the Mariel Boatlift can be explained by a large difference in the pre- and post-Boatlift racial composition in subsamples of the Current Population Survey extracts. This compositional change is specific to Miami, unrelated to the Boatlift, and arises from selecting small subsamples of workers." / "A second reason is the increased coverage of low-skill U.S. black men around 1980 in surveys run by the Census Bureau... Major efforts to raise coverage of blacks, especially males, in nationally representative surveys were spurred by political pressure in the run-up to the 1980 census."

---

## Claim: Borjas's timing rebuttal shows the sharp jump in the Black share of the March CPS sample occurred in a single survey transition (1979→1980), while the steepest wage declines he measured occurred years later (1981–1986), with no black-share movement in that window — the "artifact" and the "effect" do not move together in time

**Claim type:** specific technical-mechanism claim, with load-bearing quantitative figures. **Tier 1–2 required — cleared.**

Borjas's direct reply states the timing objection explicitly: "it is evident that something strange happened to this fraction in calendar year 1979 in the March CPS (which corresponds to survey year 1980), when it rose from 36.3 percent in 1978 to 63.0 percent in 1979." He then argues the Black share was flat exactly when the wage decline was steepest: "nothing whatsoever happened to the black share of the workforce in the March CPS between the years 1979 and 1983. Notably these are the years that witnessed the largest drop in the average wage of Miami's low-skill workforce... it is impossible to explain the steep wage drop in terms of a statistical spuriousness created by a rising black share in the low-skill workforce. And this leads to an obvious inference: the Clemens-Hunt argument is not consistent with the timing of the increase in the black share and the drop in the average low-skill wage." He reports a parallel pattern in the separate CPS-ORG extract, where "the average low-skill wage in Miami... fell dramatically between 1980 and 1984 while the black share rose slightly and then declined slightly over the period." Borjas also reports the 1980 decennial census itself (taken weeks before the Boatlift) already showed a Black share of 54.5% in the relevant low-skill sample, consistent with his reading that the March CPS's sudden 1979-to-1980 jump reflects "a systematic undercounting or misallocation of low-skill black workers in the March CPS prior to the 1980 survey year" rather than a real, Boatlift-timed shift.

**Provenance:**
- source_url: https://www.nber.org/system/files/working_papers/w23504/w23504.pdf
- source_sha: b61014f32b4f10b4d189260d5a034442b0157d34091c6ecf53758eac36918a04
- source_author: George J. Borjas
- source_date: 2017-06 (NBER WP 23504)
- source_tier: 1 (own working paper, primary; fetched via extract_pdf, tls: verified)
- exact quote: "the black share... rose from 36.3 percent in 1978 to 63.0 percent in 1979... nothing whatsoever happened to the black share of the workforce in the March CPS between the years 1979 and 1983. Notably these are the years that witnessed the largest drop in the average wage... the Clemens-Hunt argument is not consistent with the timing of the increase in the black share and the drop in the average low-skill wage."

---

## Claim: The dispute does not resolve cleanly in Borjas's favor on his own account — his simple race-adjustment leaves the wage-drop intact, but a more flexible ("fully interactive") race-adjustment model, which Borjas attributes to a Clemens blog-post reply, sharply shrinks or eliminates the estimated effect in the March CPS data

**Claim type:** specific technical-mechanism claim. **Tier 1–2 required — cleared, on Borjas's own primary text.**

Borjas's rebuttal paper reports that adding a simple, non-interacted race control to his original regressions barely changes his headline result: comparing his original 1984–1986 estimate (-0.393) against the same estimate after simple race-adjustment (-0.385), he writes "the results barely change." But Borjas's own paper then describes a second round: "In a recent blog post, Clemens (2017) noted that the regression evidence summarized in Table 1 is indeed correct... The blog post, however, also notes that an alternative approach to adjusting for race — where the race variable in each cross-section is introduced not only as a fixed effect, but as a fixed effect interacted with metropolitan area and education... — takes away much of the significant wage drop. In an important sense, this response moves the 'goalpost' of the Clemens-Hunt criticism of my Mariel paper. It is no longer that the change in the black share of the workforce induced a spurious correlation that led to lower wages in post-Mariel Miami; the evidence reported in the previous sections shows that this particular argument is just plain wrong. It is now instead that the measured wage impact of Mariel could be zero if we calculate the race-adjusted wage by allowing for the racial wage gap for low-skill workers to vary over time in a city like Miami." Borjas's own Table 3 shows this fully-interactive specification reduces his March CPS estimates to near-zero and statistically insignificant (e.g., 1984–1986, all-cities comparison: -0.003, versus -0.251 in the simple race-adjusted version), while the ORG data retain smaller but still negative, significant effects. Borjas argues at length that the fully-interactive model is conceptually flawed (it "nets out" wage effects immigration itself may have driven through the racial wage gap), but he does not dispute that it produces this result — meaning the exchange, on Borjas's own account, shifted from "is the whole effect spurious" (where his timing argument is direct and, on the evidence read here, forceful) to "does the effect survive a specific alternative statistical adjustment for race" (where the answer depends on a modeling choice neither side treats as settled in this text).

**Provenance:**
- source_url: https://www.nber.org/system/files/working_papers/w23504/w23504.pdf
- source_sha: b61014f32b4f10b4d189260d5a034442b0157d34091c6ecf53758eac36918a04
- source_author: George J. Borjas
- source_date: 2017-06 (NBER WP 23504)
- source_tier: 1
- exact quote: "an alternative approach to adjusting for race... takes away much of the significant wage drop. In an important sense, this response moves the 'goalpost' of the Clemens-Hunt criticism of my Mariel paper... It is now instead that the measured wage impact of Mariel could be zero if we calculate the race-adjusted wage by allowing for the racial wage gap for low-skill workers to vary over time in a city like Miami."

---

## Central question status

`[unverified — could not confirm or deny after search, but substantially narrowed]`. Read against each other directly, Borjas's timing rebuttal is a real and specific rejoinder to the simplest version of the Clemens–Hunt story: the sharpest jump in measured Black share in the March CPS is concentrated in one survey-year transition (1978→1979 calendar years), while Borjas's largest measured wage declines occur in later years (1981–1986) when the Black share, on his own figures, was flat. As a rebuttal to "the compositional artifact alone explains the entire wage drop," this holds up on the primary evidence read here. But the exchange did not end there: Borjas's own paper reports that Clemens's own blog-level reply proposed a different, more flexible race-adjustment (interacting race with city, education, and time) that — on Borjas's own reported numbers — sharply reduces the estimated effect in the March CPS, though not in the ORG extract. Whether that later-round adjustment is the *correct* way to control for race is a modeling dispute this capture did not find resolved by either side's own text, and no independent adjudication (a later paper, a survey article, or a published referee report) was located and read this session. The final SAGE-published versions of both papers (2019) could not be fetched (403 errors); it is possible the published record contains a further round not visible in these 2017 working papers.

---

## Further leads

- Michael Clemens, "What Economists Can Learn from the Mariel Boatlift, Part Two: Answering Questions about Our Research" (cgdev.org, 2017-05-30) — Clemens's own direct reply, cited by Borjas as the source of the "fully-interactive race model" counter; not quote-verified this session (archive_page tool unavailable), worth a direct read next.
- David Roodman, "Four points on the debate over the impact of the Mariel boatlift" (davidroodman.com, 2017-05-25) — named independent methodologist's assessment of the whole dispute; not quote-verified this session, would be a useful Tier-2 synthesis to check.
- Both papers' final SAGE/ILRR-published 2019 versions (Clemens & Hunt, *ILR Review* 72(4):818–857; Borjas, *ILRR* 72(4):858–870) returned HTTP 403 on every route tried this session (gborjas.scholars.harvard.edu, journals.sagepub.com abstract-only) — worth another attempt via a different mirror to confirm the working-paper text matches the final published argument.
- Peri and Yasenov's synthetic-control critique of Borjas's sample construction is a separate line of attack, already captured at [[claim-mariel-boatlift-wage-effect-flips-with-sample-construction]] — not re-litigated here.
- Borjas, Grogger & Hanson (2010, *Economica*) on differential immigration effects on Black vs. white low-skill workers, cited in Borjas's rebuttal footnote 2 — relevant background for why a race-interacted model might or might not be appropriate.
- A Cato Institute blog post (via search snippet only, not directly read) asserted "Borjas's response to Clemens and Hunt is weak" — a partisan-venue value judgment, not independently confirmed; flagged only as a pointer, not recorded as a claim.

---

## Entity candidates

- David Card — person — author of the original 1990 Mariel study (no measurable wage effect) that both Borjas's 2017 reappraisal and the Clemens–Hunt reconciliation explicitly measure themselves against; the deepest foundational figure in this whole dispute chain, already covered at [[claim-card-2021-nobel-natural-experiments-labour-economics]] and [[claim-mariel-boatlift-wage-effect-flips-with-sample-construction]].
- George Borjas — person — author of the original 2015/2017 reappraisal finding a large dropout wage decline, and author of the direct timing rebuttal this capture centers on; the figure both Clemens & Hunt and this whole capture are arguing against/with.
- Michael Clemens — person — co-author of the census-artifact/compositional argument; also authored the follow-up blog post that Borjas says shifted the argument's "goalpost."
- Jennifer Hunt — person — co-author of the census-artifact argument (NBER WP 23433).
- Giovanni Peri / Vasil Yasenov — persons — separate synthetic-control critique of Borjas's sample construction, already covered elsewhere in the vault; relevant backdrop but not the subject of this capture.
- David Roodman — person — independent named methodologist who wrote a widely-cited assessment of the whole debate; not yet read directly this session.
- Current Population Survey (CPS) — concept — the survey instrument (March Supplement vs. May/MORG extracts) whose differing sample sizes and coverage changes are the central mechanism under dispute.
- Levitan Commission — concept/historical entity — 1978 US Census Bureau commission whose finding of Black-male undercounting is Clemens & Hunt's cited trigger for the pre-1980-census coverage push.
- Mariel Boatlift — concept — the 1980 Cuban refugee wave to Miami; the canonical natural experiment this entire literature is about.