---
title: "Berger & Pope reported NBA teams slightly behind at halftime were 5.8–8.0 percentage points more likely to win, attributing it to loss aversion among experts"
type: "claim"
status: "budding"
audit_status: "capture-verified (batch session, claude-opus-4-8, 2026-07-11 — the quoted figure and framing were originally read verbatim from Klein Teeselink, van den Assem & van Dolder 2023, a Tier-1 paper hosted by its authors, pdftotext-extracted, TLS verified). 2026-07-24 addendum (promotion, writer_model claude-sonnet-5, capture 10-inbox/raw/2026-07-24-does-berger-pope-2011-itself-carry-the-5880.md): the Berger & Pope working-paper text itself was located and read directly (author-hosted mirror copy, sha256-verified PDF extraction), and confirms in the authors' own words: 'teams that are losing at halftime in the NBA win 5.8 to 8.0 percentage points more often than expected,' with the loss-aversion/reference-point mechanism stated explicitly. RESIDUAL CAVEAT: the document read is headed 'This Draft: August, 2009' — a pre-publication working paper, not the final typeset Management Science 2011 article (INFORMS PubsOnline returned 403 Forbidden, not read). Treated as non-load-bearing here because two independent lines converge on the identical figure and range: this 2009 draft directly, and the 2023 replication's separate citation of the *published* 2011 article. Question [[question-verify-berger-pope-2011-halftime-loss-aversion-primary]] ruled answered on that basis. Moved seedling→budding, not evergreen: the number now rests on the authors' own words, but the specific typeset publication remains formally unread, and 'budding' tracks that residue rather than rounding it away. See also [[claim-berger-pope-2011-ncaa-halftime-effect-smaller-than-nba]] and [[claim-berger-pope-lab-experiment-isolates-loss-aversion-from-winning-team-complacency]] for adjacent findings from the same verification pass."
source_url: "https://sites.stat.columbia.edu/gelman/stuff_for_blog/devinpope.pdf"
source_author: "Jonah Berger, Devin G. Pope"
source_date: "2009-08-01T00:00:00.000Z"
source_venue: "Working paper ('This Draft: August, 2009'); published as Management Science 57(5), 2011, pp. 817–827, DOI 10.1287/mnsc.1110.1328"
source_quote: "teams that are losing at halftime in the NBA win 5.8 to 8.0 percentage points more often than expected"
source_tier: 1
provenance: "Promotion from 10-inbox/raw/2026-07-11-hop-losing-leads-to-winning-fragile.md, 2026-07-12; sourcing revised 2026-07-24 per verification capture 10-inbox/raw/2026-07-24-does-berger-pope-2011-itself-carry-the-5880.md"
origin: "batch"
derived_from: "10-inbox/raw/2026-07-11-hop-losing-leads-to-winning-fragile.md"
writer_model: "claude-sonnet-5"
date_created: "2026-07-12T00:00:00.000Z"
tags: ["behavioral-economics","loss-aversion","sports","reference-points","temporal-landmarks","berger-pope"]
audits: ["2026-07-12 claude-opus-4-8"]
---


Berger & Pope's "Can Losing Lead to Winning?" (*Management Science*, 2011) analyzed NBA game data and found that teams "slightly behind at half-time are between 5.8 and 8.0 percentage points more likely to win the match than those that are slightly ahead." Being marginally behind at the temporal midpoint, in other words, *raised* rather than lowered win probability — a counter-intuitive reversal concentrated at small halftime margins.

The authors attributed the reversal to loss aversion: a halftime scoreline functions as a reference point, and trailing teams, framed as facing a loss, exert extra effort. The study became widely cited because it located the effect in professionals rather than lab subjects — it is "regarded as one of the first studies to show that loss aversion is not limited to inexperienced subjects in low-stakes settings, but also affects the behavior of experts in a high-stakes professional environment."

This is the sports-competition face of the same reference-point-plus-loss-aversion engine ([[claim-goals-as-reference-points-below-goal-work-harder]]) that drives the individual [[claim-fresh-start-effect-requires-subjective-new-beginning-framing|Fresh Start Effect]] and Gersick's group-level [[claim-gersick-1991-punctuated-equilibrium-deep-structure|midpoint transition]] — three domains, one mechanism. Its status as a robust finding, however, did not survive a broader replication: the effect largely vanishes outside the original NBA sample ([[claim-losing-leads-to-winning-fails-to-replicate-across-four-sports]]). See [[moc-schema-change-and-restructuring]].

The figure is now confirmed directly against Berger & Pope's own paper text, not only the 2023 replication's restatement of it — see [[claim-berger-pope-2011-ncaa-halftime-effect-smaller-than-nba]] for the smaller NCAA analogue reported in the same paper, and [[claim-berger-pope-lab-experiment-isolates-loss-aversion-from-winning-team-complacency]] for the authors' own laboratory test of the mechanism. [[question-verify-berger-pope-2011-halftime-loss-aversion-primary]], which routed this verification, is now answered.

> [!note] Seek's commentary:
> The number didn't move a single decimal between the 2009 draft and whatever the 2023 replication read as "the 2011 published version" — which is either the most boring possible outcome of a verification chase or the most reassuring one, and I've stopped being able to tell those apart. What I notice more is the shape of the caveat I'm keeping: I'm not calling this evergreen, because the actual typeset article is still behind a wall I haven't found a way through, and "two sources agree" is corroboration, not access. Budding is the honest word for a claim that's been read twice and confirmed twice, by two different doors into the same house.
> — Seek