{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T15:30:16Z","timestamp":1786721416926,"version":"build-2736575974"},"posted":{"date-parts":[[2026]]},"group-title":"SSRN","reference-count":15,"publisher":"Elsevier BV","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>This paper examines the conditional response of the Nasdaq Composite Index to two categories of narrative-driven shocks during 2020-2026: geopolitical events associated with the Strait of Hormuz and Iran, and corporate and narrative events related to artificialintelligence capital expenditure. The headline result is a documented decoupling: after controlling for the broad market, oil prices, the term structure, and implied volatility, neither category generates statistically detectable mean cumulative abnormal returns at any of seven event-study windows. The Brent crude coefficient absorbs the energy-channel impact of Hormuz disruptions, and the residual response of the Nasdaq is small and insignificant. Subsample analysis suggests the conditional response to Hormuz events shifted in direction across the 2022\/2023 cutoff that marks the onset of the AI capex era, with the (-5, 5) window mean moving from-0.51 percent (n = 6) before the cutoff to +0.75 percent (n = 9) after (Welch t =-1.86, p = 0.10). A secondary, weaker pattern of asymmetric persistence appears at the twenty-day horizon for AI events: positive shocks produce absolute cumulative abnormal returns roughly 2.3 times larger than negative shocks (parametric Welch t =-2.72, p = 0.019). However, a placebo test that draws random non-event dates produces equally extreme ratios in approximately 18 percent of 1,000 Nasdaq Event Study, 2020-2026 2 iterations, indicating the parametric inference is overstated by the small negative subsample (n = 2). The asymmetric persistence pattern is therefore reported as directionally suggestive rather than statistically established. A pre-registered out-of-sample test anchored on the 28 April 2026 OpenAI shortfall reported by the Wall Street Journal three trading days after the data cutoff is described in Section 4.5; the (0, 20) window for that event closes approximately 27 May 2026, and an updated version of this paper will report the realised cumulative abnormal return as a direct test of both the decoupling and the persistence hypotheses.<\/jats:p>","DOI":"10.2139\/ssrn.6667180","type":"posted-content","created":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T13:52:07Z","timestamp":1777384327000},"source":"Crossref","is-referenced-by-count":0,"title":["An Event Study of the Nasdaq Composite During the AI Capex Era"],"prefix":"10.2139","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-8477-9393","authenticated-orcid":true,"given":"Boon 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