\begin{table}[H]\centering
\caption{Placebo Tests across Semantic Factors}\label{tab:placebo}
\small
\begin{tabular}{lccc}\toprule
& \multicolumn{2}{c}{Q5$-$Q1 spread (\%/yr)} & Interaction \\\cmidrule(lr){2-3}
Semantic factor & Pre (2010--21) & Post (2022--24) & $z\times$Post (pp/SD) \\\midrule
AI adoption$^{\dagger}$ & +2.2 \tstat{2.04} & +14.3 \tstat{2.15} & +2.0 \tstat{1.17} \\
AI infrastructure$^{\dagger}$ & +1.4 \tstat{0.91} & +13.6 \tstat{2.44} & +2.8 \tstat{2.63} \\
AI disruption risk$^{\dagger}$ & +3.1 \tstat{2.47} & +14.1 \tstat{2.07} & +1.1 \tstat{0.60} \\
ESG commitment & -2.5 \tstat{-2.82} & -8.8 \tstat{-2.27} & -0.6 \tstat{-0.76} \\
Climate risk & -0.8 \tstat{-1.38} & -5.0 \tstat{-2.48} & +0.1 \tstat{0.17} \\
Cybersecurity & +2.6 \tstat{1.96} & +13.5 \tstat{2.12} & +0.9 \tstat{0.64} \\
Automation/labor & +2.1 \tstat{1.91} & +7.2 \tstat{1.29} & +0.0 \tstat{0.01} \\
Macro risk & -1.6 \tstat{-2.02} & -0.5 \tstat{-0.11} & +1.3 \tstat{1.06} \\
\bottomrule
\end{tabular}
\tablelegend{This table re-runs the structural-break design on all eight semantic factors in the database to test whether the post-2022 re-rating is specific to AI. For each factor it reports the equal-weighted Q5$-$Q1 forward-return spread (in percent per year, with Newey--West $t$-statistics) in the pre-period (2010--2021) and post-period (2022--2024), together with the coefficient on the interaction of the factor's within-year $z$-score with the post-2022 indicator, in percentage points per standard deviation (winsorized forward return, size and momentum controls, standard errors clustered by formation year). The post-ChatGPT increase in the spread is largest for the three AI-related factors, marked with a dagger ($\dagger$), and for cybersecurity, which is bundled with technology exposure; automation/labor language also rises, whereas ESG-commitment and climate-risk disclosure earn \emph{negative} post-2022 spreads and macro-risk disclosure shows essentially none. Because the post-period contains three annual spreads, the $t$-statistics in column~3 are indicative only; none of the eight interaction coefficients other than AI infrastructure is significant at conventional levels.}
\end{table}