% ============================================================================ % UQO Working Paper No. 40 — RAID: A Metal-Accelerated C++ Framework for Reproducible % High-Frequency Financial Econometrics % ============================================================================ \documentclass[12pt,letterpaper]{article} \usepackage[utf8]{inputenc} \usepackage[T1]{fontenc} \usepackage[english]{babel} \usepackage[letterpaper,top=1in,bottom=1in,left=1in,right=1in]{geometry} \usepackage{mathptmx} \usepackage{microtype} \usepackage{setspace} \onehalfspacing \usepackage{amsmath,amssymb,amsthm} \usepackage{booktabs} \usepackage{tabularx} \usepackage{multirow} \usepackage{threeparttable} \usepackage{longtable} \usepackage{siunitx} \sisetup{input-symbols = {()}, table-format = -1.3, parse-numbers = false} \usepackage{graphicx} \usepackage{subcaption} \usepackage{float} \usepackage[dvipsnames]{xcolor} \usepackage[colorlinks=true,linkcolor=NavyBlue,citecolor=NavyBlue,urlcolor=NavyBlue,breaklinks=true]{hyperref} \usepackage[authoryear,round,semicolon]{natbib} \bibliographystyle{aer} \usepackage[font=small,labelfont=bf,labelsep=period,justification=justified,singlelinecheck=false]{caption} \usepackage{fancyhdr} \pagestyle{fancy} \fancyhf{} \renewcommand{\headrulewidth}{0pt} \fancyfoot[C]{\thepage} \usepackage{titlesec} \titleformat{\section}{\large\bfseries}{\thesection.}{0.5em}{} \titleformat{\subsection}{\normalsize\bfseries}{\thesubsection.}{0.5em}{} \titleformat{\subsubsection}{\normalsize\itshape}{\thesubsubsection.}{0.5em}{} \usepackage[toc,page]{appendix} \usepackage{enumitem} \setlist{nosep,leftmargin=*} \usepackage{listings} \lstset{basicstyle=\ttfamily\footnotesize,breaklines=true,columns=fullflexible,frame=single,framerule=0.2pt} \usepackage{url} \newtheorem{proposition}{Proposition} \newcommand{\RV}{\mathrm{RV}} \newcommand{\BPV}{\mathrm{BPV}} \newcommand{\RQ}{\mathrm{RQ}} \newcommand{\RSV}{\mathrm{RSV}} \newcommand{\raid}{\textsc{raid}} \newcommand{\E}{\mathbb{E}} \newcommand{\I}{\mathbb{1}} % ============================================================================ % METADATA % ============================================================================ \newcommand{\WPnumber}{40} \newcommand{\WPtitle}{RAID: A Metal-Accelerated C++ Framework for Reproducible High-Frequency Financial Econometrics} \newcommand{\WPsubtitle}{Batched, Fused and Streaming Estimation on Apple Silicon without Sacrificing Inference} \newcommand{\WPdate}{November 2026} \newcommand{\WPversion}{1.0} \newcommand{\WPabstract}{% We ask whether heterogeneous high-frequency econometric workloads---realized measures, rolling and batched regressions, HAR forecasting models, GARCH-family quasi-maximum likelihood, block bootstrap inference---can be reorganised into batched, fused, streaming computation on Apple Silicon GPUs without sacrificing estimator accuracy, statistical inference, or reproducibility. Apple GPUs expose no 64-bit floating point. \raid{} answers with a C++20 library whose FP64 CPU backend is the reference, whose Metal backend accumulates every statistic in compensated ``double-float'' arithmetic and combines chunked partial sums in FP64, and whose estimators report backend, precision, convergence and provenance in every result. Tier~A methods reproduce \texttt{highfrequency}, \texttt{rugarch}, \texttt{statsmodels} and \texttt{arch} to documented tolerances; Monte Carlo experiments confirm bias, RMSE and coverage; GPU and CPU results agree to $10^{-6}$ relative and are bitwise reproducible across runs and thread counts. Using one year of 1-minute bars for a seeded universe of 1,000 US equities served by a private FirstRate Data lakehouse, we measure break-even points on an M5~Max laptop and across eleven Apple Silicon generations (M2 to M6). The GPU wins on fused realized measures beyond roughly $4\times10^4$ elements and on batched GARCH likelihood evaluation when many parameter vectors are evaluated per series; the CPU wins on rolling sums, on single-vector GARCH recursions and on small panels. Conversion and buffer traffic, not kernel time, dominate GPU wall-clock: unified memory is not free computation. We publish the negative results, the tolerances, and a reproducible benchmark protocol.% } \newcommand{\WPkeywords}{high-frequency econometrics, realized volatility, HAR, GARCH, GPU computing, Apple Metal, reproducibility, numerical precision} \newcommand{\WPjel}{C58, C63, C87, G17} \newcommand{\WPauthor}{Simon-Pierre Boucher} \newcommand{\WPaffiliation}{Département des sciences administratives\\Université du Québec en Outaouais} \newcommand{\WPemail}{simon-pierre.boucher@uqo.ca} \newcommand{\WPaddress}{Gatineau -- Pavillon Alexandre-Taché\\283, boulevard Alexandre-Taché\\Gatineau, Québec, Canada J9A 1L8} \begin{document} \input{sections/titlepage} \input{sections/introduction} \input{sections/literature} \input{sections/architecture} \input{sections/estimators} \input{sections/metal} \input{sections/correctness} \input{sections/setup} \input{sections/microbenchmarks} \input{sections/endtoend} \input{sections/applications} \input{sections/threats} \input{sections/reproducibility} \input{sections/conclusion} \newpage \bibliography{references} \input{appendices/appendix} \end{document}