% ============================================================================
% UQO Working Paper — Hedonic House Pricing with LLM & Vision Features
% ============================================================================
\documentclass[12pt,letterpaper]{article}

% --- Encoding & Language ---
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[english]{babel}

% --- Page Layout ---
\usepackage[letterpaper,top=1in,bottom=1in,left=1in,right=1in]{geometry}

% --- Typography ---
\usepackage{mathptmx}
\usepackage{microtype}
\usepackage{setspace}
\onehalfspacing

% --- Math ---
\usepackage{amsmath,amssymb,amsthm}
\usepackage{bm}

% --- Tables ---
\usepackage{booktabs}
\usepackage{tabularx}
\usepackage{multirow}
\usepackage{threeparttable}

% --- Figures ---
\usepackage{graphicx}
\usepackage{subcaption}
\usepackage{float}
\usepackage{tikz}
\usetikzlibrary{arrows.meta,positioning,fit,backgrounds,calc,shapes.geometric}

% --- Colors & Links ---
\usepackage[dvipsnames]{xcolor}
\usepackage[colorlinks=true,linkcolor=NavyBlue,citecolor=NavyBlue,urlcolor=NavyBlue,breaklinks=true,pdftitle={Hedonic House Pricing with Language-Model and Vision Features: Evidence from Quebec Real-Estate Listings},pdfauthor={Simon-Pierre Boucher}]{hyperref}

% --- Bibliography ---
\usepackage[authoryear,round,semicolon]{natbib}
\bibliographystyle{aer}

% --- Captions ---
\usepackage[font=small,labelfont=bf,labelsep=period,justification=justified,singlelinecheck=false]{caption}

% --- Headers & Footers ---
\usepackage{fancyhdr}
\pagestyle{fancy}
\fancyhf{}
\renewcommand{\headrulewidth}{0pt}
\fancyfoot[C]{\thepage}

% --- Section Formatting ---
\usepackage{titlesec}
\titleformat{\section}{\large\bfseries}{\thesection.}{0.5em}{}
\titleformat{\subsection}{\normalsize\bfseries}{\thesubsection.}{0.5em}{}
\titleformat{\subsubsection}{\normalsize\itshape}{\thesubsubsection.}{0.5em}{}

% --- Appendix Support ---
\usepackage[toc,page]{appendix}

% --- Misc ---
\usepackage{enumitem}
\setlist{nosep,leftmargin=*}

% ============================================================================
% METADATA
% ============================================================================
\newcommand{\WPnumber}{14}
\newcommand{\WPtitle}{Hedonic House Pricing with Language-Model and Vision Features}
\newcommand{\WPsubtitle}{Evidence from Quebec Real-Estate Listings}
\newcommand{\WPdate}{July 2026}
\newcommand{\WPversion}{2.0}
\newcommand{\WPabstract}{%
  Hedonic house-price models are bounded by the characteristics an analyst can
  measure, yet much of a home's value is recorded only in the free-text description
  and photographs of its listing. We treat general-purpose AI models as a
  feature-engineering technology for hedonic analysis: a large language model
  converts each description into structured property specifications, and a
  vision--language model converts the façade photograph into objective visual
  attributes, both under strict JSON schemas that render the outputs reproducible
  econometric variables. Using 19{,}123 Quebec house listings, the two AI layers
  raise the $R^2$ of an already rich log--linear hedonic specification from 0.717 to
  0.755, and the vision layer delivers the largest out-of-sample gain of any feature
  block for every estimator, from OLS to gradient boosting and neural networks (best
  ensemble: out-of-sample $R^2$ of 0.779, median absolute error 14.0\%). The
  extracted attributes carry economically sensible implicit prices---2.3\% per point
  of curb appeal, 3--4\% for brick or stone façades---that survive
  municipality-clustered inference.
}
\newcommand{\WPkeywords}{hedonic pricing, house prices, large language models, computer vision, feature engineering, Quebec}
\newcommand{\WPjel}{R31, C21, C55, R21}

% --- Author ---
\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/data}
\input{sections/methodology}
\input{sections/results}
\input{sections/benchmark}
\input{sections/robustness}
\input{sections/conclusion}

% ============================================================================
% Declarations (Elsevier requirements)
% ============================================================================
\section*{Declarations}

\paragraph{Funding.} This research did not receive any specific grant from funding
agencies in the public, commercial, or not-for-profit sectors.

\paragraph{Declaration of competing interest.} The author declares that he has no
known competing financial interests or personal relationships that could have
appeared to influence the work reported in this paper.

\paragraph{Data availability.} The listing data were collected from publicly
accessible web platforms (Realtor.ca and DuProprio) on 3~July~2026. The full
data-construction code, the extraction schemas, and the derived analysis dataset
(excluding copyrighted listing text and images) are available from the author upon
reasonable request.

\paragraph{Use of AI models.} Large language and vision--language models
(\texttt{gpt-4o-mini} and \texttt{claude-haiku-4-5}) are the object of study of this
paper and were used exclusively as documented in Section~\ref{sec:methodology} to
extract structured features from listing text and photographs. They were not used to
generate the analysis or the conclusions of the paper.

\newpage
\bibliography{references}

\input{appendix/appendix}

\end{document}