我想减少本文档中“摘要”一词与日期之间的间距：
\documentclass[12pt,twoside]{article}
\usepackage[utf8]{inputenc}
\usepackage[font={footnotesize,bf}]{caption}
\usepackage{xcolor}
\usepackage{tabularx}
\usepackage{tikz}
\usepackage{pgfplots}
\usepackage{enumerate} % for lowercase roman numbers with enumerate
\pgfplotsset{width=7cm,compat=1.10}
\usepgfplotslibrary{fillbetween}
%With this, If I don't need the \\ if I want to skip a line and
\usepackage{fancyhdr}
\usepackage{natbib}
\usepackage{amsfonts,amsmath,amsthm,amssymb}
\usepackage{tikz}
\usepackage[a4paper,
includehead,
left={2.2 cm},
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headheight={1.0 cm},
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\setlength{\footnotesep}{10 pt}
\newtheorem{lemma}{Lemma}
\newtheorem{proposition}{Proposition}
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\usepackage{hyperref}
\title{The Environmental Implications of Renting The Runway}
\author{ Matteo Bulgarelli %
\\
\vspace{7pt}
\normalsize KU Leuven\thanks{CEDON, Katholieke Universiteit Leuven, 26 Warmoesberg, 1000 Bruxelles, Belgium, email: [email protected]} \ \ UC Louvain\thanks{CORE/LIDAM, Université Catholique de Louvain, 34 Voie du Roman Pays, B-1348 Louvain la Neuve,
Belgium, email: [email protected]}}
\date{\today}
\hypersetup{
colorlinks=true,
urlcolor=black,
citecolor=blue,
}
\begin{document}
\pagestyle{fancy}
\fancyhf{} % clear existing header/footer entries
\fancyhead[RE,LO]{\rule[-1.6ex]{0pt}{1.6ex}\scriptsize\textbf{Bulgarelli}: \textit{The Environmental Implications of Renting The Runway}}
\fancyhead[RO,LE]{\footnotesize\thepage}
\maketitle
\begin{abstract}
\noindent{\footnotesize
The fashion industry accounts for approximately 10\% of the global $\mathrm{CO_2}$ output, and policymakers and environmental
advocates convened that curbing production is crucial to comply with the targets of the Paris Agreement. Several
supporters of the Circular Economy paradigm have thus identified rental-based business models as a solution to the
problem: upon the payment of a monthly fee, consumers have access to a given number of pieces per month, which
are delivered in two shipments: between the first and the second delivery, the users have to return the first chunk of
items. I study the sustainability of these arrangements by adopting a stylized set-up that features two competitive
fringes of retailers and an Access Based Service Provider (ABSP) that offers a two-period leasing contract; each fringe
produces a horizontally differentiated good, and the subscription to the ABSP gives access to both goods. Consumers display a taste
for variety: their gross surplus from the purchase of both products is super-additive. The green
credential of the ABSP stems from its efficiency in serving the fraction of user that buys both products; with
only one piece per subscriber, the ABSP can provide two distinct outfits, swapping items among its clients between
periods. I show that the entrance of the ABSP reduces total production if and only if users exhibit a sufficiently strong
preference for variety and if the unit production costs are low enough. Subsequently, I analyze the competitive interaction
between the ABSP and the retail side in a Stackelberg game: a retailer that sells both products holds a first-mover
advantage against an ABSP: in this set-up, if the demand side is characterized by very low acceptance of rental
vis-à-vis ownership, then entrance necessarily implies a larger production volume.}
\end{abstract}
\end{document}
编辑：该问题与有关twoside，documentclass但我不明白为什么。