Housing Exchange Framework to Reduce Carbon Emissions from Commuting

The sample was drawn from a household housing and travel survey conducted by the authors' research team in Beijing between Oct 9th of 2020 and March 16th of 2021. Both on-street surveys and web surveys are applied. On-street surveys were conducted at main subway stations and large industrial/cultural parks, while web surveys were distributed via major social networks (e.g., WeChat groups). The survey uses the convenience sampling, as participants were selected based on accessibility and availability. This approach was chosen due to the practical challenges of conducting random sampling in a large and diverse urban area like Beijing.

The sample was drawn from a household housing and travel survey (named ``Wohnen-Arbeiten-Mobilitaet survey'') jointly conducted by the chair of urban development and chair of land use and transport at the Technical University of Munich between Nov 24th, 2014 until April 16th, 2015, in Munich. Both web surveys and post surveys are applied. This survey has received ethics approval to process individual data. The web survey was posted on a public portal site (www.wam.tum.de) and promoted through newsletters, press conferences, and social media, while postcards with QR codes were sent to residential communities with the help of partner municipalities. This survey uses convenience sampling, as participants were recruited through easily accessible channels. This approach was chosen due to the practical challenges of conducting random sampling in a large, collaborative project involving multiple stakeholders.

The sample was drawn from a Household Travel Survey (HTS) conducted by Land Transport Authority (LTA) in Singapore in 2012. The survey uses a stratified random sampling method to ensure that the survey captures a diverse range of households. The sample is stratified based on key demographic factors such as: Geographical locations (includes households from across all of Singapore’s planning regions), housing type, income levels, and household size and structure.
The HTS collects information on housing location and various aspects of travel, including how respondents commute to work, school, and town centers. All the household members participated the survey. Among to 5.31 million of the population in 2012, 9635 households (35714 individuals) participated in the HTS survey. Among which, 7418 households (12048 employed individuals) are valid with full information of the selected variables. The representativeness of the sample is relatively good (Table \ref{tab_socio_economics_sg}), which improves the generalizability of the survey results.

本样本取自作者研究团队于2020年10月9日至2021年3月16日在北京开展的家庭住房与出行调查。该调查同时采用街头访谈与网络问卷两种形式：街头访谈在主要地铁站及大型产业/文化园区开展，网络问卷则通过微信群组等主流社交网络分发。本次调查采用方便抽样法，即根据参与者的可接触性与可获得性选取样本，之所以选择该方法，是因为在北京市这样大型且多元的城市区域开展随机抽样存在实际困难。

本样本取自慕尼黑工业大学（Technical University of Munich）城市发展学讲席与土地利用与交通学学讲席联合开展的"Wohnen-Arbeiten-Mobilitaet调查"，该调查于2014年11月24日至2015年4月16日在慕尼黑开展。调查同时采用网络问卷与邮寄问卷两种形式，已获得个人数据处理的伦理审批。网络问卷发布于公共门户网站（www.wam.tum.de），并通过通讯简报、新闻发布会及社交媒体进行推广；此外项目合作市政当局协助向居民社区寄送了带有二维码的明信片。本次调查采用方便抽样法，通过易接触的渠道招募参与者，之所以选择该方法，是因为在涉及多方利益相关者的大型协作项目中开展随机抽样存在实际困难。

本样本取自新加坡陆路交通管理局（Land Transport Authority, LTA）2012年开展的家庭出行调查（Household Travel Survey, HTS）。该调查采用分层随机抽样法，以确保样本覆盖多样化的家庭群体，分层依据包括关键人口统计因素：地理位置（涵盖新加坡所有规划区域的家庭）、住房类型、收入水平以及家庭规模与结构。
家庭出行调查收集了住房位置及各类出行相关信息，包括受访者通勤上班、上学及前往城镇中心的出行方式。本次调查覆盖所有家庭成员：2012年新加坡总人口约531万，共有9635户家庭（合计35714名个体）参与了本次调查，其中7418户家庭（含12048名就业个体）的目标变量信息完整，为有效样本。该样本的代表性较好（详见表
ef{tab_socio_economics_sg}），提升了调查结果的可推广性。