Link Internship (Semester B, 2014-2015)

Research Topic: Improving Public Recycling with Nudges: Evidence from a Field Experiment in the Link REIT’s Shopping Centres

This internship was co-organized with the Link REIT. As an integration and extension of the previous internships, it sought to implement the interventions in real community settings, exploring whether the use of nudges (informative cues) can improve public recycling in local shopping malls. Night student interns were recruited, including a POL undergraduate student, Jane MA, and eight postgraduate students from the Master of Arts in Public Policy and Management (MAPPM) programme, namely Yinran HE, Weilu MENG, ChangFang NIE, Panyingxue QIU, Mengyuan WEI, Zepeng YANG, Jingnan YAO and Yinan ZHONG. 

A field experiment was conducted from March to May 2015 in three randomly selected shopping centres of the Link REIT, namely Heng On Commercial Centre, Yu Chui Shopping Centre and Tsz Wan Shan Shopping Centre (control). The interventions were information cues: positive ones giving directions and distance to recycling facilities and negative ones to stop recyclable materials being put in garbage bins. In the control there were no interventions. The experiment adopted A-B-A design and lasted for 8 weeks. The weekly amounts of recyclable materials in each shopping centre were measured and compared.

Consistent with pilot’s findings, the results showed that there has been a net increase of 20% in the weekly average amount of recyclable materials collected after the interventions were installed. Such an increase dissipated in the reversal period where the interventions were removed. This positive result informs a non-financial “nudge” model for improving pro-environmental behaviours in public settings, and implies the potential benefits of applying such kinds of informational practices in different communities. The results of these projects are currently been written up.


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SRO Internship (Semester B, 2014-2015)

Research Topic: Does Source Credibility Matter for Point-of-Decision Prompts? Evidence from a Field Experiment to Increase Stair Use in University Residence Halls

This internship was co-organized with the SRO of CityU. The major goal is to encourage the consistently opting for stair use instead of elevator/escalator use - a form of physical activity that can have important health benefits - on campus through the deliberate use of information cues. Four undergraduate interns, namely Melody CALKINS, Keith CHOI, Danni MAN and Henry NG were recruited. In addition, four PhD students, namely Jingyuan XU, Junhua ZHANG, Xukun ZHANG, and Lingling ZHAO, have been actively engaged in the project. They have worked together with the interns in preparation of the experiment, for example conducting literature review, refining interventions’ design, and making presentation to a guest reviewer Prof. Oliver JAMES.

A field experiment was conducted for 4 weeks from April to May 2015 (1 week pretest and 3 weeks posttest). 4 out of 10 undergraduate residence halls of CityU were randomly selected for the experiment. The interventions were point-of-decision (POD) prompts - i.e. messages placed on or near staircases, elevators, and escalators to encourage individuals to take the stairs. The moderating variable was the source credibility of messages. Three kinds of health messages for POD prompts, namely a health message attributed to a high credibility source, a health message attributed to a low credibility source, and a health message without attributing to a source, were placed respectively in every floor of three residence halls. One residence hall was set as a control. The stair and elevator uses of the residents – i.e. the dependent variable - were recorded by view-from-top video cameras and counted by an automated people-counting software.


The data obtained in the experiment is currently being analysed. A replication and extension of the experiment is planned to be conducted in Semester A 2015-2016.

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