Experimental Design Details
In this experiment, the interventions are structured around four different vignettes and a control group. Each vignette presents a unique scenario designed to influence the participants' voting behavior regarding the installation of BIO waste containers, compared to the control group that does not receive additional context.
Vignette 1: Imminent Closure of the Getliņi Landfill
Participants are informed that Latvia's largest landfill, Getliņi, will no longer be able to accept unsorted household waste within the next seven to ten years unless there is a significant increase in waste sorting. The closure of Getliņi would necessitate either finding another landfill location in Latvia or more likely, constructing one or more waste incineration plants.
Vignette 2: Cost Savings from Sorting
This vignette highlights that sorting waste can reduce household waste disposal costs by up to 30% because sorted waste containers are collected for a reduced fee or even for free. It is noted that BIO waste is currently collected at a 40% reduced cost, and that 30%-50% of what is thrown into the general waste container could actually be recyclable BIO waste.
Vignette 3: Fines for Non-Compliance
Participants learn that Latvia has been paying approximately 15 million euros annually to the European Union budget as a penalty for insufficient plastic waste recycling. This translates into each adult resident effectively paying around ten euros each year for inadequate sorting. If sorting does not improve, these penalties could increase as the EU mandates that only 10% of waste be landfilled by 2035, a significant reduction from the current 53% at Getliņi.
Vignette 4: Environmental Sustainability
This scenario discusses the role of new technologies in waste management, emphasizing that their effectiveness in reducing environmental impact depends on individual participation in waste sorting. It argues that without active participation, even the most advanced technologies will not achieve their full potential in preserving the environment. Participants are encouraged to engage actively for a sustainable future.
Following the vignette (or no vignette in case of random assignment to the control group), participants are presented with a hypothetical scenario: They are living in a multi-apartment building with another adult, sharing household expenses. Their monthly waste management bill is denoted as [X] euros, which covers the cost of removing unsorted waste containers shared by the building. The building manager has issued an invitation to all apartment owners to vote on whether to install a separate container on the property for sorted organic (BIO) waste. The collection cost for BIO waste containers would be [Y] euros less than that for unsorted waste containers. Consequently, if the vote is favorable, their household could save [Z] euros per year, assuming that an average of 40% of their unsorted waste is actually BIO waste. The participants are then asked how they would vote regarding the installation of this new BIO waste container.
Participants are randomly assigned to one of three different monthly invoice levels for waste management—15, 25, or 35 euros—representing the variable [X]. Additionally, they are assigned to one of two tariffs for collecting BIO containers, which are 40% or 60% less than the cost of collecting unsorted waste, representing the variable [Y]. These combinations result in six distinct potential savings amounts (variable [Z]) that a participant's household could realize over the course of a year.