STEM with Scientific and Technical Writing I

Despite recycling being one of the simplest and most impactful ways for citizens to protect the environment, less than 1/3 of American households recycle. This lack of involvement leads to valuable resources being landfilled and harmful greenhouse gases being produced. To motivate individuals to recycle, an app with the gamification features of a monetary incentive, carbon counter, and statistics page was built using the Flutter framework. The app was tested for one week by three groups of individuals: non-recycling senior citizens, local, and remote. Each participant’s recycling output and motivation to overcome recycling barriers, such as not knowing the impact of ones’ recycling on the environment, before and after the implementation of the app, were compared. After using the app, over 90% of participants reported an increase in motivation to recycle. Additionally, 100% of participants reported that using the app increased their awareness of the impact of their recycling on the environment. These findings show that gamifying recycling in an app is a viable strategy to increase individuals’ motivation to recycle and overcome their barriers to recycling. Additionally, this study has found that non-recycling senior citizens can be motivated to recycle when using a gamified app. This conclusion is crucial because improving recycling habits in a population that does not recycle can make more of an environmental impact than improving the habits of those who already recycle. In future iterations of the app, additional gamification strategies such as points, leaderboards, and teams may be implemented. Keywords: household recycling, gamification, motivation, app development

The need for improved recycling habits across the globe is emphasized in the United Nation’s 12th sustainable development goal (Helmefalk & Rosenlund, 2020). In 2018, the US alone produced over 292 million tons of municipal solid waste (MSW), and of these, only 69 million tons of waste was recycled (United States Environmental Protection Agency, 2022). As climate change has progressed, in part due to the increasing waste production, recycling has been recognized as a tool worth investing in since it supports a circular economy (Nixon & Saphores, 2009; United States Environmental Protection Agency, 2019) and has been shown to lower greenhouse gas emissions (Klaiman et al., 2017). Despite recycling being a simple, practical solution to a pressing global issue, only 32% of households recycle (United States Census Bureau, 2021). Household Recycling Positive recycling habits on a household level are crucial to the success of a waste management system. On the simplest level, these habits include actively participating, and effectively cleaning and sorting the recyclables. Unfortunately, the household recycling rate is significantly less in the United States than in other countries (Klaiman et al., 2017). Previous studies have concluded that those with lower income and less education were less likely to recycle (Klaiman et al., 2017), although other studies have produced opposite results (Nixon & Saphores, 2009). Household recycling habits are crucial to the recycling process, because if households produce better quality recycling, then material recovery facilities (MRFs) can be more efficient and process more recyclables. A 2022 study by Dr. Carlos Correa and colleagues found that only 50% of the recyclables collected by Sao Paulo’s waste collection system were processed by the MRFs (Correa et al., 2022). Additionally, because the quality of recyclables was low, meaning that the products were missorted and/or contaminated, over 35% of the recycling batch was rejected even though only 7.4% of the batch was rejectable material (Correa et al., 2022). Thus, improving household recycling habits, by increasing citizen participation and the quality of the recyclables produced, is greatly needed. Barriers to Effective Household Recycling Currently, there are many barriers which dissuade households from recycling. In a 2009 study, Nixon and Saphores determined that space, time, and safety were the population’s main obstacles to recycling. Additional barriers include not knowing the consequences of poor sorting on the recovery process (Helmefalk & Rosenlund, 2020) and not knowing the significance of one’s actions on the environment (Klaiman et al., 2017). Lastly, needing to hand clean recyclables before sorting them is seen as a major barrier to effective recycling since it necessitates time and effort (Klaiman et al., 2017). If these barriers cannot be overcome, then a household will either choose not to recycle or will produce low quality recycling. This project aims to address the barriers of cleaning recyclables, lacking knowledge of significance, and sorting properly. These barriers were chosen, because if they are relieved, the user will be able to produce high quality recycling, even if another barrier causes them to do so at a lower volume. Existing Solutions There are many existing solutions to encourage citizen recycling. On the App Store, there are apps such as SortIt, by Victor Salamanca, and Catch the Trash, by John Palevich, that teach users to recycle through a sorting game. Although these apps teach users how to sort effectively, they do not encourage any real-world recycling habits. Similarly, apps such as Recycle Coach by Municipal Media help users to determine if a product is recyclable and where they can recycle it. These apps act as educational resources but rely on users being self-motivated to use them. Apps like ZeLoop, by ZeloopTech, and the smart bin system created by Briones and collogues in their 2018 study, have successfully increased citizen recycling participation by offering a monetary reward for reaching defined goals (Briones et al., 2018). However, both systems require users to use specific collection bins. There is currently no solution that motivates and supports users in actively and accurately recycling within their own homes. Gamification Gamification is the process of implementing a motivational affordance that triggers a psychological outcome that further produces a behavioral outcome. This tool has been shown to successfully intrinsically motivate users in many studies (Hamari et al., 2014). Gamification takes game mechanics such as competition, collaboration, points, badges, and leaderboards, and applies them to nongame contexts. This makes users want to complete tasks that were once viewed as unfavorable. Often, gamification effectively is used in education or work settings (Hamari et al., 2014). Gamification in Recycling Overcoming one’s barriers to recycling necessitates intrinsic motivation, and gamification is a tool that is recognized for its ability to intrinsically motivate its users (Helmefalk & Rosenlund, 2020). When gamification is applied to recycling it can help the users overcome their own barriers to recycling and to produce a higher quality and quantity of recyclables. In their 2020 study, Helmefalk and Rosenlund conducted a series of focus groups which discussed the features they would like to see in a gamified recycling app. The participants highlighted that a digital solution was preferred to a material one and that while the recycling process should feel like a game, it should not literally be turned into a game, such as tossing the recyclables into the bin, or interfere with the physical recycling process The focus groups also stated that they would like to have a solution that gives them immediate feedback and praise for their positive environmental actions. Users would also like to receive frequent reminders to recycle and be able to compete against other neighborhoods and zip codes to see who could produce the most recyclables (Helmefalk & Rosenlund, 2020). Leaderboards, badges/awards, and social interactions were also suggested. Monetary motivators have also been shown to be effective in increasing both user participation and mass of recyclables (Briones et al., 2018). Lastly, a gamified recycling solution should be adaptable to diverse home recycling processes (Helmefalk & Rosenlund, 2020). Impact and Success Criteria determining the success of the app include the app’s ability increase the quality and quantity of the recyclables of the individuals that use it. As previously stated, this increase in recycling will work to decrease the amount of greenhouse gas emissions (Klaiman et al., 2017). The improved quality of the recyclables will also improve the efficiency of MRFs (Correa et al., 2022). Additionally, if recyclables are removed from compost and landfill streams, the compost and ash produced after processing will be of higher quality since they do not include plastics (Nixon & Saphores, 2009). Combined, these attributes work to support the United Nation’s 12th sustainable development goal, and combat climate change. Problem Statement There is a lack of motivation to practice good recycling habits such as cleaning and sorting products, especially among those who do not understand the positive effects of recycling on the environment. Objective Obj. 1a: The objective of this project is to program a motivating gamified app for Apple and Android devices that increases the quality of individual’s recycling in a manner that allows them to maintain their current system of recycling. Here, quality refers to how clean and correctly separated the recyclables are. Obj. 1b: The objective of this project is to program a motivating gamified app for Apple and Android devices that increases the quantity of individual’s recycling in a manner that allows them to maintain their current system of recycling. Here, quantity refers to the number of recyclables of each material type (plastic, glass, paper, cardboard) that an individual produces. Obj. 1c: The objective of this project is to program a gamified app for Apple and Android devices that increases the user’s knowledge of proper recycling habits, motivation to recycle and overcome recycling barriers, and belief in the impact of their recycling on the environment.

Over the past 5 months, I have spent over 175 hours on this project. During this time, I have been responsible for researching the field/need, conducting a survey on gamification, programming the gamified recycling app from scratch, conducting testing of the app with human participants, gathering numerical and survey data from participants, and analyzing the gathered data. My mentor, Dr. Kevin Crowthers, assisted in project management. Equipment and Materials The app was programmed in Dart using Google’s Flutter framework. Visual Studio Code (VS Code) was used as an integrated development environment (IDE). Within the app, three plug-ins were used. Provider (version 5.0.0) was used for state management and the passing of variables between classes. Shared Preferences (version 2.0.7) was used to persist data in the app. URL Launcher (version 6.0.13) was used to launch URLs outside of the app to bring users to helpful recycling resources. Calculations within the app determining how much CO2 the user had prevented from being emitted were based on the emission factors found in “Greenhouse gas emission factors for recycling of source-segregated waste materials” (Turner et al., 2015). The app was deployed to devices using Xcode and Android Studio 2 for iOS and Android devices respectively. All surveys used throughout the testing process were created using Google Forms. Technique 1: Gamification Survey To determine which gamification strategies to include in the app, an anonymous survey was conducted using Google Forms. The survey was sent by email to over 500 individuals (ages 13+) across the United States. The majority of survey participants were contacted due to their connection to the Mass Academy of Math and Science or Marianapolis Preparatory School. The questions gathered information regarding how much participants knew about proper recycling habits and how motivated they were to recycle. Participants were also asked to rank how strongly they agreed that each of ten proposed gamification strategies would increase their motivation to recycle and overcome barriers to recycling. For a list of all questions used in the survey, see Appendix 1. Technique 2: App Development The app, Carbon Crush, was programmed in Dart using the Flutter Framework. The top three gamification strategies, as determined by the gamification survey, were each given a page in the app. The “monetary incentive” became the Quests page, where users are given a set of tasks that they must complete in order to receive a gift card to an eco-friendly company. The “carbon counter” became the Carbon Counter page. Here, users are shown the amount of CO2 emissions that their recycling habits have prevented from entering the atmosphere. The page also displays relatable measurements such as the CO2 equivalent in gallons of gas and number of smartphone charges. Lastly, the “analytics report” gamification strategy took the form of the Stats page. It must be noted that the Stats page used in the app differed from the description used in the gamification survey. Whereas the survey described a weekly report that highlighted how the user’s recycling habits improved or worsened over time, the implemented page was an ever-present counter that displayed totals for the number of each material recycled and percentages representing the user’s accuracy of recycling habits. This decision was made because, with participant’s only testing the app for one week, the report would not be able to show their trends over time. Additional pages added to the app were the Log Items, Resources, and Home pages. The Log Items page contains a series of dropdown menus where users record the number, material, cleanliness, and how well separated their recyclables were. The resources page contains links to external sources that can educate the user on various recycling topics. Lastly, the Home page shows an overview of the user’s Carbon Counter and a visual representation of their progress towards the quest. See Appendix 2 for images of each of the app screens. Technique 3: In Home testing Three testing groups, Local (5), Remote (4), and Non-Recycling Senior Citizen (2), were created to measure the effect of the app on individuals in various circumstances. The Local group was created to test how the normal usage of the app effects recycling habits. The Remote group tested whether the added step of taking a picture of one’s recycling before disposing of it had a further effect on the quantity and quality of recyclables. Lastly, the Non-Recycling Senior Citizen group tested the app’s ability to impact individuals who chose not to recycling in their household. All participants followed the same framework for testing. Participants began by completing a pre-survey. This survey measured the participants’ motivation to recycle and knowledge of the impact of recycling on the environment. See Appendix 3 for a complete list of Pre-Survey questions. The testing took place over the course of two weeks. For the first week, participants recycled according to their exhibiting habits. For the senior citizens, this meant continuing their practice of not recycling. Local participants were instructed to keep their recyclables separate from those of other members of their household. The Remote participants were instructed to take a picture of their recyclables. Remote participants were given the option of taking individual pictures of products or larger group pictures. If any product had contained food, participants were asked to capture the inside of the container in the image so that it could be analyzed for cleanliness. At the end of week 1, Remote participants uploaded all images of their recyclables to a shared Google Photos album. Additionally, the recyclables were collected from each Local and Senior Citizen participant. See Appendix 4 for a copy of the Testing Information packet that was shared with all participants. On the first day of week 2, the app was installed for all participants. The app was not published on the App Store or Google Play Store. Instead, it was simply run in release mode on each device. This allowed the app to run on the participants’ phones for one week without having to pay a large developer fee. Xcode was used to download the app for participants with iOS devices and Android Studio 2 was used to download the app for Android devices. After the app was installed, participants were given a demonstration outlining the app’s key features. All participants were instructed to use the resources page to fill any recycling knowledge gaps that they may have. The senior citizens received an extra conversation about the importance of recycling and the impact of an individual’s impact on the environment. This conversation included describing how material recovery facilities worked and what happened to one’s recyclables after they were collected. Then, materials’ various emission factors were outlined. Amounts of recycling were related to the amount of CO2 emissions produced by common activities such as driving a car. Lastly, it was restated why, economically, and environmentally, recycling is an advantage. This conversation was introduced because face-to-face communication has been shown to be one of the most effective ways to get individuals to change their recycling habits (Nixon & Saphores, 2009). At the end of week two, the recyclables were collected from Local and Senior Citizen participants. Remote participants uploaded their week 2 photos to a secondary shared Google Photos album. Additionally, all participants completed a post-survey. This survey asked users if they believed that the app had increased their motivation to recycle and their knowledge of the impact of their recycling on the environment. These repeated questions allow for not only the change in the participants’ recycling output to be analyzed, but also their change in mindset regarding recycling. The post-survey also asked for feedback on the users’ experience with the app and how the app may be improved in the future. See Appendix 5 for a copy of all post-survey questions. The recycling for each participant for each week was logged. The number of products of each material type were totaled, as well as the number of food-contaminated, unseparated, and nonrecyclable products. For simplicity, products were simply marked as clean or food-contaminated, they were not rated on a scale. This caused dirty and extremely dirty products to be rated as having the same negative affect on the batch of recycling. The same logic was applied to the other categories. Statistical Tests To analyze the significance of the data, a paired T-test for mean difference was used. This test was used because each participant produced one week’s worth of recyclables with and without the app and the goal was to determine if their recycling quantity and quality improved with the use of the app. The app will be successful if the mean quantity and quality scores for week 2 are significantly greater than the mean quantity and quality scores for week 2 for all participant groups. Paired T-Test for Mean Difference H_o: µ_d= 0 H_a: µ_d> 0 Four paired t-tests for mean difference were conducted. These tested the significance of the change quantity and quality scores before and after using the app for Local and Remote groups. Due to the low sample sizes, histograms of the differences of week 2 and week 1 scores for all four categories were created (Appendix 6). Of the four histograms created, the only one that portrayed normal distribution of the data was the one representing the local quality scores. This means that all other results cannot be considered statistically significant. No statistical tests were run on the Non-Recycling Senior Citizens group as the sample size was two.