Social Science Studies and Experiments with Web Applications Author Dawit Bezu Mengistu Supervisor Aris Alissandrakis Exam date 30 August 2018 Subject Social Media and Web Technologies Level Master Course code 5ME11E-VT18 Abstract This thesis explores a web-based method to do studies in cultural evolution. Cu- mulative cultural evolution (CCE) is defined as social learning that allows for the accumulation of changes over time where successful modifications are maintained un- til additional change is introduced. In the past few decades, many interdisciplinary studies were conducted on cultural evolution. However, until recently most of those studies were limited to lab experiments. This thesis aims to address the limitations of the experimental methods by replicating a lab-based experiment online. A web-based application was developed and used for replicating an experiment on conformity by Solomon Asch[1951]. The developed application engages participants in an optical illusion test within different groups of social influence. The major finding of the study reveals that conformity increases on trials with higher social influence. In addition, it was also found that when the task becomes more difficult, the subject's conformity increases. These findings were also reported in the original experiment. The results of the study showed that lab-based experiments in cultural evolution studies can be replicated over the web with quantitatively similar results. Keywords| Cumulative Cultural Evolution, web-based experiment, optical illusion, real-time communication 1 Dedication To Simon & Yohana 2 Acknowledgements I want to thank the Swedish Institute (SI) for granting me a scholarship. I would like to express my great appreciation to my supervisor Dr. Aris Alissandrakis for his ongoing guidance and support; Romain Herault for helping me structure my work; Stefan Aleksikj and Hampus Juhlin for their friendship and support throughout the program. I would also like to thank my mom Almaz, my wife Enyat and my kids Simon and Yohana, my sister Mahlet, and my friend Nebyou for believing in me. 3 Contents 1 Introduction9 1.1 Motivation.................................... 11 2 Background 13 2.1 Overview of Cumulative Cultural Evolution.................. 13 2.2 Methods of Studying Cumulative Cultural Evolution............. 14 2.2.1 Experimental Method.......................... 15 2.2.2 Conformity Experiment......................... 19 2.2.3 Web-based Experiments......................... 20 3 Methodology 23 3.1 Overview..................................... 23 3.2 Experiment Procedure.............................. 25 4 System Description 26 4.1 System Design.................................. 26 4.2 Front-end Development............................. 27 4.3 Back-end Development.............................. 29 4 4.4 Survey Implementation.............................. 32 5 Result and Discussion 34 5.1 Results....................................... 34 5.1.1 First Experiment............................. 34 5.1.2 Second Experiment............................ 35 5.1.3 Post-experiment Interviews....................... 36 5.2 Discussion..................................... 36 6 Conclusion 38 6.1 Future Work................................... 39 Bibliography 39 A Pusher Implementation 44 B SurveyJS Implementation 48 C Images Used for the Experiment 51 5 List of Figures 2.1 Experimental design of a typical Transmission Chain study.......... 16 2.2 Experimental design of a typical Replacement Method study......... 17 2.3 Experimental design of a typical Constant group method study........ 18 4.1 The three versions of the application....................... 27 4.2 Application screenshot (iPhone mockup).................... 29 4.3 Activity Diagram of Pusher implementation.................. 31 5.1 Conformity of groups in the first experiment.................. 35 5.2 Conformity of groups in second experiment................... 36 B.1 Survey editor developed using survey.js library................. 49 C.1 Color Optical Illusion.............................. 51 C.2 M¨uller-Lyer illusion................................ 52 C.3 Scintillating grid................................. 52 C.4 Cafe wall illusion................................. 53 C.5 Color dogs..................................... 53 C.6 Identical colors.................................. 54 6 C.7 Adelson's Checkers Shadow........................... 54 C.8 Rotating snakes.................................. 55 C.9 Ehrenstein illusion................................ 55 C.10 Shepherd's table................................. 56 C.11 The Ebbinghaus illusion............................. 56 C.12 Hering illusion.................................. 57 7 List of Tables 3.1 Comparison between Asch[1951] experiment and the experiment conducted for this thesis.................................... 24 8 Chapter 1 Introduction In the field of cultural evolution studies, it is argued that cultural variation and cultural change are often lacking in empirical support and that experimental simulations of cultural change can provide one means of investigating such issues (Mesoudi[2007]). Even though experimental methods are evidenced to recreate and explore past events in a controlled and systemic manner, they have methodological limitations when it comes to efficiency, scalability and the extent to successfully recreate real-life cultural change. Web-based experiments, a growing yet not well researched trend in social science, are said to have the potential to address some of these limitations as well as translate to external validity. New technologies have changed a lot of our ways and actions as a society. With these advancements, the way to conduct studies and experiments have also evolved for the better. The internet offers a huge potential (and huge samples) for studying cultural transmission experimentally. Despite these engaging highlights, web-based experiments in social science fields still stay in their early stages. The primary goal of this thesis is to help fill this gap by conducting a replicated experiment online, in cultural evolution studies and compare the results with the original lab experiment. In their seminal article on the study of collective social dynamics in cultural markets, J. Salganik and Watts[2009] argue that as opposed to natural scientists, social scientists have long-faced basic issues in testing and exploring new theories. In the same vein, Horton et al.[2011] underline the difficulty of coming up with procedures for online experiments that ensure their internal validity. They suggest a number of factors have been identified that have probably hindered researchers from conducting experiments online. Some of these include the difficult to monitor the identity of participants, that subjects may read the experimental instructions too carelessly and/or make decisions too quickly and/or get 9 significantly distracted during the course of the experiment, and that subjects may also drop out of the experiment for unknown reasons. Earlier literature defines the term cumulative cultural evolution (CCE) as a process in which, \human cultures accumulate changes over many generations, resulting in culturally transmitted behaviors that no single human individual could invent on their own" (Boyd and Richerson[1996]). Most methods used to study cultural evolution extensively rely upon experimental social psychology, theoretical analysis, mathematical or computer models and to a much lesser extent, computer-based experiments. An overview of CCE, its benefits and some of the study methods used are highlighted in the Background section. It is hoped that this thesis work will contribute to this literature by creating a proto- type application aimed to address some of the limitations of a lab experiment in addition to comparison with the proposed method. The main conclusion drawn from the study is that lab-based experiments in cultural evolution studies can be replicated over the web with quantitatively similar results. The results are important to the community of developer wishing to build up and scale the application as a medium for running social experiments over the Internet. They are also important for social scientists wishing to use social exper- iments to research the Internet as a method. The purpose of this thesis work is to design and implement a real-time web-based application for conducting an online experiment. Using the application a well-known ex- periment by Asch[1951] on conformity was replicated. An earlier study by Sherif[1937] on social factors in perception is also used for reference as the two experiments have similar methods and execution. The thesis serves the purpose of identifying some of the technical components and methodological limitations of such experiments. Taking this into account, the following questions are to be investigated as research questions: Research Questions 1. How can web-based experiments be used to address the limitations of experimental methods of conducting cumulative cultural evolution research? 2. Investigate the degree to which social pressure can affect a person to conform, using the web-based experiment method. 3. How well the factors affecting conformity in lab experiments translate to a web-based method? 10 1.1 Motivation The general concept and approach of experimental social psychology for a better under- standing of cultural variation and cultural change have greatly inspired the study reported in this thesis. More specifically two experiments, by Sherif[1937] on social influences