ABSTRACT
Ⅰ. Introduction
Ⅱ. Literature Review and Hypothesis Development
2.1. Observational Learning (OL)
2.2. Multihoming
2.3. Mobile App Stores and Platform Policies
2.4. Within Popularity Effects
2.5. Between Popularity Effects
Ⅲ. Data and Economic Estimation
Ⅳ. Interpretation and Conclusion
4.1. Results and Further Analysis
4.2. Robustness Analysis
Ⅴ. Conclusion