Event study methodologies in information systems research

Event studies are based on the theoretical framework of efficient capital markets and the notion that security prices include all information available to the market. As a result, announcements made by firms provide to market participants information that can be impounded into the market price. This paper investigates the use of event studies in information systems and accounting information systems research using a three-pronged approach. First, this paper provides a comprehensive survey of research that uses event study methodologies, where the events are announcements made by firms about issues related to information systems, e.g., announcements of the adoption of enterprise resource planning systems and of the effect of security breaches in firms' information systems. Second, this paper summarizes event study methodologies used in prior research, along with some of the key parameters and concerns associated with their implementation. Third, this paper provides remarks on key event study modeling issues, and it offers recommendations to researchers. ► We examine the use of event studies in the analysis of research questions related to information systems, especially accounting information systems. ► We examine differences in event studies in information systems as compared to other disciplines. ► We provide a comprehensive survey of information systems studies that use event study methodologies. ► We discuss the importance of issues such as confounding events, time, firm size, and future performance.