Challenges with the Data Clause Samples

Challenges with the Data. The data reveal a multi-level structure as shown in figure 3. Take Apple Inc. as an example. Apple (firm level) produces a wide range of software of different functionalities for desktops and servers, e.g., multimedia software, internet browser, instant messaging software (software category level). Examples of multimedia software provided by Apple Inc. are QuickTime and Final Cut Pro (business-line level). I refer to QuickTime or Final Cut Pro as a business line because it is the organizational unit responsible for one or more product lines for 5 This data repository, located at ▇▇▇▇://▇▇▇▇▇▇.▇▇▇.▇▇.▇▇▇, is a by-product of an NSF- funded research project on "Understanding Open Source Software". It is hosted by the Department of Computer Science & Engineering, University of Notre Dame. different OSs. Specifically, QuickTime provides multiple product lines, including QuickTime for Windows OS and QuickTime for Mac OS (product-line level). In contrast, Final Cut Pro is only made available for Mac OS (product-line level). Such data structure poses challenge in deciding the appropriate level of analysis. Since my variable of interest is the hazard (instantaneous probability) of the subsequent software upgrade, I chose the product-line level (e.g., Microsoft Excel for Windows OS) as the level of analysis, as opposed to the business-line level that spans multiple product lines (e.g., Microsoft Excel, including all products for Windows OS, Mac OS, and Linux OS) and the firm level (e.g., Microsoft Corp.). I made this choice for the following reasons. First and foremost, software upgrades commonly occur within product lines (▇▇▇▇▇▇ et al. 2010). Second, direct competitors are most properly identified within product lines. Since I am particularly interested in the response pattern of a product line to new releases from its competitors, product-line level is the appropriate level of analysis. In addition, since I am also interested in how the new releases of complementary OS platform influence the response action of a product line, this reaffirms the choice of product line as the appropriate level of analysis. Finally, there have been notable variations in market conditions, features and functionalities, and release timing across different product lines of the same software (e.g., Microsoft Excel for Windows OS vs. for Mac OS). Choosing product line as the level of analysis enables us to capture these differences. Moreover, since the event studied in this paper is the ...