Ain’t it "Suite"? Bundling in the PC Office Software Market

Our paper examines the importance of office suites for the evolution of the PC office software market in the 1990s. We develop a discrete choice model of product differentiation that enables us to estimate correlation in consumer preferences across spreadsheets and word processors. Estimation confirms strong positive correlation of consumer values for spreadsheets and word processor products, a bonus value for suites, and an advantage for Microsoft products. We use the estimated demand model to simulate various ‘hypothetical’ market structures in order to shed light on the welfare and competitive effects of bundling in the office productivity software market. We examine the competitive effects of bundling in a simulated market setting of partial competition, in which Lotus sells only a spreadsheet and WordPerfect sells only a word processor, while Microsoft sells both components as well as a suite. Assuming the rivals remain active in the market, when the correlation is positive, the introduction of the suite is pro-competitive (i.e., beneficial for consumers) on balance. This is mainly because the suite bonus 'value' is much larger than the difference between the suite price and the sum of Microsoft’s component prices when Microsoft does not offer a suite. When there is strong positive correlation (as we find), there are many such consumers who purchase both components separately when suites are not available. All of these consumers 'switch' to the suite when it is introduced, and reap significant benefits. The simulations show that the introduction of Microsoft’s Office suite also expands the distribution of spreadsheets and word processors, and this is beneficial to consumers as well.