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Product Proliferation: An Empirical Analysis of Product Line Determinants and Market Outcomes

  • Barry L. Bayus

    (Kenan-Flagler Business School, University of North Carolina, McColl Bldg. CB 3490, Chapel Hill, North Carolina 27599)

  • William P. Putsis, Jr.

    (London Business School, Sussex Place, Regent's Park, London NW1 4SA, United Kingdom)

Registered author(s):

    Considering the number of new product introductions and available product varieties today, the practice of product proliferation is visibly evident in many diverse industries. Given its prevalence in practice, understanding the determinants and implications of firm proliferation strategies clearly has important managerial relevance. Previous theoretical research has identified three primary effects of a proliferation strategy: (1) a broad product line can increase the overall demand faced by the firm, (2) a broad product line can affect supply by increasing costs, and (3) broad product lines can have strategic consequences (e.g., long product lines can deter entry, thereby allowing an incumbent firm to raise prices). However, despite the theoretical interest in this common business practice, there has been very little empirical research on this topic. Moreover, no empirical study has simultaneously considered all three of the possible effects associated with a proliferation strategy. Consequently, in this paper we propose a three-equation simultaneous system that captures both the determinants and market outcomes of a firm's product line decisions. In particular, we specify market share, price, and product line length equations, which are estimated by three stage least squares. Using this structure, we empirically study the personal computer industry over the period 1981–1992. Our empirical results demonstrate that proliferation strategies do not have a uni-dimensional explanation. We find that product proliferation decisions have both demand (market share) and supply (price) implications. Our empirical results also suggest that the firm-level net market share impact of product proliferation in the personal computer industry is negative (i.e., the cost increases associated with a broader product line dominate any potential demand increases). As expected, we find that structural competitive factors play an important role in the determinants and market outcomes of a firm's product line decisions. However, we do not find evidence of firms using proliferation strategies to deter entry in this industry. Finally, we also demonstrate that some of the empirical conclusions from previous research are reversed once product line length is specified as endogenous in the share and price specifications.

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    Article provided by INFORMS in its journal Marketing Science.

    Volume (Year): 18 (1999)
    Issue (Month): 2 ()
    Pages: 137-153

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    Handle: RePEc:inm:ormksc:v:18:y:1999:i:2:p:137-153
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    1. Hart, Oliver D, 1985. "Monopolistic Competition in the Spirit of Chamberlin: Special Results," Economic Journal, Royal Economic Society, vol. 95(380), pages 889-908, December.
    2. Gilbert, Richard J. & Matutes, Carmen, 1989. "Product Line Rivalry with Brand Differentiation," Department of Economics, Working Paper Series qt1nr3k6nk, Department of Economics, Institute for Business and Economic Research, UC Berkeley.
    3. Raymond Deneckere & Carl Davidson, 1985. "Incentives to Form Coalitions with Bertrand Competition," RAND Journal of Economics, The RAND Corporation, vol. 16(4), pages 473-486, Winter.
    4. John R. Hauser & Steven P. Gaskin, 1984. "Application of the “Defender” Consumer Model," Marketing Science, INFORMS, vol. 3(4), pages 327-351.
    5. K. Sridhar Moorthy, 1984. "Market Segmentation, Self-Selection, and Product Line Design," Marketing Science, INFORMS, vol. 3(4), pages 288-307.
    6. Sunder Kekre & Kannan Srinivasan, 1990. "Broader Product Line: A Necessity to Achieve Success?," Management Science, INFORMS, vol. 36(10), pages 1216-1232, October.
    7. Mary W. Sullivan, 1992. "Brand Extensions: When to Use Them," Management Science, INFORMS, vol. 38(6), pages 793-806, June.
    8. Roberts, M.J. & Samuelson, L., 1988. "An Empirical Analysis Of Dynamic, Non-Price Competition In An Oligopolistic Industry," Papers 3-88-14, Pennsylvania State - Department of Economics.
    9. Oliver D. Hart, 1985. "Monopolistic Competition in the Spirit of Chamberlin: A General Model," Review of Economic Studies, Oxford University Press, vol. 52(4), pages 529-546.
    10. Brian T. Ratchford, 1990. "Commentary on “Marketing Applications of the Economics of Product Variety”," Marketing Science, INFORMS, vol. 9(3), pages 207-211.
    11. Demsetz, Harold, 1973. "Industry Structure, Market Rivalry, and Public Policy," Journal of Law and Economics, University of Chicago Press, vol. 16(1), pages 1-9, April.
    12. Carter, Richard A. L. & Nagar, Anirudh L., 1977. "Coefficients of correlation for simultaneous equation systems," Journal of Econometrics, Elsevier, vol. 6(1), pages 39-50, July.
    13. Langlois, Richard N., 1992. "External Economies and Economic Progress: The Case of the Microcomputer Industry," Business History Review, Cambridge University Press, vol. 66(01), pages 1-50, March.
    14. John M. Connor, 1981. "Food Product Proliferation: A Market Structure Analysis," American Journal of Agricultural Economics, Agricultural and Applied Economics Association, vol. 63(4), pages 607-617.
    15. Gasmi, Farid & Laffont, Jean-Jacques & Vuong, Quang, 1992. "Econometric Analysis of Collusive Behavior in a Soft Drink Market," IDEI Working Papers 16, Institut d'Économie Industrielle (IDEI), Toulouse.
    16. Stavins, Joanna, 1995. "Model Entry and Exit in a Differentiated-Product Industry: The Personal Computer Market," The Review of Economics and Statistics, MIT Press, vol. 77(4), pages 571-84, November.
    17. Kadiyali, Vrinda & Vilcassim, Naufel & Chintagunta, Pradeep, 1998. "Product line extensions and competitive market interactions: An empirical analysis," Journal of Econometrics, Elsevier, vol. 89(1-2), pages 339-363, November.
    18. Kelvin Lancaster, 1990. "The Economics of Product Variety: A Survey," Marketing Science, INFORMS, vol. 9(3), pages 189-206.
    19. Richard Schmalensee, 1978. "Entry Deterrence in the Ready-to-Eat Breakfast Cereal Industry," Bell Journal of Economics, The RAND Corporation, vol. 9(2), pages 305-327, Autumn.
    20. Perloff, Jeffrey M & Salop, Steven, 1984. "Equilibrium with product differentiation," Department of Agricultural & Resource Economics, UC Berkeley, Working Paper Series qt4cq0m6s3, Department of Agricultural & Resource Economics, UC Berkeley.
    21. Subramanian Balachander & Kannan Srinivasan, 1998. "Modifying Customer Expectations of Price Decreases for a Durable Product," Management Science, INFORMS, vol. 44(6), pages 776-786, June.
    22. Barry L. Bayus, 1998. "An Analysis of Product Lifetimes in a Technologically Dynamic Industry," Management Science, INFORMS, vol. 44(6), pages 763-775, June.
    23. Davidson, Russell & MacKinnon, James G, 1981. "Several Tests for Model Specification in the Presence of Alternative Hypotheses," Econometrica, Econometric Society, vol. 49(3), pages 781-93, May.
    24. Brander, James A & Eaton, Jonathan, 1984. "Product Line Rivalry," American Economic Review, American Economic Association, vol. 74(3), pages 323-34, June.
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