Distinguishing forced versus discretionary replacements in new product diffusion models

Kaya, Maria & Steffens, Paul R. (2010) Distinguishing forced versus discretionary replacements in new product diffusion models. In Proceedings of Annual Meeting of the Academy of Management : Dare to Care : Passion and Compassion in Management Practice & Research, Academy of Management, Montreal, Canada.

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In many product categories of durable goods such as TV, PC, and DVD player, the largest component of sales is generated by consumers replacing existing units. Aggregate sales models proposed by diffusion of innovation researchers for the replacement component of sales have incorporated several different replacement distributions such as Rayleigh, Weibull, Truncated Normal and Gamma. Although these alternative replacement distributions have been tested using both time series sales data and individual-level actuarial “life-tables” of replacement ages, there is no census on which distributions are more appropriate to model replacement behaviour. In the current study we are motivated to develop a new “modified gamma” distribution by two reasons. First we recognise that replacements have two fundamentally different drivers – those forced by failure and early, discretionary replacements. The replacement distribution for each of these drivers is expected to be quite different. Second, we observed a poor fit of other distributions to out empirical data. We conducted a survey of 8,077 households to empirically examine models of replacement sales for six electronic consumer durables – TVs, VCRs, DVD players, digital cameras, personal and notebook computers. This data allows us to construct individual-level “life-tables” for replacement ages. We demonstrate the new modified gamma model fits the empirical data better than existing models for all six products using both a primary and a hold-out sample.

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ID Code: 40395
Item Type: Conference Paper
Refereed: Yes
Keywords: Diffusion of Innovations, Repeat Purchases , Forecasting
Subjects: Australian and New Zealand Standard Research Classification > COMMERCE MANAGEMENT TOURISM AND SERVICES (150000) > BUSINESS AND MANAGEMENT (150300) > Entrepreneurship (150304)
Divisions: Current > Research Centres > Australian Centre for Entrepreneurship
Current > QUT Faculties and Divisions > QUT Business School
Current > Schools > School of Management
Deposited On: 02 Mar 2011 23:25
Last Modified: 02 Mar 2011 23:25

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