Frank M. Bass

A New Product Growth Model for Consumer Durables

A growth model for the timing of initial purchase of new products. The basic assumption of the model is that the timing of a consumer’s initial purchase is related to the number of previous buyers. A behavioral rationale for the model is offered in terms of innovative and imitative behavior. The model yields good predictions of the sales peak and the timing of the peak when applied to historical data. A long-range forecast is developed for the sales of color television sets.

A New Product Growth for Model Consumer Durables

(This article originally appeared in Management Science, January 1969, Volume 15, Number 5, pp. 215-227, published by The Institute of Management Sciences.) A growth model for the timing of initial purchase of new products is developed and tested empirically against data for eleven consumer durables. The basic assumption of the model is that the timing of a consumers initial purchase is related to the number of previous buyers. A behavioral rationale for the model is offered in terms of innovative and imitative behavior. The model yields good predictions of the sales peak and the timing of the peak when applied to historical data. A long-range forecast is developed for the sales of color television sets.

New Product Diffusion Models in Marketing: A Review and Directions for Research

The diffusion of an innovation traditionally has been defined as the process by which that innovation is “communicated through certain channels over time among the members of a social system” (Rogers, 1983, p. 5). As such, the diffusion process consists of four key elements: innovation, communication channels, time, and the social system.

Adjusting Stated Intention Measures to Predict Trial Purchase of New Products: A Comparison of Models and Methods

Several of the largest marketing research suppliers estimate that 70 to 90% of their clients use purchase intention scales in some form on a regular basis. Though there have been many studies of pu...

A Simultaneous Equation Regression Study of Advertising and Sales of Cigarettes

Application of simultaneous equation regression methods in analyzing limited time series data for sales and advertising. In testing sales arid advertising relationships for filter and nonfilter cigarette brands, a model in which the advertising elasticity for filter brands is substantially greater than that for nonfilter brands is not rejected.

Market Segmentation: Group Versus Individual Behavior

The argument that socioeconomic variables do not provide an adequate basis for market segmentation of grocery products is disputed. A theoretical framework for segmentation measurement in terms of ...

Impact of a Late Entrant on the Diffusion of a New Product/Service

Starting with Basss (1969) article, diffusion researchers have predominantly focused on modeling category-level sales growth and issues surrounding it. In this article, the authors propose a brand-level diffusion model and demonstrate its managerial use by applying it to the following issue: If a new brand enters a category that has not attained its peak sales, how can a practicing manager evaluate its impact on the category and on the incumbent brands? The proposed model helps the manager diagnose whether the late entrant affects the market potential and/or the diffusion speed of the category and of the incumbent brands. The authors test the model using brand-level sales data from the cellular telephone industry in multiple markets.

A Multibrand Stochastic Model Compounding Heterogeneous Erlang Timing and Multinomial Choice Processes

The model developed in this paper incorporates two submodels a purchase timing model which describes the occurrence over time of purchases of the product class and a multibrand stochastic choice model which specifies how any brand may be chosen on a given purchase occasion. The mathematical derivations obtained by combining both submodels lead to the identification of the formal connection between the aggregates of the market—in particular, market share, penetration, duplication and brand switching. The combining is done under the assumption of independence between the zero-order choice process and the Erlang purchase timing process. The model is fully determined when the following four types of parameters are known the market shares, mn, a measure of heterogeneity of the population in terms of choice, p, the order of the Erlang timing process, r, and two parameters which describe the distribution over the population of the purchase rate of the product class—a shape parameter k and a scale parameter c. An...

Market share response and competitive interaction: The impact of temporary, evolving and structural changes in prices

Managing pricing is a challenging task due to the significant impact on shares and the likelihood of strong consumer and competitor reaction. The major contributions of this paper are to assess comprehensive share response to temporary, evolving and structural changes in prices and to determine the level of market share as a function of levels of prices. For the empirical analysis, we examine two consumer product categories and find that it is valuable to distinguish among temporary, evolving and structural changes in prices, as their impact on market shares tends to differ. Further, we find that subsequent competitive reaction will influence predictions of price response. Accordingly, it is important for managers to use conjectures regarding competitive price reactions in assessing the impact of policy changes. We conclude with the strategic implications of the findings and discuss a number of opportunities for future research.

Simultaneous-Equation Regression Analysis of Sales and Advertising *

A simultaneous-equation regression model is developed and tested against aggregative time series data. The test involves the model as well as hypotheses regarding the structural parameters. Restrictions on the structural parameters imply limits on the parameters of the reduced-form equations. Estimates of the reduced-form coefficients must fall within the implied intervals in order for the model to be in agreement with the data.