Predicting future purchases with the Poisson log-normal model

The negative binomial distribution (NBD) has been widely used in marketing for modeling purchase frequency counts, particularly in packaged goods contexts. A key managerially relevant use of this model is Conditional Trend Analysis (CTA)—a method of benchmarking future sales utilizing the NBD conditional expectation. CTA allows brand managers to identify whether the sales change in a second period is accounted for by previous non-, light, or heavy buyers of the brand. Although a useful tool, the conditional prediction of the NBD suffers from a bias: it under predicts what the period-one non-buyer class will do in period two and over predicts the sales contribution of existing buyers. In addition, the NBD's assumption of a gamma-distributed mean purchase rate lacks theoretical support—it is not possible to explain why a gamma distribution should hold. This paper therefore proposes an alternative model using a log-normal distribution in place of the gamma distribution, hence creating a Poisson log-normal (PLN) distribution. The PLN distribution has a stronger theoretical grounding than the NBD as it has a natural interpretation relying on the central limit theorem. Empirical analysis of brands in multiple categories shows that the PLN distribution gives better predictions than the NBD.     

Fragmentation and East Asia's information technology trade

This article studies the growth and determinants of information technology (IT) trade in the Asia-Pacific region. We argue that the rise of IT trade must be understood within the context of increasing vertical fragmentation of production processes that has occurred over the past two decades. To evaluate this empirically, we estimate a set of pooled bilateral IT export equations for eight Asian countries, the USA and the EU, where foreign direct investment (FDI) inflows are introduced as a proxy for fragmentation. We apply a panel cointegration approach that allows for heterogeneity in short-run dynamics and in fixed effects. Consistent with production fragmentation, we find that the evolution of IT trade can be explained in part by traditional income and relative price effects but also by FDI inflows.     

Contents Volume 18 2001

Volume Contents

Contents Volume 18 2001     

The impact of award uncertainty on settlement negotiations

Legal disputes are often negotiated under the backdrop of an adjudicated award. While settlements are common, they are not universal. In this paper, we empirically explore how uncertainty in adjudicated awards impacts settlement negotiations. To do so, we develop an experimental design to test how increases in variance and positive skewness of the award distribution impact negotiations and settlement rates. We find increases in variance decrease settlement rates, while increases in skewness generally increases settlement rates. We also gather individual measures of risk aversion and prudence, and incorporate these measures into the analysis to test for heterogeneous treatment effects. Overall, our results suggest that highly variable adjudicated awards can contribute to the excess use of inefficient litigation, while more positively skewed awards can reduce the use of inefficient litigation.     

Corporate governance and the market impact of the Financial Services Modernization act of 1999 on bank returns and trading volume

Recent deregulation of financial services by the Financial Services Modernization Act of 1999, also known as the Gramm-Leach-Bliley Act (GLB), places more reliance on corporate governance to oversee the actions of financial institutions. We examine whether corporate governance variables explain bank shareholder reaction to GLB passage. We find that banks with better board oversight react favorably to the GLB and banks with less effective board monitoring react less favorably to the GLB. Banks with lower leverage, lower insider ownership, less board activity, a smaller board, fewer inside directors, and less visibility respond more positively to the GLB. Results indicate investor approval of the legislative effort to increase the role of corporate governance in the banking industry and affirm the importance of effective corporate oversight among financial institutions. The authors thank the reviewers for their insights and suggestions.