Estimating duration intervals

Duration intervals measure the dynamic impact of advertising on sales. More precise, the p per cent duration interval measures the time lag between the advertising impulse and the moment that p per cent of its effect has decayed. In this paper, we derive an expression for the duration interval for a general dynamic model linking sales to advertising. Additionally, and this is themain novelty of the paper, we put forward a method to provide confidence bounds around the estimated duration interval. An illustration to real-life data emphasizes its usefulness.marketing;simulation;advertising effects;duration interval

Modeling Consideration Sets and Brand Choice Using Artificial Neural Networks

The concept of consideration sets makes brand choice a two-step process. House-holds first construct a consideration set which not necessarily includes all available brands and conditional on this set they make a final choice. In this paper we put forward a parametric econometric model for this two-step process, where we take into account that consideration sets usually are not observed. It turns out that our model is an artificial neural network, where the consideration set corresponds with the hidden layer. We discuss representation, parameter estimation and inference.We illustrate our model for the choice between six detergent brands and show that the model improves upon a one-step multinomial logit model, in terms of fit and out-of-sample forecasting.brand choice;consideration set;artificial neural network

Do innovation vouchers help SMEs to cross the bridge towards science?

The Dutch innovation voucher aims to stimulate the interaction between small and medium-sized enterprises (SMEs) and public research institutes. This document provides an estimate of the effectiveness of the innovation voucher instrument, employing the fact that the vouchers were assigned randomly by means of a lottery. The main conclusion is that the innovation voucher instrument does stimulate SMEs to engage in many new assignments with public research institutes. Out of every ten vouchers, eight are used for a project that would not have been assigned without such a voucher, one is used for a project that would have been assigned anyhow, and one voucher is not used. An overall assessment of the innovation voucher also needs to take into account the value added of the additional assignments, however. No insights have yet been obtained here.