It is known in marketing science that an advertiser under- or overspends mi
llions of dollars on advertising because the estimation of advertising effe
ctiveness is biased. This bias is induced by measurement noise in advertisi
ng variables, such as awareness and television rating points, which are pro
vided by commercial market research firms based on small-sample surveys of
consumers. In this paper, we propose a denoised regression approach to deal
with the problem of noisy variables. We show that denoised least squares e
stimators are consistent. Simulation results indicate that the denoised reg
ression approach outperforms the classical regression approach. A marketing
example is presented to illustrate the use of denoised least squares estim
ators.