Does Advertising Effectiveness Vary over Time?
(2) if so, what causes the change? and (3) what are the most important factors affecting the effectiveness of advertising? Generic fluid milk advertising in New York City (NYC) is chosen as a case study for applying the general model. This market is of interest because New York state farmers spend almost $11 million a year for fluid milk advertising and more than 60 percent of this money has been invested in the NYC market. Data for milk sales, demographics advertising expenditure, and other milk campaign information (e.g., changes in copy themes) are also available for this market. Monthly data from January 1986 to June 1995 are used, and a thorough description of the data sources is presented in Lenz, Kaiser, and Chung (NICPRE Research Bulletin 97-06). For the empirical estimation of the NYC fluid milk advertising model, per capita fluid milk consumption is assumed to depend on real milk price, income, fluid milk, advertising, competing product advertising, consumer fat concerns, foo
