Hi Everyone,

I am doing time modelling for a new Shampoo brand on a particular Brand Metric say 'Brand buy/use Most Often'( this metric is captured by Market Research data collecting firm through the personal interviews of all shampoo consumers, and have the weekly base of 50) and analysis is done on 3 years of weekly data.

Since, the Brand launched only in 1st year of the analysis, I have seen upward shift in the endorsement for that Brand Metric in 2nd and 3rd year respectively, though the Brand didnot shift its media spend in 2nd & 3rd except its distribution has increased and it is assumed that since the brand is becoming older, so due product experience also the endorsement level is increasing with time . So, I had put a dummy for 2nd year as well as for 3rd year and I am getting positive contribution for both 2nd year and 3rd year respectively. My objective of the analysis is to calculate ROI of Media spend on this particular Brand Metric.

So my question is, did I have done this right by taking separate dummy for 2nd and 3rd year? or is there any other method through which I can controll the impact of the upward trend in brand endorsement.

Thanks

Danish