Carefully read the case StainZapper A. Download the data on the case from Blackboard.

a)Then compute the effect of advertising (Hint: Merge data into two periods, one before and one after start of advertising. build a new average city from those with advertising. Then do Diff in Diff).

b)Was advertising profitable?

B C D E F G H K M Table 2 Table 2 Test Market Sales of StainZapper Test Market Sales of StainZapper Time Period Month City Nov. 2018 Dec. 2018 Jan, 2018 Month Week Week Tota 1 Denver Cincinnati St. Louis Total 2 3 2 3 40 4 Denver 30 100 Nov. 2018 70 170 250 240 330 25 230 140 200 30 50 20 751 1860 IN Cincinnati 25 70 120 140 120 180 200 300 200 160 140 AD 1695 40 70 50 160 St. Louis 20 50 100 110 100 130 100 160 90 70 40 30 1000 3 70 100 290 Total 75 160 290 350 390 560 540 790 520 370 380 130 4585 4 100 140 110 350 Dec. 2018 1 170 120 100 390 2 250 180 130 560 240 200 100 540 4 330 300 160 790 Jan. 2019 230 200 90 5201 140 160 70 370 200 140 40 380 60 40 30 130 1860 1695 1000 4555