Dataset: apple_carrover.dat

Source: W. Hoofnagle (1965). "Experimental Designs in Measuring the 
Effectiveness of Promotion," Journal of Marketing Research, Vol.II, pp.154-162

Description: Apple sales by Treatment (color quality), period,
and store in a 3-period crossover design 

Trt 1=75-100% good red color (highly colored) 
Trt 2=50-75% (partly colored) 
Trt 3=50-100% (combination)

variables/columns
Store    8   /* 9 stores  */
period   16   /* 1=Oct-Nov11, 2=Nov13-Nov25, 3=Nov27-Dec09  */
sequuence   24
treatment   32
trt1  39-40   /* 1 if trt=1, -1 if trt=3  */
trt2  47-48   /* 1 if trt=2, -1 if trt=3  */
Carryover  56  /* 0 if period=1, trt in period-1 ow  */
Carry1     63-64   /* 1 if carryover=1, -1 if carryover=3  */
Carry2     71-72   /* 1 if carryover=2, -1 if carryover=3  */
sales      77-80