Case Study 6.3: A Device to Reduce Engine Emissions
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Variables: 

     HC        Hydrocarbon (ppm) 
     CO        Carbon Monoxide   (pct of Volume) 
     CO2       Carbon Dioxide    (pct of Volume) 
     DAY       Test Day:   1,2,...,13 
     REP       Replicate:  1,2,3,4   
     DEV       Device:     1 = Present, 0 = Absent
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c63.dat:

day  rep  dev       hc      co2      co    
  1    1    0     8.24    14.40    0.23
  1    2    0    20.20    16.27    0.32
  1    3    0    12.48    17.11    0.12
  1    4    0    20.27    15.53    0.32
  2    1    0     7.73    14.52    0.06
  2    2    0    13.10    16.45    0.05
  2    3    0    12.13    12.84    0.20
  2    4    0    10.03    13.84    0.12
  3    1    1     4.83    15.29    0.11
  3    2    1     4.33    13.46    0.16
  3    3    1     7.18    14.10    0.14
  3    4    1     5.51    16.55    0.05
  4    1    1     3.43    14.05    0.07
  4    2    1     9.16    13.84    0.23
  4    3    1     4.50    14.10    0.16
  4    4    1     7.06    11.92    0.17
  5    1    1    10.80    13.67    0.07
  5    2    1    10.23    14.80    0.09
  5    3    1     7.86    13.64    0.16
  5    4    1     5.73    16.38    0.00
  6    1    1    17.32    14.18    0.24
  6    2    1    23.08    14.23    0.01
  6    3    1     7.33    11.14    0.08
  6    4    1     5.00    13.96    0.20
  7    1    1    21.51    13.89    0.25
  7    2    1    24.70    14.42    0.16
  7    3    1    29.44    13.11    0.27
  7    4    1    27.91    13.59    0.17
  8    1    1     7.84    16.13    0.23
  8    2    1     4.72    16.32    0.10
  8    3    1     2.27    15.84    0.20
  8    4    1     2.98    15.52    0.30
  9    1    1    18.40    15.39    0.08
  9    2    1    13.91    15.55    0.02
  9    3    1    13.07    15.84    0.19
  9    4    1     7.35    15.34    0.11
 10    1    1     0.90    16.38    0.06
 10    2    1     2.66    15.28    0.10
 10    3    1     0.71    14.69    0.13
 10    4    1     0.17    15.31    0.16
 11    1    1    15.74    16.46    0.21
 11    2    1     9.62    14.79    0.14
 11    3    1    13.87    14.71    0.07
 11    4    1    11.62    13.47    0.13
 12    1    0    18.08    15.28    0.30
 12    2    0    11.16    15.07    0.11
 12    3    0    10.76    16.90    0.01
 12    4    0     5.22    15.19    0.11
 13    1    0    13.63    14.98    0.21
 13    2    0    14.00    14.21    0.21
 13    3    0    14.04    14.14    0.06
 13    4    0    12.50    13.62    0.14