dataset=popcorn
begin description
Data from Myers, Montgomery and Vining (2002) Generalized Linear Models 
with Applications in Engineering and the Sciences, Wiley.
end description
begin variables
col 0 = temp = temperature
col 1 = oil = amount of oil
col 2 = time = popping time
col 3 = y = number of inedible kernels of popcorn
end variables
begin data
7  4  90  24
5  3  105 28
7  3  105 40
7  2  90  42
6  4  105 11
6  3  90  16
5  3  75  126
6  2  105 34
5  4  90  32
6  2  75  32
5  2  90  34
7  3  75  17
6  3  90  30
6  3  90  17
6  4  75  50