Below you see the full data set ashina (from the ISwR package). Convert this data set to the long format so the two vas measurements become one variable called treat. Call this data set ashina_long (see help(ashina) for more information on the data).

 

   vas.active vas.plac grp
1        -167     -102   1
2        -127      -39   1
3         -58       32   1
4        -103       28   1
5         -35       16   1
6        -164      -42   1
7          -3      -27   1
8          25      -30   1
9         -61      -47   1
10        -45        8   1
11        -38       12   2
12         29       11   2
13          2       -9   2
14        -18       -1   2
15        -74        3   2
16        -72      -36   2

 

(from: Dalgaard, 2008, Introductory Statistics with R, Springer)