hello there,
I'm an R beginner and got plunged into this. I guess my attempts are hopeless so far, so I won't even show them.
I want to write a loop, which prints all erroneous values. My definition of erroneous: If the current counts (partridge counts in a hunting district) differ from last years counts by more than 50 percent and absolut values differ by more than 5 animals I want r to print these values.
I have a grouping variable District "D", the year "Y" and the counts "C".
example table:
D Y C
a 2005 10
a 2006 0
a 2007 9
b 2005 1
b 2006 0
b 2007 1
c 2005 5
c 2006 NA
c 2007 4
Although the difference in a and b is 100 percent I would doubt a's population breakdown, whereas District b is credible. To confuse things I want the loop to skip missing values and instead look at the year after.
Any help is very much appreciated!
Thanks,
Katrin