R-script use dot identifier in formula
R-script use dot identifier in formula

http://stackoverflow.com/a/5251676/1287369

thekingofkings/urban-flow-analysis,thekingofkings/chicago-crime,thekingofkings/urban-flow-analysis,thekingofkings/chicago-crime,thekingofkings/chicago-crime,thekingofkings/urban-flow-analysis,thekingofkings/chicago-crime,thekingofkings/urban-flow-analysis,thekingofkings/chicago-crime,thekingofkings/chicago-crime,thekingofkings/urban-flow-analysis