Adding another association test.
Adding another association test.

- simulate correlated variables, each drawn from a possion distribution

- test whether algorithm with params (p=0.1, q=0.9, f=0.1) and 1000 samples
  detects (a) simulated correlations and (b) their lack thereof

- small fixes to deal with column names in data frame (1 vs. "1")

- fixed a few small typos along the way

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