improbable.
If increases, I, and decreases, D, occur random
ly, the sequence of observed I's and D's would
have random order. A run of I's (or D's) is a
sequence (perhaps consisting of one element) of
adjacent I's (or D's) which cannot be lengthened;
i.e., the total number of runs is always one greater
than the number of changes from I to D or D to I.
If more runs of I's or D's are observed than would
be expected in a random sequence, then an increase
makes the following change more likely to be a
decrease and conversely. This IS what would be
expected on the hypothesis of density dependent
events