  We present here two examples of stochastic modelings of social phenomena. The
first topic is pedestrian counter flow. Two groups of model pedestrians move in
opposite directions and create congestions. It will be shown that this
congestion becomes worst where individuals are given certain stochastic freedom
to avoid another in front compared to the case that they are bound to more
strict rules. The second example model tournaments. We present here a rather
unexpected feature of tournaments that the probability to reach the top
position is higher than that of finishing up at lower positions for not only
the number one ranked player, but also for a range of top players. This
"inversion characteristics" are shown to be observed with simple mathematical
model tournaments as well as in the real tournaments.
