  Merging in the form of a mandatory lane-change is an important issue in
transportation research. Even when safely completed, merging may disturb the
mainline traffic and reduce the efficiency or capacity of the roadway. In this
paper, we consider a Stackelberg game-theoretic driver behavior model where the
so-called utilities or payoffs reflect the merging vehicle's aggressiveness as
it pertains the decision to merge as the situation stands or to accelerate,
decelerate prior to the actual lane-change maneuver. The interaction of the
merging vehicle with the mainline traffic is also considered whereby the
combination of aggressiveness of the respective vehicles leads to both
longitudinal and lateral disturbances to the mainline flow as well as
subsequent reduction in the roadway throughput. The present study shows in
semi-quantitative form that this impact depends on the level of aggressiveness
of the merging and mainline vehicles, leading to the potential use of this
model in traffic flow analysis and autonomous driving.
