  In this work we investigate an unusual transport phenomenon observed in
two-dimensional electron gas under integer quantum Hall effect conditions. Our
calculations are based on the screening theory, using a semi-analytical model.
The transport anomalies are \emph{dip} and overshoot effects, where the Hall
resistance decreases (or increases) unexpectedly at the quantized resistance
plateaus intervals. We report on our numerical findings of the \emph{dip}
effect in the Hall resistance, considering GaAs/AlGaAs heterostructures in
which we investigated the effect under different experimental conditions. We
show that, similar to overshoot, the amplitude of the dip effect is strongly
influenced by the edge reconstruction due to electrostatics. It is observed
that the steep potential variation close to the physical boundaries of the
sample results in narrower incompressible strips, hence, the experimental
observation of the dip effect is limited by the properties of these current
carrying strips. By performing standard Hall resistance measurements on gate
defined narrow samples, we demonstrate that the predictions of the screening
theory is in well agreement with our experimental findings.
