  The diagonal conductivity $\sigma_{xx}$ was measured in the Corbino geometry
in both integer and fractional quantum Hall effect (QHE). We find that peak
values of $\sigma_{xx}$ are approximately equal for transitions in a wide range
of integer filling factors $3<\nu<16$, as expected in scaling theories of QHE.
This fact allows us to compare peak values in the integer and fractional
regimes within the framework of the law of corresponding states.
