Method for determining a statistical measurement parameter for all frequencies of occurrence of a frequency of occurrence distribution of signal levels of a test signal registered in each case in several observation intervals, and for displaying in a time and/or frequency raster of a display device, having the following method steps: • determining frequencies of occurrence of registered signal levels of the test signal for each signal-level range and each value of the raster of the frequency of occurrence distribution in each observation interval by re-counting of the signal level, measured in the respective signal-level range and at the respective value of the raster in the respective observation interval, of the test signal in each observation interval, • buffering the determined frequencies of occurrence of the frequency of occurrence distribution at the end of each observation interval, • determining and re-buffering a statistical measurement parameter for each signal-level range and each value of the raster of the frequency of occurrence distribution at the end of each observation interval from the frequency of occurrence determined for the respective signal-level range and for the respective value of the raster in the respective observation interval, and all frequencies of occurrence determined and buffered in each case for the respective signal-level range and for the respective value of the raster in previous observation intervals, and • displaying the respective determined statistical measurement parameter instead of the respective determined frequency of occurrence on the display device for all frequencies of occurrence of zero, if, in the respective observation interval, a frequency of occurrence of zero is determined in each case for the respective signal-level range and for the respective value of the raster, wherein the statistical measurement parameter is the maximum or mean frequency of occurrence of signal levels of the test signal measured in each case within the respective signal-level range and at the respective value of the raster of the frequency of occurrence distribution from frequencies of occurrence counted respectively in all observation intervals of signal levels of the test signal measured in each case within the respective signal-level range and at the respective value of the raster of the frequency of occurrence distribution. • determining frequencies of occurrence of registered signal levels of the test signal for each signal-level range and each value of the raster of the frequency of occurrence distribution in each observation interval by re-counting of the signal level, measured in the respective signal-level range and at the respective value of the raster in the respective observation interval, of the test signal in each observation interval, • buffering the determined frequencies of occurrence of the frequency of occurrence distribution at the end of each observation interval, • determining and re-buffering a statistical measurement parameter for each signal-level range and each value of the raster of the frequency of occurrence distribution at the end of each observation interval from the frequency of occurrence determined for the respective signal-level range and for the respective value of the raster in the respective observation interval, and all frequencies of occurrence determined and buffered in each case for the respective signal-level range and for the respective value of the raster in previous observation intervals, and • displaying the respective determined statistical measurement parameter instead of the respective determined frequency of occurrence on the display device for all frequencies of occurrence of zero, if, in the respective observation interval, a frequency of occurrence of zero is determined in each case for the respective signal-level range and for the respective value of the raster, wherein the statistical measurement parameter is the maximum or mean frequency of occurrence of signal levels of the test signal measured in each case within the respective signal-level range and at the respective value of the raster of the frequency of occurrence distribution from frequencies of occurrence counted respectively in all observation intervals of signal levels of the test signal measured in each case within the respective signal-level range and at the respective value of the raster of the frequency of occurrence distribution.