  Pulsar nulling is a phenomenon of sudden cessation of pulse emission for a
number of periods. The nulling fraction was often used to characterize the
phenomenon. We propose a new method to analyse pulsar nulling phenomenon, by
involving two key parameters, the nulling degree, $\chi$, which is defined as
the angle in a rectangular coordinates for the numbers of nulling periods and
bursting periods, and the nulling scale, $ N $, which is defined as the
effective length of the consecutive nulling periods and bursting periods. The
nulling degree $\chi$ can be calculated by $\tan \chi = N_{\rm nulling} /
N_{\rm bursting} $ and the mean is related to the nulling fraction, while the
nulling scale, $ N $, is also a newly defined fundamental parameter which
indicates how often the nulling occurs. We determined the distributions of
$\chi$ and $ N $ for 10 pulsars by using the data in literature. We found that
the nulling degree $\chi$ indicates the relative length of nulling to that of
bursting, and the nulling scale $ N $ is found to be related to the derivative
of rotation frequency and hence the loss rate of rotational energy of pulsars.
Their deviations reflect the randomness of the nulling process.
