  The phenomenon of pulsar nulling, observed as the temporary inactivity of a
pulsar, remains poorly understood both observationally and theoretically. Most
observational studies that quantify nulling employ a variant of Ritchings
(1976)'s algorithm which can suffer significant biases for pulsars where the
emission is weak. Using a more robust mixture model method, we study pulsar
nulling in a sample of 22 recently discovered pulsars, for which we publish the
nulling fractions for the first time. These data clearly demonstrate biases of
the former approach and show how an otherwise non-nulling pulsar can be
classified as having significant nulls. We show that the population-wide
studies that find a positive correlation of nulling with pulsar
period/characteristic age can similarly be biased because of the bias in
estimating the nulling fraction. We use our probabilistic approach to find the
evidence for periodicity in the nulls in a subset of three pulsars in our
sample. In addition, we also provide improved timing parameters for 17 of the
22 pulsars that had no prior follow-up.
