Statistical studies of the performance of cosmic ray recording instruments

A method is presented to determine the variance of statistical fluctuations in cosmic ray data derived from the neutron monitor, the duplex cubical counter telescope and the directional telescopes. The standard deviation of the error distribution from instruments at the cosmic ray stations at Uppsala, Murchison Bay and Mt. Wellington is estimated by the method. The results are compared with the Poisson distribution and it is stressed that the use of the Poisson distribution will give an underestimate. The results offer standard error calculations of cosmic ray data.