Reliability of Seismograph Stations

Abstract

I SHOULD agree with Mr. Hayes that not much importance should be attached to the difference between Wellington, and Christchurch. The standard error of a reliability r based on n observations is ; then with my data the results are Wellington 0.33±0.10, Christchurch 0.50±0.18. This is for all earthquakes recorded at the stations. For Pacific earthquakes alone, I get Wellington 0.36±0.13, Christchurch 0.56±0.19. The difference is therefore not more than might be attributed to random sampling. On the other hand, we may notice that there were three times as many readings of P at Wellington as at Christehurch, though in most cases the amplitude of the motion of the ground must have been about the same, and many of the inferior observations at Wellington refer to earthquakes when Christchurch failed to record P at all.