An independent check of VAN's criteria for signal recognition

Abstract

In order to examine the generality of VAN's stated criteria for recognition of seismic electric signals (SES), an independent check of the original VAN geoelectric potential records has been made. (1) 338 anomalous changes were identified in three month of records (July 19–Oct. 18, 1988) of the Ioannina (IOA) station. After applying VAN's criteria, only 8 changes survived as possible SES. 7 of them coincided with anomalies used by the VAN group to issue successful predictions during that period. (2) A similar check of the IOA data was conducted for the 28.5 month period from April 30, 1988 to Sept. 15, 1990. 41 changes were selected as possible SES out of more than 3,000 anomalous changes. During this period, the VAN group issued 18 predictions. 14 of the SES used by the VAN group were identical to the SES we selected, while 4 were judged as noise. SESs common to both sets were generally stronger ones.