by JOHN C. DRAKOPOULOS
In the present paper we considered how effective the difference in the b value
for foreshocks would be for predicting earthquakes, if indeed differences in b values
do exist. It was found that the correct judgement is more probable as the ratios bf/ba are
smaller and as the number of foreshocks is larger. We applied the method for
the cases of fore and aftershock sequences on and
around Euboea Island. Additionally we tested the difference in b-value
applying the well-known 
-distribution
test as was suggested by Utsu and we tried also to test the significance of
the b-values for fore and aftershocks on and around
Euboea Island making use of Student's t test as Miyamura applied the method.