Can someone explain me this spec.pgram effect?

 

Code:

 

period.6<-c(0,0,0,0,0,10,0,0,0,0,0,10,0,0,0,0,0,10,0,0,0,0,0,10,0,0,0,0,0,10
,0,0,0,0,0,10,0,0,0,0,0,10,0,0,0,0,0,10,0,0,0,0,0,10,0,0,0,0,0,10)

period.5<-c(0,0,0,0,0,10,0,0,0,0,10,0,0,0,0,0,0,10,0,0,0,0,10,0,0,0,0,0,0,10
,0,0,0,0,10,0,0,0,0,0,0,10,0,0,0,0,10,0,0,0,0,0,0,10,0,0,0,0,10,0)

 

par(mfrow=c(2,1))

 

spec.pgram(period.6, log="no")

spec.pgram(period.5, log="no")

 

 

The first series has period 6 and shows its periodicity in 1/6 and
harmonics. In the second series I was expecting to see a signal occurring at
frequency 1/5 but it does not. Can anybody explain me why? 

 

Thanks in advance,

 

Nuno

 

______________________________________________ 

Centro de Oceanografia - IO-FCUL, Portugal

Center for Quantitative Fisheries Ecology - ODU, USA

email: nmprista*@fc.ul.pt ; nprista*@odu.edu 

 


	[[alternative HTML version deleted]]

