Dear all,

I have a problem with calculating UD areas: I calculated UDs by 
kernelbb(). When I use the getverticeshr command and after that the 
kernel.area command, the results differ. Does anyone see my mistake?

Thanks a lot and best regards,
Anna


> head(dcol[,c(1:11,17,25:27)])
         date day month year hour minute second time_sec time_diff latitude longitude
1 13.05.2011  13     5 2011   21     11     33    76293       186 54.70463  8.349938
2 13.05.2011  13     5 2011   21     14     37    76477       184 54.70479  8.349722
3 13.05.2011  13     5 2011   21     17     40    76660       183 54.70548  8.344133
4 13.05.2011  13     5 2011   21     20     44    76844       184 54.71007  8.338260
5 13.05.2011  13     5 2011   21     23     48    77028       184 54.72099  8.320427
6 13.05.2011  13     5 2011   21     26     52    77212       184 54.73233  8.312453
    bird_id                 cet   xKoord  yKoord
1 HA1_2011 2011-05-13 21:11:33 458111.9 6062117
2 HA1_2011 2011-05-13 21:14:37 458098.1 6062135
3 HA1_2011 2011-05-13 21:17:40 457738.7 6062216
4 HA1_2011 2011-05-13 21:20:44 457365.1 6062730
5 HA1_2011 2011-05-13 21:23:48 456227.9 6063956
6 HA1_2011 2011-05-13 21:26:52 455726.7 6065223



#### create ltraj elements:
##HA1_2011
ha111<-subset(dcol,bird_id=="HA1_2011")
ha111time <- ha111[, c("cet")]
ha111XY <- ha111[,c("xKoord", "yKoord")]
ha111ltraj <- as.ltraj(ha111XY, ha111time, id="HA1_2011")
ha111Liker <- liker (ha111ltraj, sig2=20, rangesig1=c(1,100) )
ha111Liker
head(ha111Liker)
ha111BbKern <- kernelbb(ha111ltraj, sig1=18.5405, sig2=20)

kernelcontoursha111_50  <- getverticeshr(ha111BbKern,lev=50, unout="km2")
# Object of class "SpatialPolygonsDataFrame" (package sp):

Number of SpatialPolygons:  1

Variables measured:
                  id     area
homerange homerange 6.055773

## kernel areas:
ha111area<-kernel.area(ha111BbKern, unout=c("km2"),percent=50) ## 0.9744107




	[[alternative HTML version deleted]]

