Hi, I'm a bit confused with the different 'birth' derived POPAN parameters. I've looked through chapter 12 of the mark book and also read the Schwarz and Arnason 1996 paper but haven't had much luck.
What is the difference between BiGross and B* Gross births (which is the same as B-hat?) ? Could someone provide the correct definitions please?
The definitions from Schwarz and Arnason 1996 are:
-Bi number of animals that enter after sample time i and survive to sample time i + 1,
i = O. ... , k - 1. The Bi are referred to as the net births. Bo is defined as the number
of animals alive just prior to the first sample time.
-Bi* gross number of animals that enter between sampling occasions i and i + 1. These include
animals that enter and die before the next sampling occasion.
I can't seem to find a definition of Bi Gross anywhere.
Also, with Net births, each group is consistent across years. Does this mean that net births are, for example, 5.75 between i and i+1 or is this across the whole of the study period?
>results$derived
$`B* Gross Births`
estimate se lcl ucl
6 6.356789e+00 7.441877e-01 5.057372e+00 7.990071e+00
7 5.910371e+00 6.636054e-01 4.746143e+00 7.360183e+00
8 6.983769e+00 8.504516e-01 5.505715e+00 8.858618e+00
9 6.045344e+00 6.892532e-01 4.838198e+00 7.553677e+00
10 6.696976e+00 8.443284e-01 5.235804e+00 8.565920e+00
16 7.016028e+00 1.448408e+00 4.701040e+00 1.047101e+01
17 4.768665e+00 9.751729e-01 3.207053e+00 7.090675e+00
18 8.821659e+00 1.820427e+00 5.911833e+00 1.316371e+01
19 5.624325e+00 1.245842e+00 3.662444e+00 8.637137e+00
20 8.095871e+00 1.822230e+00 5.236397e+00 1.251684e+01
$`B Net Births`
estimate se lcl ucl
6 5.747887e+00 6.318783e-01 4.636741e+00 7.125307e+00
7 5.747887e+00 6.318783e-01 4.636741e+00 7.125307e+00
8 5.747887e+00 6.318783e-01 4.636741e+00 7.125307e+00
9 5.747887e+00 6.318783e-01 4.636741e+00 7.125307e+00
10 5.747887e+00 6.318783e-01 4.636741e+00 7.125307e+00
16 3.226884e+00 3.547387e-01 2.603083e+00 4.000172e+00
17 3.226884e+00 3.547387e-01 2.603083e+00 4.000172e+00
18 3.226884e+00 3.547387e-01 2.603083e+00 4.000172e+00
19 3.226884e+00 3.547387e-01 2.603083e+00 4.000172e+00
20 3.226884e+00 3.547387e-01 2.603083e+00 4.000172e+00
>popan.derived
$BiGross
sex injury occasion estimate se
2 M major 1 28.26056 3.159481e+00
2.1 M major 2 34.61735 2.462664e+00
2.2 M major 3 40.52772 1.819467e+00
2.3 M major 4 47.51149 1.125427e+00
2.4 M major 5 53.55684 6.113182e-01
2.5 M major 6 60.25381 7.421704e-01
5 M none 1 15.86558 1.773744e+00
5.1 M none 2 22.88161 1.574671e+00
5.2 M none 3 27.65027 1.656681e+00
5.3 M none 4 36.47193 2.821646e+00
5.4 M none 5 42.09626 3.581685e+00
5.5 M none 6 50.19213 4.992593e+00
Apologies if this has already been posted, I couldn't find it!
Many thanks in advance,
Jess