Term
| Cormack-Jolly-Seber Model |
|
Definition
Estimate survival rate
based on recapture and/or resighting of marked
individuals (fates are not known for all individuals,
because p < 1). |
|
|
Term
|
Definition
Estimate survival rate when fates
(i.e., alive or dead) of individuals can be determined
with certainty (probability of detection, p = 1). |
|
|
Term
|
Definition
Estimate survival rate and
other parameters based on recoveries of tags from
harvested individuals (fates are not known for all
individuals, because recovery rate < 1). |
|
|
Term
| Estimating the Probability of Survival |
|
Definition
|
|
Term
|
Definition
* A group of animals are radiomarked @beginning of study and then observed at the end of some interval.
maximum likelihood estimate:
Š= yi/n
yi: days
variance: (where n>30)
var(Š) = Š (1-Š)/n
**Issue: info is lost when only option is dead or alive**
survival rate is not constant over time |
|
|
Term
Capture history
*1st position* |
|
Definition
1: the individual is known to be alive at the start of interval
0: the individual is not yet tagged or has been censored |
|
|
Term
Capture history
*2nd position* |
|
Definition
0: the individual survived to the end of the interval
1: the individual died sometime during interval |
|
|
Term
|
Definition
The loss of potential observations, because the fate of an individual is not known for some occasion or multiple occasions.
Due to:
-radio failure
- emigration
- Termination of study before animals die |
|
|
Term
Known Fate model
ln(likelihood function)
|
|
Definition
| ln(L(S/ni)=Σ (frequency)*ln(probability) |
|
|
Term
5 Assumptions of
Known Fate Model |
|
Definition
1. The sample is representative of the sample studied.
2. "Marked" animals are independent samples.
3. Survival rate is homogenous across individuals
(rate can vary over time)
4. Detection probability is 1 at each occasion
5. Censoring is independent of the fate of the animal. Any animal not located must be as likely to be alive as dead. |
|
|
Term
|
Definition
BIDE= true abundance
bide= per capita rates |
|
|
Term
Encounter History
10 10 10 10 |
|
Definition
Probability
S1 S2 S3 S4
Interpretation
Tagged on occasion 1 and survived to the end of the study
|
|
|
Term
Encounter History
10 10 11 00 |
|
Definition
Probability
S1 S2 (1-S3)
Interpretation
Tagged at occasion 1, known alive during 2nd interval, died during 3rd interval |
|
|
Term
Encounter History
10 11 00 00 |
|
Definition
Probability
S1 (1-S2)
Tagged on occasion 1, died during 2nd interval |
|
|
Term
Encounter History
11 00 00 00 |
|
Definition
Probability
(1-S1)
Tagged on occasion 1 and died during the 1st interval |
|
|
Term
Encounter History
10 00 00 10 |
|
Definition
Probability
S1 S4
Tagged on occasion 1, censored for intervals 2 and 3 (not detected) and re-inserted into the study on occasion 4 |
|
|
Term
Encounter History
00 00 10 11 |
|
Definition
Probability
S3 (1-S4)
Tagged on occasion 3, died during the 4th interval |
|
|
Term
Encounter History
10 00 00 00 |
|
Definition
Probability
S1
Tagged on occasion 1, known alive at the end of the 1st interval, but not released at occasion 2 and therefore censored after the first interval |
|
|
