Class presentation (2 Oct)

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Class presentation (2 Oct)
• What are the 1-2 most
important questions that
the paper is trying to
answer?
• What is the approach used
to answer that question?
• What are the assumptions,
implicit or explicit,
underlying the approach?
• What does the paper infer
(re: point 1)
• Which commandment(s)
from Houle et al. might the
authors have broken?
• If any commandments are
broken, do you think there
inference holds?
• How might you improve on
the approach to make
better inference?
Class presentation (2 Oct)
Purposes
• Apply parts of what we have
discussed during this course
– thinking about assumptions
and whether inference might
hold.
– are models being compared
or are we comparing
strawman hypotheses.
– are the numbers presented
appropriate
Practice
• Extracting important information
(quickly)
• Presenting information simply
Practical info
• 10 minutes presentation with 5
minutes for discussion
• One page summary to be sent
around class
• Postdocs, Let me know if you are
doing this
Extinction: Group rates: q
Traditional methods for
estimating e.g. extinction rates
•
Face value
•
Survivorship analyses
– Dynamic survivorship (Raup)
– Cohort survivorship (Raup)
– FreqRat (Raup and Foote)
•
Within time interval rates (Foote, Alroy)
•
Sampling standardized rates (Alroy)
Extinction:
Capture recapture approaches
Day 1: catch 10 rats, put tags on them
Day 2: catch rats in the same place. 2 had your tags, but 8 didn’t
What is the capture probability?
2/10=0.2
How many rats are there in that “place?”
50
𝒎𝒂𝒓𝒌𝒆𝒅 𝑫𝒂𝒚 𝟐
𝒎𝒂𝒓𝒌𝒆𝒅 𝑫𝒂𝒚𝟏
=
𝒕𝒐𝒕𝒂𝒍 𝒇𝒐𝒓 𝑫𝒂𝒚𝟐 𝑬𝒔𝒕𝒊𝒎𝒂𝒕𝒆𝒅 𝑻𝒐𝒕𝒂𝒍
Motivation
• Origination and extinction
– Trends, drivers, correlates
• Diversity, occupancy
– Trends, drivers, correlates
• Preservation/sampling is a mostly a nuisance
– Incomplete sampling is universal
– We can try to account for some sources (e.g. uneven no. of samples,
control for facies, mineralogy of groups)
– Many unknown factors, heterogeneous
Time intervals
Taxon
1
2
3
4
5
6
7
8
A
0
0
1
1
0
0
1
0
B
0
1
0
0
0
0
0
0
C
0
0
0
0
0
1
1
1
D
1
0
1
1
0
1
0
0
E
0
0
0
1
0
0
1
1
F
0
1
0
0
1
1
0
1
G
0
0
0
1
0
1
1
0
H
0
0
0
0
0
1
1
0
I
0
0
1
0
1
1
0
1
J
1
0
0
0
0
0
0
0
K
0
0
0
0
1
0
1
1
L
0
0
1
1
0
0
0
0
M
0
1
0
1
1
0
0
0
N
1
1
0
0
1
0
1
0
O
0
0
0
1
0
1
1
1
P
0
0
1
0
0
0
0
0
Q
0
0
0
0
0
0
1
0
R
0
0
1
0
1
1
0
1
S
0
0
0
0
1
0
0
1
T
0
0
0
1
0
0
0
0
2. CMR Thinking
1 of 25
Encounter or Detection Histories
Time
interval
1
2
3
4
5
6
7
8
L
0
1
1
0
0
0
0
0
M
0
1
0
1
1
0
0
0
Encounter/detection histories
- Series of ones and zeros
- Ones are taken as true presences
- Two types of zeros
- Not sampled
- Not sampled or truly absent
2. CMR Thinking
Time intervals
Detection
probability
Taxon
1
2
3
4
5
6
7
8
A
0
0
1
1
0
0
1
0
B
0
1
0
0
0
0
0
0
C
0
0
0
0
0
1
1
1
D
1
0
1
1
0
1
0
0
E
0
0
0
1
0
0
1
1
F
0
1
0
0
1
1
0
1
G
0
0
0
1
0
1
1
0
H
0
0
0
0
0
1
1
0
I
0
0
1
0
1
1
0
1
J
1
0
0
0
0
0
0
0
K
0
0
0
0
1
0
1
1
L
0
0
1
1
0
0
0
0
M
0
1
0
1
1
0
0
0
N
1
1
0
0
1
0
1
0
O
0
0
0
1
0
1
1
1
P
0
0
1
0
0
0
0
0
Q
0
0
0
0
0
0
1
0
R
0
0
1
0
1
1
0
1
S
0
0
0
0
1
0
0
1
T
0
0
0
1
0
0
0
0
pˆ 6  5 /10  0.5
2. CMR Thinking
Time intervals
Taxon
1
2
3
4
5
6
7
8
A
0
0
1
1
0
0
1
0
B
0
1
0
0
0
0
0
0
C
0
0
0
0
0
1
1
1
D
1
0
1
1
0
1
0
0
E
0
0
0
1
0
0
1
1
Sˆ6  s6 / pˆ 6  8 / 0.5  16
Estimated
no. taxa
F
0
1
0
0
1
1
0
1
G
0
0
0
1
0
1
1
0
H
0
0
0
0
0
1
1
0
I
0
0
1
0
1
1
0
1
J
1
0
0
0
0
0
0
0
K
0
0
0
0
1
0
1
1
L
0
0
1
1
0
0
0
0
M
0
1
0
1
1
0
0
0
N
1
1
0
0
1
0
1
0
O
0
0
0
1
0
1
1
1
P
0
0
1
0
0
0
0
0
Q
0
0
0
0
0
0
1
0
R
0
0
1
0
1
1
0
1
S
0
0
0
0
1
0
0
1
T
0
0
0
1
0
0
0
0
2. CMR Thinking
Time intervals
Extinction
probability
Taxon
1
2
3
4
5
6
7
8
A
0
0
1
1
0
0
1
0
B
0
1
0
0
0
0
0
0
C
0
0
0
0
0
1
1
1
D
1
0
1
1
0
1
0
0
0
0
1
0
0
1
1
1
0
0
1
1
0
1
0
0
1
0
1
1
0
0
0
0
0
1
1
0
0
1
0
1
1
0
1
0
0
0
0
0
0
0
0
0
0
1
0
1
1
0
1
1
0
0
0
0
1
0
1
1
0
0
0
1
0
0
1
0
1
0
0
0
1
0
1
1
1
ˆ5  1F  ( Mˆ / s5 )
0
E
'
0
6
0
G
m / p0ˆ 6
 1 J (
)
1
s
5 0
K
H
I
L
'
6
0
0
3 / 0.50
 1 N(
)
1
7 0
O
M
P
0
0
1
0
0
0
0
0
Q
0
0
0
0
0
0
1
0
R
0
0
1
0
1
1
0
1
S
0
0
0
0
1
0
0
1
T
0
0
0
1
0
0
0
0
2. CMR Thinking
Time intervals
Extinction
probability
Taxon
1
2
3
4
5
6
7
8
A
0
0
1
1
0
0
1
0
B
0
1
0
0
0
0
0
0
C
0
0
0
0
0
1
1
1
D
1
0
1
1
0
1
0
0
0
0
1
0
0
1
1
1
0
0
1
1
0
1
0
0
1
0
1
1
0
0
0
0
0
1
1
0
0
1
0
1
1
0
1
0
0
0
0
0
0
0
0
0
0
1
0
1
1
0
1
1
0
0
0
0
1
0
1
1
0
0
0
1
0
0
1
0
1
0
0
0
1
0
1
1
1
ˆ5  1F  ( Mˆ / s5 )
0
E
'
0
6
0
G
m / p0ˆ 6
 1 J (
)
1
s
5 0
K
H
I
L
'
6
0
0
3 / 0.50
 1 N(
)
1
16
7 0
O
M
P
0
0
1
0
0
0
0
0
Q
0
0
0
0
0
0
1
0
R
0
0
1
0
1
1
0
1
S
0
0
0
0
1
0
0
1
T
0
0
0
1
0
0
0
0
Encounter/Detection Probability
p
2. CMR Thinking
Representing detection/encounter histories
1
2
3
4
5
6
7
8
0
0
1
0
1
1
0
0
p4
p5
p6
p7
p8
ε3
eh = 0 0 1 0 1 1 0 0
ε4
ε5
ε6
ε7
CJS model
Pr(eh = 0 0 1 0 1 1 0 0 | initial encounter in interval 3) =
Detection
probabilities
Extinction
probabilities
2. CMR Thinking
Representing detection/encounter histories
1
2
3
4
5
6
7
8
0
0
1
0
1
1
0
0
p4
p5
p6
p7
p8
ε3
ε4
ε5
ε6
ε7
Detection
probabilities
Extinction
probabilities
eh = 0 0 1 0 1 1 0 0
Pr(eh = 0 0 1 0 1 1 0 0 | initial encounter in interval 3) =
(1-ε3)(1-p4) (1-ε4)p5 (1-ε5)p6 [ε6 + (1-ε6)(1-p7){ε7+(1- ε7)(1- p8)}]
2. CMR Thinking
Representing detection/encounter histories
1
2
3
4
5
6
7
8
0
0
1
0
1
1
0
0
p4
p5
p6
p7
p8
ε3
ε4
ε5
ε6
ε7
Detection
probabilities
Extinction
probabilities
eh = 0 0 1 0 1 1 0 0
Pr(eh = 0 0 1 0 1 1 0 0 | initial encounter in interval 3) =
(1-ε3)(1-p4) (1-ε4)p5 (1-ε5)p6 [ε6 + (1-ε6)(1-p7){ε7+(1- ε7)(1- p8)}]
2. CMR Thinking
Representing detection/encounter histories
1
2
3
4
5
6
7
8
0
0
1
0
1
1
0
0
p4
p5
p6
p7
p8
ε3
ε4
ε5
ε6
ε7
Detection
probabilities
Extinction
probabilities
eh = 0 0 1 0 1 1 0 0
Pr(eh = 0 0 1 0 1 1 0 0 | initial encounter in interval 3) =
(1-ε3)(1-p4) (1-ε4)p5 (1-ε5)p6 [ε6 + (1-ε6)(1-p7){ε7+(1- ε7)(1- p8)}]
2. CMR Thinking
Representing detection/encounter histories
1
2
3
4
5
6
7
8
0
0
1
0
1
1
0
0
p4
p5
p6
p7
p8
ε3
ε4
ε5
ε6
ε7
Detection
probabilities
Extinction
probabilities
eh = 0 0 1 0 1 1 0 0
Pr(eh = 0 0 1 0 1 1 0 0 | initial encounter in interval 3) =
(1-ε3)(1-p4) (1-ε4)p5 (1-ε5)p6 [ε6 + (1-ε6)(1-p7){ε7+(1- ε7)(1- p8)}]
2. CMR Thinking
Representing detection/encounter histories
1
2
3
4
5
6
7
8
0
0
1
0
1
1
0
0
p4
p5
p6
p7
p8
ε3
ε4
ε5
ε6
ε7
Detection
probabilities
Extinction
probabilities
eh = 0 0 1 0 1 1 0 0
Pr(eh = 0 0 1 0 1 1 0 0 | initial encounter in interval 3) =
(1-ε3)(1-p4) (1-ε4)p5 (1-ε5)p6 [ε6 + (1-ε6)(1-p7){ε7+(1- ε7)(1- p8)}]
”sampling” and vital parameters are both explicit!
3. Likelihood framework
We have detection histories – now what?
Pr(eh = 0 0 1 0 1 1 0 0) =
(1-ε3)(1-p4) (1-ε4)p5 (1-ε5)p6 [ε6 + (1-ε6)(1-p7){ε7+(1- ε7)(1- p8)}]= H1
Likelihood (parameters|data) = H1No. cases H2No. cases HxNo. cases
0001010010
0010001101
0101010100
1001000000
0001010111
0011101000
10
3
4
18
2
1
3
No. cases
3. Likelihood framework
Likelihood of Detection histories
1. Estimate parameters (by maximizing the likelihood)
2. Estimate uncertainty in parameters
3. Compare models
• e.g. same or different p’s or ε’s
• e.g. with or without covariates (important factors that you
think might influence p and ε)
i.
Akaike Information Criteria, AIC
ii.
classical hypothesis testing
iii.
extendable to Bayesian approaches
4. Good statistical properties
4. Assumptions
Assumptions of the CJS model
1. After initial encounters, detection/encounter probabilities are
equal for all taxa in the data/group of interest
2. After initial encounters, extinction probabilities for all taxa are
equal
3. Sampling intervals are short relative to the time over which
extinction is to be estimated
4. The fate of each taxon (with respect to extinction and
encounter) is independent of the fate of every other taxon
4. Assumptions
Assumptions of the CJS model
1. After initial encounters, detection/encounter probabilities are
equal for all taxa in the data/group of interest
• Taxon specific covariates
2. After initial encounters, extinction probabilities for all taxa are
equal
3. Sampling intervals are short relative to the time over which
extinction is to be estimated
4. The fate of each taxon (with respect to extinction and
encounter) is independent of the fate of every other taxon
4. Assumptions
Assumptions of the CJS model
1. After initial encounters, detection/encounter probabilities are
equal for all taxa in the data/group of interest
2. After initial encounters, extinction probabilities for all taxa are
equal
• Taxon specific covariates
3. Sampling intervals are short relative to the time over which
extinction is to be estimated
4. The fate of each taxon (with respect to extinction and
encounter) is independent of the fate of every other taxon
4. Assumptions
Assumptions of the CJS model
1. After initial encounters, detection/encounter probabilities are
equal for all taxa in the data/group of interest
2. After initial encounters, extinction probabilities for all taxa are
equal
3. Sampling intervals are short relative to the time over which
extinction is to be estimated
• Simulations show that this is not a big problem
4. The fate of each taxon (with respect to extinction and
encounter) is independent of the fate of every other taxon
4. Assumptions
Assumptions of the CJS model
1. After initial encounters, detection/encounter probabilities are
equal for all taxa in the data/group of interest
2. After initial encounters, extinction probabilities for all taxa are
equal
3. Sampling intervals are short relative to the time over which
extinction is to be estimated
4. The fate of each taxon (with respect to extinction and
encounter) is independent of the fate of every other taxon
• Corrections for over-dispersion
• Co-occurrence analyses
5. Covariate modeling
Covariate modeling
• A way to include factors or variables that may be important in
explaining variation in the parameters (e.g. extinction,
sampling) you are interested in
• Allows us to compare models with different [or no] covariates
(Model comparison and selection)
• models to compare

ε(constant)p(time-varying)

ε(time-varying)p(sea-levels)
5. Covariate modeling
Covariate modeling via link functions
 i ,t
logit( i ,t )  log(
)   0  1 xi   2 yt
1   i ,t
Taxon specific covariates
•size
•minerology
•taxonomic group
5. Covariate modeling
Covariate modeling via link functions
 i ,t
logit( i ,t )  log(
)   0  1 xi   2 yt
1   i ,t
Time specific covariates
•Duration of bin
•Sea-level
•Temperature
5. Covariate modeling
Covariate modeling via link functions
 i ,t
logit( i ,t )  log(
)   0  1 xi   2 yt
1   i ,t
0  1 xi   2 yt
e
 i ,t 
0  1 xi   2 yt
1 e
6. MARK
MARK demo
• Follow supplement from Liow and Nichols
• Rexercise3
7. Coda
Why Capture-Mark-Recapture (CMR) ?
p 1
p
•
Detection probability
•
Separating between
- probability of detection (given presence)
- probability of the parameters in question
(e.g. survivorship, origination, occupancy, immigration)
and derived parameters such as species richness/diversity
The probability of detection or sampling is sometimes only a nuisance but sometimes
interesting in itself.
•
•
Covariates can be EASILY included in models for both vital parameters and
sampling/detection estimates.
Covariates can be modeled at a variety of levels (e.g. group factors, individual traits,
temporal characteristics)
References
• Reading: Liow, L. H. and J. D. Nichols (2010).
Estimating rates and probabilities of origination and
extinction using taxonomic occurrence data:
Capture-recapture approaches. Short Courses in
Paleontology: Quantitative Paleobiology. G. Hunt
and J. Alroy, Paleontological Society: 81-99 (plus
supplement which will help with the MARK
exercise)
• Mark Book (Chap 3 most relevant for today’s
lecture)
http://www.phidot.org/software/mark/docs/book/
Assignment
• Use the previous data you downloaded and
arrange it in a matrix that will be suitable for
data analyses in MARK. Using MARK or
RMARK run a few reasonable CJS models on
the data
• Write a short note on your observations
Per capita origination and extinction rates
bL
bt
FL
Ft
Foote, M. 2000. Origination and extinction components of taxonomic diversity: general problems.
Paleobiology 26:74-102.
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