A Bayesian Network Modeling Approach to Forecasting the 21st Century Worldwide Status of Polar Bears - Arctic Sea Ice Decline: Observations, Projections, Mechanisms, and Implications - page 242

Table A1. (continued)

Node
Name

Node Title Node Description States

(2020-2029)
mid century
(2045-2055)
late century
(2070-2080)
end of century
(2090-2099)

R GCM_minimum

ensemble_mean
GCM_maximum
satellite
a Output nodes here include the Numerical Response and Distribution Response nodes that provide summary output conditions.
b U.S. Fish and Wildlife Service (USFWS) lists five listing factors. Listing factor D pertains to inadequacy of existing regulatory mecha-
nisms, and was not included in the BN population stressor model because it does not correspond to any specific environmental stressor.
c These two nodes are included in the model to help denote the basis for a given model run. They are not included as environmental stress-
ors per se.

GCM run The states for this node correspond to the data source (either “satellite” for year −10

and 0 runs) and GCM modeling scenario (minimum, ensemble mean, or maximum)
basis for a given condition.

Table B1. Node A: Foraging habitat Value

Value of Foraging habitat

Node G:
Relocation
Possible

APPENDIX B: PROBABIlITy TABlES FOR EACh
NODE IN ThE BAyESIAN NETWORk MODEl

Node S1: Foraging
habitat Character

Same as
Now Better Worse

More optimal yes 0.7 0.3 0.0

Tables B1-B19 are probability tables for each node in the
BN model. (These were generated in the Netica® software.)
Not included here are all input nodes (yellow coded nodes in
Plate 3) because each of their prior probability tables was set
to uniform distributions.

More optimal no 0.2 0.6 0.2

Same as now yes 0.1 0.8 0.1

Same as now no 0.0 0.8 0.2

less optimal yes 0.0 0.3 0.7

less optimal no 0.0 0.0 1.0

Table B2. Node A1: Factor B Overutilization

Node A6:
Factor E—Other

level of Overutilization

Node E:

Intentional
Takes

Factors (Natural
or Man-Made)

Same as
Now Fewer More

Increased improvement 0.0 0.4 0.6

Increased no effect 0.0 0.0 1.0

Increased minor restriction 0.0 0.0 1.0

Increased major restriction 0.0 0.0 1.0

Same as now improvement 1.0 0.0 0.0

Same as now no effect 0.0 1.0 0.0

Same as now minor restriction 0.0 0.6 0.4

Same as now major restriction 0.0 0.3 0.7

Decreased improvement 1.0 0.0 0.0

Decreased no effect 1.0 0.0 0.0

Decreased minor restriction 0.0 0.8 0.2

Decreased major restriction 0.0 0.6 0.4