94
5 Handling Uncertainty and Sensitivity …
Table 5.1 Summary of assessments or calculations used as basis for classification in the sea surface.
Impact and impact time parameters
Main parameter A: Strength of knowledge (function where it is used)
B: Belief that the value may deviate from the average assumption (natural
variation of parameter)
C: Sensitivity of function to parameter (sensitivity index)
p beh
A Moderate/weak. Due to limited data and large natural variation it is difficult
to assign a specific p beh value. The assumption that behavioural factors will
affect p exp is strong
B Moderate
C Moderate
Comments/recommendations:
A higher value is conservative. Each VEC have three estimates (low,
intermediate, high), using high is most conservative. Alternative, use all to
obtain larger credible interval
Cov
A Moderate/weak. The parameter depends on other parameters evaluated as
Moderate/weak. The assumption that that exposed area will affect p exp strong
B High
C Moderate
Comments/recommendations:
A higher value is conservative. Coverage is calculated by the oil drift model.
Use Best Practice for oil drift simulation set-up to ensure comparable and
reliable predictions of the statistic
Texp
A Moderate/weak. The parameter depends on other parameters evaluated as
Moderate/weak. Based on stochastic result (i.e. estimated over the whole
simulation period). The assumption that the exposure time will affect p exp is
strong
B High
C High
Comments/recommendations:
A higher value is conservative. Exposure time is calculated by the oil drift
model. Use Best Practice input data and setup for the ODS to ensure
comparable and reliable predictions
p phy
A Moderate/weak. Due to lack of experimental data, it is difficult to assign a
specific p phy values. The assumption that the physiological factors will affect
p let is strong
B Low/Moderate/High, depending on VEC
Low for seabirds and moderate to high for marine and aquatic mammals and
sea turtles
C Moderate
Comments/recommendations:
A higher value is conservative. Each VEC have three estimates (low,
intermediate, high), using high is most conservative. Alternative, use all to
obtain larger credible interval
(continued)
5 Handling Uncertainty and Sensitivity …
Table 5.1 Summary of assessments or calculations used as basis for classification in the sea surface.
Impact and impact time parameters
Main parameter A: Strength of knowledge (function where it is used)
B: Belief that the value may deviate from the average assumption (natural
variation of parameter)
C: Sensitivity of function to parameter (sensitivity index)
p beh
A Moderate/weak. Due to limited data and large natural variation it is difficult
to assign a specific p beh value. The assumption that behavioural factors will
affect p exp is strong
B Moderate
C Moderate
Comments/recommendations:
A higher value is conservative. Each VEC have three estimates (low,
intermediate, high), using high is most conservative. Alternative, use all to
obtain larger credible interval
Cov
A Moderate/weak. The parameter depends on other parameters evaluated as
Moderate/weak. The assumption that that exposed area will affect p exp strong
B High
C Moderate
Comments/recommendations:
A higher value is conservative. Coverage is calculated by the oil drift model.
Use Best Practice for oil drift simulation set-up to ensure comparable and
reliable predictions of the statistic
Texp
A Moderate/weak. The parameter depends on other parameters evaluated as
Moderate/weak. Based on stochastic result (i.e. estimated over the whole
simulation period). The assumption that the exposure time will affect p exp is
strong
B High
C High
Comments/recommendations:
A higher value is conservative. Exposure time is calculated by the oil drift
model. Use Best Practice input data and setup for the ODS to ensure
comparable and reliable predictions
p phy
A Moderate/weak. Due to lack of experimental data, it is difficult to assign a
specific p phy values. The assumption that the physiological factors will affect
p let is strong
B Low/Moderate/High, depending on VEC
Low for seabirds and moderate to high for marine and aquatic mammals and
sea turtles
C Moderate
Comments/recommendations:
A higher value is conservative. Each VEC have three estimates (low,
intermediate, high), using high is most conservative. Alternative, use all to
obtain larger credible interval
(continued)