Possibility or Probability
Post by CatalinaNJB
That there is a possibility does not imply that there is
a probability.
Possibilities are variables while probabilities are facts.
Probabilities vary due to the effect of possibilities. A possibility is often
applied to safety as a fact with an undisputed path for an event to occur.
Possibility is the expression of a desire for an event to occur, while
probability is an analysis of facts to establish a likelihood level of an event
to occur. When possibilities are applied to regulatory compliance operations
gradually become a system failure, or a dysfunctional operation, while with the
application of probabilities the operations improves their safety, or functional
systems and operates with an effective SMS.
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| There is a possibility that all marbles remain in the bowl, but a low probability |
Probabilities are levels of the likelihood of one
possibility, or the confidence level of a prediction that an event will occur
in the future.
There is only one possibility applied, but this
possibility is applied to the different criteria of likelihood. Likelihood is
defined in many shapes and forms. One method is to define the likelihood of ten
independent levels based on a time-frame between events.
Likelihood levels could be defined as follows:
A) Inconceivable
·
Times between intervals are imaginary,
theoretical, virtual, or fictional.
B) Rarely
·
Times between intervals are beyond factors
applied for calculation of problem-solving in operation.
C) Remotely
·
Times between intervals are separated by breaks,
or spaced greater than normal operations could foresee.
D) Randomly
·
Times between intervals are without definite
aim, direction, rule, or method.
E) Variable
·
Times between intervals are indefinable.
F) Occasionally
·
Times between intervals are inconstant.
G) Often
·
Times between intervals are protracted and
infrequent.
H) Frequently
·
Times between intervals are reliable and
dependable.
I) Regularly
·
Times between intervals are short, constant and
dependable.
J) Systematically
·
Times between intervals are methodical, planned
and dependable, without defining the operational system or processes involved.
When applying examples to these likelihood levels they
become alive and practical in a Safety Management System.
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|
The likelihood is
inconceivable.
|
As an example, for each departure, there is a possibility
for an airplane to experience an engine failure just after liftoff. However,
the probability that this event occurs is based on data applied to a likelihood
level. By applying the possibility to each level of likelihood and pick one
level based on data it could be established what effect a possibility of an
engine failure has on operational safety for each likelihood level. In this
example the possibility is applied to a likelihood level of Randomly.
D) Randomly – an engine failure just after liftoff occurs
randomly. These intervals between engine failures are without definite aim,
direction, rule, or method.
However, when an engine failure is applied as a
possibility only, it becomes a possibility to an inconceivable event and there
could not be safety in aircraft operations.
The same scenario holds water when applying one
possibility to regulatory compliance. It
could be said, and it has been said that there is a possibility for an operator
to be non-compliant with one regulation and therefore a regulatory
non-compliance finding could be issued. When applying one possibility without a
link to likelihood all operations are non-conforming to regulatory requirements
and all operations becomes non-conforming to safety.
CatalinaNJB
