Project Risk Management - Advantages And Pitfalls Page 3

ADVERTISEMENT

3
Now when should a risk analysis be performed? Certainly it is not always appropriate
but if there are multiple numerical uncertainties and these uncertainties cause concern, the use
of risk analysis techniques is advisable.
The question often arises as to how a highly sophisticated technique like Monte Carlo
simulation can possibly apply to projects for which much information is not precisely defined
in advance. After all, Monte Carlo simulation was developed for very precise applications
(like the atomic bomb) and, as such, generally requires great accuracy and precision in data
inputs and well-defined probability density functions for the various variables. By
comparison, cost and schedule information on engineering projects is rarely precise.
Estimates are opinions of probable cost, not highly accurate answers.
The reason Monte Carlo approaches can be applied to engineering projects is that
decision-makers don’t expect precise answers. They generally are willing to accept variances
of 5 to 10% when making decisions related to quantitative values involving risk. By
comparison, in highly scientific fields, errors of this magnitude cannot be tolerated. Such is
not the case in engineering and construction. It's a different world. Because it is a different
world and because we are more tolerant of some error in engineering or construction projects,
we can de-escalate the requirements for the user of Monte Carlo.
The risk analyst must understand that the primary concern in the minds of managers is
how large the economic exposure is if the project is authorized. Few managers will accept a
project with a low probability of success and a high exposure. Managers rarely are risk takers.
They are risk averse.
Often the worst case scenario approach is used to estimate exposure. In this approach,
all major variables are estimated at their most extreme unfavorable values and the exposure is
calculated. The results are inevitably horrible. They are the theoretical worst case. They are so
mathematically remote that at best they are useless; at worst they are misleading. Even in a
highly risky project, not every variable will go to its unfavorable extreme value. Some
variables will show little variance from the plan and others may deviate in the favorable
direction. Therefore the actual exposure generally is much less than the worst case scenario.
Monte Carlo Simulation can identify what the actual exposure really is and what the
probability of success is.
If, for example, you have performed a risk analysis and told management that they
have a 80% chance of success but that they have a 45% exposure, what does that mean? That
means that the bottom line decision variable can erode by as much as 45% of the target value.
"Why?" will be the next question they'll ask. "Why will it be that way?" They will
want to look at a ranked list of risks and opportunities so that they can search for controllables
and can challenge the management team to come up with alternative strategies and tactics.
These alternatives can then be tested in the Monte Carlo environment to arrive at an optimum
solution.
Monte Carlo is not only a great tool for evaluating a current plan; it's a marvellous tool
for evolving a better one.
Contingency
In any estimate or project plan the estimators always include an item at the end of the
estimate for contingencies. A contingency allowance is necessary because uncertainty exists
in the estimating data and assumptions. The costs cannot be defined precisely when the
estimates are made. To account for this many companies tend to use an allowance of about
10% for contingencies in their estimates. In some cases, the 10% allowance is company
policy. All their estimates include a 10% contingency. This is totally fallacious. The amount

ADVERTISEMENT

00 votes

Related Articles

Related forms

Related Categories

Parent category: Business
Go
Page of 6