Most decisions in the petroleum industry involve elements of
risk and uncertainty, particularly in the area of oil exploration.
When a decision is made to drill an exploratory oil well, company
geologists and engineers are not able to measure or define specific
values of factors contributing to overall profit (or loss) at the
time of the decision. In addition, future events that could affect
timing and/or size of projected cash flows from the prospective
well (e.g., government price controls, cessation of oil imports
from Iraq) cannot be reliably predicted. These risks and
uncertainties have decision-makers in the oil industry relying more
and more on decision analysis techniques. Chi U. Ikoku, Associate
Professor and Associate Director of Drilling Research at the
University of Tulsa, writes: "Decision analysis methods provide new
and much more comprehensive ways to evaluate and compare the degree
of risk and uncertainty associated with each [oil] investment
choice. The net result is that the decision-maker is given a
clearer insight of potential profitability and the likelihoods of
achieving various levels of profitability than older, less formal
methods of investment analysis. Because of rising drilling costs,
the need to search for petroleum in deeper horizons or in remote
areas of the world, increasing government control, etc., most
petroleum exploration decision-makers are no longer satisfied to
base decisions on experience, intuition, rules of thumb, or similar
approaches. Instead, they recognize that better ways to evaluate
and compare drilling investment strategies are needed. Decision
analysis is fulfilling this need." Ikoku lists several distinct
advantages that decision analysis has over the less formal oil
drilling decision-making techniques used in the past:
1. Decision analysis forces the decision-maker to consider all possible alternatives and their corresponding outcomes. 2. Decision analysis provides an excellent way to evaluate the sensitivity of various oil-drilling factors to overall profitability. 3. Decision analysis provides a means to compare the relative desirability of drilling prospects having varying degrees of risk and uncertainty. 4. Decision analysis is a convenient and unambiguous way to communicate judgements about risk and uncertainty. 5. Exceedingly complex oil investment options can be analyzed using decision analysis. The decision-making technique discussed in his World Oilarticle is the expected value criterion. This procedure requires the decision-maker to assess the probability of occurrence of each possible state of nature. "Assigning probabilities of occurrence to various outcomes of a petroleum venture," says Ikoku, "requires the cooperative judgement and skills of geologists, engineers, and geophysicists." Some of the types of risks that oil investors commonly encounter and consequently need to assess are: risk of an exploratory or development dry well; political risk; economic risk; risk relating to future oil and gas prices; risk of storm damage to offshore installation; risk that an oil discovery will not be large enough to recover initial exploratory costs; risk of at least a given number of oil discoveries in a multi-well drilling program; environmental risk; and risk of a gambler's ruin. Because of certain characteristics that are unique to a petroleum exploration, these state-of-nature probabilities cannot be determined exactly, and furthermore, their estimates often must be made on the basis of very little or no statistical data or experience. (Additional data can be obtained from additional wells, but, says Ikoku, " normally, delaying decisions until there is sufficient data upon which to base probability estimates cannot be afforded." Thus, the decision-maker usually must rely on his or her subjective judgment or past success ratios in order to assess the state-of-nature probabilities. As an illustration of how decision analysis may be applied to the petroleum industry, Ikoku presented the following example: A company is considering the purchase of 320 net acres in a proposed 640-acre oil unit. Three decision alternatives or actions are available to the company: a1: Participate in the unit (i.e., drill) with non-operating 50% working interest. a2: Farm out, but retain 1/8 of 7/8 overriding royalty interest. a3: Be carried under penalty with a back-in privilege after recovery of 150% of investment by participating parties. The possible outcomes or states of nature and their corresponding probabilities, based on detailed geological and engineering analyses of the prospect and surrounding wells, are given in Table 19.17. Since the company will base its decision on the objective variable Net Profit, the projected net profits for the action/state-of-nature combinations were determined as shown in Table 19.18 (a) Construct a payoff table for the oil-investment decision problem. (b) Using the expected payoff criterion, which of the three alternative actions should the company accept? (c) What is the maximin decision? The maximin dicision? (d) Construct an opportunity loss table for the oil investment decision problem and find the minimax regret decision. Table 19.17 state of nature= probability Dry hole=.30 Unit produces 20000 barrels=.25 unit produces 40000 barrels=.25 unit produces 80000 barrels=.10 unit produces 100000 barrels=.10 Table 19.18 Drill/dryhole=-40000 Drill/20000=50000 Drill/40000 bbls=300000 Drill/80000 bbls=700000 drill/100000=800000 farm out/dry hole=0 farm out/20000 bbls=12000 farm out/40000=60000 farm out/80000=120000 farm out/100000=130000 backinoption/dry hole=0 backinoption/20000=12000 backinoption/40000=145000 backinoption/80000=400000 backinoption/100000=500000
1. Decision analysis forces the decision-maker to consider all possible alternatives and their corresponding outcomes. 2. Decision analysis provides an excellent way to evaluate the sensitivity of various oil-drilling factors to overall profitability. 3. Decision analysis provides a means to compare the relative desirability of drilling prospects having varying degrees of risk and uncertainty. 4. Decision analysis is a convenient and unambiguous way to communicate judgements about risk and uncertainty. 5. Exceedingly complex oil investment options can be analyzed using decision analysis. The decision-making technique discussed in his World Oilarticle is the expected value criterion. This procedure requires the decision-maker to assess the probability of occurrence of each possible state of nature. "Assigning probabilities of occurrence to various outcomes of a petroleum venture," says Ikoku, "requires the cooperative judgement and skills of geologists, engineers, and geophysicists." Some of the types of risks that oil investors commonly encounter and consequently need to assess are: risk of an exploratory or development dry well; political risk; economic risk; risk relating to future oil and gas prices; risk of storm damage to offshore installation; risk that an oil discovery will not be large enough to recover initial exploratory costs; risk of at least a given number of oil discoveries in a multi-well drilling program; environmental risk; and risk of a gambler's ruin. Because of certain characteristics that are unique to a petroleum exploration, these state-of-nature probabilities cannot be determined exactly, and furthermore, their estimates often must be made on the basis of very little or no statistical data or experience. (Additional data can be obtained from additional wells, but, says Ikoku, " normally, delaying decisions until there is sufficient data upon which to base probability estimates cannot be afforded." Thus, the decision-maker usually must rely on his or her subjective judgment or past success ratios in order to assess the state-of-nature probabilities. As an illustration of how decision analysis may be applied to the petroleum industry, Ikoku presented the following example: A company is considering the purchase of 320 net acres in a proposed 640-acre oil unit. Three decision alternatives or actions are available to the company: a1: Participate in the unit (i.e., drill) with non-operating 50% working interest. a2: Farm out, but retain 1/8 of 7/8 overriding royalty interest. a3: Be carried under penalty with a back-in privilege after recovery of 150% of investment by participating parties. The possible outcomes or states of nature and their corresponding probabilities, based on detailed geological and engineering analyses of the prospect and surrounding wells, are given in Table 19.17. Since the company will base its decision on the objective variable Net Profit, the projected net profits for the action/state-of-nature combinations were determined as shown in Table 19.18 (a) Construct a payoff table for the oil-investment decision problem. (b) Using the expected payoff criterion, which of the three alternative actions should the company accept? (c) What is the maximin decision? The maximin dicision? (d) Construct an opportunity loss table for the oil investment decision problem and find the minimax regret decision. Table 19.17 state of nature= probability Dry hole=.30 Unit produces 20000 barrels=.25 unit produces 40000 barrels=.25 unit produces 80000 barrels=.10 unit produces 100000 barrels=.10 Table 19.18 Drill/dryhole=-40000 Drill/20000=50000 Drill/40000 bbls=300000 Drill/80000 bbls=700000 drill/100000=800000 farm out/dry hole=0 farm out/20000 bbls=12000 farm out/40000=60000 farm out/80000=120000 farm out/100000=130000 backinoption/dry hole=0 backinoption/20000=12000 backinoption/40000=145000 backinoption/80000=400000 backinoption/100000=500000
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