Risk vs. Uncertainty
You find yourself stranded on a deserted island with limited resources. You need to decide on the best course of action to survive until rescue arrives. Unfortunately, the timing of rescue is uncertain.
Using the concepts covered in this chapter, discuss the following:
- Risk vs. Uncertainty:
o Why is this situation a classic example of decision-making under uncertainty, rather than risk?
o How does uncertainty differ from risk, where you can assign probabilities to different outcomes? - Expected Utility Theory:
o Imagine you have some basic survival tools and a faint signal on your radio. Expected utility theory helps make decisions under risk. Can you apply this concept if you don’t know the probability of rescue? - Decision Rules under Uncertainty:
o Given the uncertainty about rescue timing, what are some decision-making rules you could consider?
Maximax – Choose the option with the highest possible payoff (optimistic approach).
Maximin – Choose the option with the highest payoff in the worst-case scenario (pessimistic approach).
Minimax Regret – Choose the option that minimizes your potential regret (considering the difference between your chosen option and the best alternative outcome under each scenario).
Equal Probability Rule – Assign equal probabilities to all possible scenarios and choose the option with the highest average expected payoff (assuming no knowledge about actual probabilities).
- Choosing a Strategy:
o Discuss the advantages and disadvantages of each decision rule (maximax, maximin, minimax regret, equal probability) in the context of your island survival situation.
o Which rule might be most appropriate, considering the potential consequences of each choice?
Sample Answer
Stranded on a deserted island, my survival hinges on making sound decisions under extreme uncertainty. Let’s analyze this using the concepts you’ve provided.
1. Risk vs. Uncertainty:
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Why Uncertainty? This situation epitomizes decision-making under uncertainty, not risk. In a risk scenario, I could assign probabilities to different outcomes (e.g., a 70% chance of rescue within a week, a 30% chance within two weeks). Here, I have no such information. I don’t know when rescue will come, making it impossible to assign meaningful probabilities. The timing of rescue is the key uncertain variable.