Value of Information Interview Intuition
Value of information interview intuition for deciding whether extra observations, signals, or samples are worth their cost.
Candidates facing observe-or-act, sample-or-stop, and signal-purchase expected value prompts.
Information has value only if it can change action
Extra information is valuable when it can lead to a better decision than acting immediately. If the same action would be chosen either way, the information may have zero decision value.
Compare before and after
Compute the best expected value without the information, then compute the expected value of the policy that observes the information and acts conditionally.
Subtract information cost
A signal, sample, or reveal is worth buying only if the expected improvement exceeds the cost of obtaining it.
Concrete example
If observing a signal improves your expected payoff by 0.80 but costs 1.00, the net value of information is -0.20 under the toy model.
Identify zero-value cases
Information has no practical value when it is irrelevant, too noisy to change the posterior enough, or arrives after the decision must already be made.
Common mistakes
Candidates often value information by how interesting it sounds rather than by whether it changes the optimal action after cost.
Practice the pattern
Use the LeetQuidity curriculum and calibration to turn this topic into a focused practice plan.