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Learn through experiments

One shipment, competing service goals

Does maximizing a weighted score produce fair service?

Entering midway? Revisit Extra copies cannot fix every failure for the preceding worked example, or start here and use the explanation below.

1 · Try

Start with a concrete question

Original synthetic scenario. Three branches each need eight items. A shipment suffers a selected damage fraction; allocation rules prioritize arrival order, equal turns, or assumed benefit.

Try the initial inputs, then write a prediction before changing one setting. All calculations run locally on your CPU.

Go directly to the experiment · Review basic mathematics

2 · Predict

What do you expect?

Can policies fulfill the same total demand but leave very different minimum service?

3 · Experiment

Change one thing. Inspect what happens.

  1. Compare policies at the same usable inventory and inspect every branch.
  2. Contrast total fulfillment, minimum service, and benefit points.
  3. Increase damage and test whether your chosen policy still meets a service floor.
  4. Justify a rule and state whose needs are not captured by the invented weights.
Experiment inputs
Inputs
Your settingsMechanism
Calculation belowEvidence
Compare outcomes
Usable inventory9 items
Total fulfilled9 items
Lowest branch fulfillment0 %
Programmed benefit10 points

Compare the current results

Every bar starts at zero and uses the same numeric scale in this chart. The upper bound automatically adjusts to the largest current value (at least 1), so compare the numbers when changing inputs. Units and quantities come from each label; different kinds of quantity are not interchangeable. Displayed values are rounded to at most six significant digits.
08
  • Branch 1 supplied (items)8
    Branch 1 supplied (items): 8Horizontal bar from zero to 8, on the shared zero to 8 numeric axis.
  • Branch 2 supplied (items)1
    Branch 2 supplied (items): 1Horizontal bar from zero to 1, on the shared zero to 8 numeric axis.
  • Branch 3 supplied (items)0
    Branch 3 supplied (items): 0Horizontal bar from zero to 0, on the shared zero to 8 numeric axis.

Follow the calculation

  1. Usable inventory = floor(12 × (1 − 0.2)) = 9; each branch needs 8.
  2. Branch 1: allocated 8/8, assumed benefit 1 points/item, contribution 8.
  3. Branch 2: allocated 1/8, assumed benefit 2 points/item, contribution 2.
  4. Branch 3: allocated 0/8, assumed benefit 4 points/item, contribution 0.
  5. Total benefit = 10; minimum service fraction = 0/8.

Equal total fulfillment can conceal unequal service. Prioritizing the modeled benefit may improve a score while leaving a branch unserved; the weights are a decision assumption.

Captures keep your inputs, prediction and observation. Results are recalculated from those inputs. Resetting inputs keeps your captures and challenge history.

4 · Understand

Explain the mechanism

What the experiment explains

Original synthetic scenario. Three branches each need eight items. A shipment suffers a selected damage fraction; allocation rules prioritize arrival order, equal turns, or assumed benefit.

Allocation distributes a fixed scarce stock; the rule changes who receives it. The model assigns benefit weights 1, 2 and 4, explicitly as assumptions.

With 12 incoming items and 20% damage, floor(9.6)=9 are usable. Branch-order allocation gives [8,1,0], while round-robin gives [3,3,3]. Both fulfill nine items, but minimum service differs.

Prioritizing the highest weight can maximize the programmed benefit while producing zero service at a branch. A decision needs an explicit objective and constraints, not merely a high score.

Read the relationship

Usable stock = floor(shipment × (1−damage fraction)). Benefit = sum(allocation × branch weight). Minimum service = minimum branch allocation / 8.

Inspect the evidence

The numerical trace is recalculated from your current settings. Compare a controlled pair of trials before changing several inputs together. Inspect intermediate quantities as well as final metrics; state which assumptions make the comparison meaningful.

Boundaries of the model

  • Fixed demands and weights, no transport costs, branch substitution or future replenishment.
  • The benefit index is invented and does not establish ethical or economic value.

Return to the systems thinking and operations course and project to connect this mechanism to the broader investigation.

5 · Apply

Try a fresh case

A new shipment has 15 items, 20% damaged. Three equal branches receive stock round-robin. How many usable items does each receive?

This is a public practice check. Retries support learning; matching a number does not certify independent proficiency.

Take the investigation further

Choose any extension. These are project prompts for you to carry out; they are not automatically assessed.

School investigation

Compare allocation rules and defend a service floor.

College investigation

Implement a constrained allocation optimizer with independently checked feasibility.

Workplace investigation

Draft a shortage policy with stakeholder priorities, minimum service, damaged-stock handling and appeal rules.

6 · Continue

Keep the evidence, choose your next step

Completion records your own decision that you have worked through this investigation. Practice checks and independent project evidence are separate.