Compare shared-shoot charges before calling an equal split fair

Define the work being shared

A fictional studio is planning one photo shoot for three departments. Each department needs a different set of product scenes, but some preparation and production can be shared. The producer has a combined estimate and proposes dividing it equally. Before calling that proposal fair, the team needs to distinguish agreement about the creative work from agreement about who should bear its cost.

Build a scope sheet with one row per department. Name the intended assets, usage rights, delivery formats and acceptance conditions. Show which production elements would remain necessary if a department withdrew. Do not infer that two departments ask for equivalent work merely because each requests a similar number of finished images. A simple pack shot and a constructed setting may have different preparation needs.

Keep the shared plan coherent. If the fictional joint shoot relies on common lighting, a shared location or a coordinated delivery, the combination estimates must describe that arrangement consistently. A department cannot be assigned a charge for one service while receiving another. The purpose of the scope sheet is to make disagreements about the work visible before they become arguments about the allocation formula.

Use the supplied toy costs below only for the exercise. For a real proposal, distinguish a supplier estimate from an internal assumption and identify missing combinations. Do not invent a quotation to fill a convenient cell. A mathematically complete worksheet does not establish that every hypothetical production arrangement can actually be purchased.

Calculate the stated alternative without changing the scope

Kesselheim defines a Shapley cost share as the average joining-cost increment over every participant order. Here costs are fictional GBP thousands: none 0; A 6, B 8, C 10; AB 10, AC 12, BC 14; ABC 15. Each coalition cost covers its stipulated combined shoot.

For orders ABC, ACB, BAC, BCA, CAB, CBA, the increments listed consistently as (A, B, C) are (6, 4, 5), (6, 3, 6), (2, 8, 5), (1, 8, 6), (2, 3, 10), (1, 4, 10). Averaging gives (3, 5, 7), totaling 15. Equal division instead gives (5, 5, 5). Neither changes the total shoot cost.

This is a cost-sharing convention, not evidence of departmental revenue contribution or a uniquely fair commercial agreement.

Read each increment row with the participant labels beside it. The order names describe the calculation, not the actual shooting schedule or the order in which invoices will be paid. Keep that distinction in the presentation so a production coordinator does not interpret the exercise as a new operating plan.

The local check enumerates the six orders and independently groups the increments by the set of departments already present. Both exact calculations agree. No supplier service was booked and no departmental account was changed. Preserve the complete cost inputs with the comparison so another reviewer can reproduce the proposal rather than trust the displayed totals.

If a department disputes an input, identify the disputed combination and return to the matching scope. For example, a quoted combination might omit a required retouch or a delivery license. Correct the underlying proposal before arguing over its calculated share. The formula is not a reason to hide a missing deliverable or to treat an unsupported estimate as an accepted price.

Choose a basis the participants can actually evaluate

Present the equal-share proposal and the calculated alternative side by side, each linked to the same creative brief. Ask the department owners what principle they intend their agreement to reflect. They may value administrative simplicity, the work requested, a prior internal commitment or another explicitly stated consideration. The exercise does not authorize the producer to replace an existing agreement merely because a different calculation is available.

Keep the discussion about the proposed production arrangement rather than the perceived prestige of each department. Do not describe a higher proposed charge as evidence that a team is more valuable to the business or that its campaign will generate more sales. The scope sheet describes requested work; the arithmetic does not assess staff performance or establish commercial impact.

Record objections in a form that can be resolved. A participant may disagree with a specific scope assumption, the proposed sharing basis or the authority to charge its budget. Those are different issues. Ask for the missing evidence or decision in the appropriate place instead of treating every objection as an arithmetic error. Retain the unaccepted proposal so later revisions do not make the earlier discussion impossible to follow.

If the authorized owners prefer another basis, explain that choice directly. Do not select a formula only because it gives a favored department the lowest charge and then describe the outcome as inevitable. A useful handoff exposes the proposed basis and its consequences while leaving the actual agreement to the people authorized to make it.

Carry the accepted scope into the eventual handoff

Prepare a short comparison pack containing the fictional scope sheet, all supplied combination costs, the two proposed charge schedules and the unresolved decision. Label it as an exercise rather than a supplier quotation. Its reader should be able to separate the price of the joint work from the internal proposal for sharing that price.

Before any real arrangement is considered, the relevant owners would need to confirm the production scope, commercial terms and authority to use their budgets. This lesson makes none of those commitments. Do not turn the teaching result into an invoice or alter an internal account. A cost-sharing explanation is useful preparation, but it is not permission to spend or collect money.

When a future scope changes, retain the earlier comparison and identify the changed deliverable before preparing a revised proposal. Adding another scene, extending usage or removing a department can change the substance of the arrangement. Avoid attaching the old charge schedule to a new brief simply because the total still looks affordable. The completed artifact should let a reviewer trace a proposed charge to the exact work and decision it belongs to.

Make the reasoning concrete.

A producer has one joint shoot estimate and wants to send each department a proposed charge, but the participants have not agreed on the basis.

Choose the transparent comparison and keep all real charges uncommitted.

Take the questions into your next brief.

Use these prompts in your own notes. Nothing is submitted from this page.

1. Scope

   Which assets and rights does each department receive?

2. Inputs

   Does every combination cost describe the same underlying requirements?

3. Calculation

   Can the complete increment rows be reconstructed?

4. Agreement

   Which sharing principle are the owners being asked to accept?

5. Handoff

   What remains unresolved before any actual charge?

Watch for the wrong conclusion.

• Filling a missing combination with an invented supplier quote.
• Treating a proposed charge as a judgment of a department’s commercial importance.
• Attaching an old allocation to a changed production brief.

Sources & scope

Original fictional production scope and cost inputs. The lecture supports the stated cost-sharing calculation. Exact offline arithmetic only; no quotation, charge, account or contract was changed.

• Cost Sharing, Lecture 25 →Primary university lecture notes · Supports: Cost functions and order-averaged increments.