Problem Definition

The model is usually defined through a spreadsheet workbook. This section details the data input requirements.

Workbook Sheets

Mandatory sheets:

Impact Multipliers - imp Define the uncertain impact differentiators, their distributions, and how they combine with organization characteristics.
Correlation Matrix - cov Define correlations between impact multipliers, and optionally between organization noise modifiers.
Organization Characteristics - fos Define how each organization scores on each impact differentiator.
Funding Parameters - meta Define the budget, time horizon, and optional virtual-organization settings.
Organization Funding - orgmeta Define room for funding, diminishing-returns parameters, year availability, and model coverage for each organization.

Optional sheets:

Formulas - formulas Define derived variables using formulas instead of sampling them directly.

Optional supporting sheets:

Custom Distributions - separate sheets referenced from imp, not a literal tab named custom_distributions Provide empirical value lists for multipliers that use Distribution = custom.

The engine initializes workbook inputs in this order:

This matters because later sheets can depend on information or defaults established earlier. For example:

cov is filtered against the final multiplier set.
orgmeta uses meta$Years to validate Available in year X.
fos can reference formula-generated differentiators that are added to the multiplier table later.

Each page in this section is written as a parser contract:

accepted structure,
defaults and inferred values,
validation behavior,
implementation details that are easy to miss when reading only the spreadsheet examples.

If you are updating example workbooks or creating agent prompts, prefer these pages over older prose descriptions.