Data & measurement
Impact scoring combines total impact TI with ceiling-relative indices. Report both raw TI and IS when comparing scenarios. Write explicit operational definitions for each symbol in your protocol, even when abbreviations look standard. Log instrument versions, sample frames, and cleaning rules whenever estimates are refreshed so longitudinal comparisons stay valid.
Solution & proof
Conceptual summary: Scenario comparison over horizon T: difference in TI between end and start of the simulation. Treat this as a measurement recipe: map each symbol to an empirical quantity, substitute estimates, and simplify with ordinary algebra (including logarithms, min/max caps, or piecewise branches where shown). Where limits or integrals appear, approximate with discrete sums on cohorts or time steps when closed forms are impractical. Interpret the result against thresholds in the cited source and report uncertainty on inputs.
Examples
1. Word problem — pilot estimates
Word problem
Evaluate “Projected impact gain ΔTI” using the provisional estimates in the table. Compute the outcome with the formula at the top of this page.
Provisional estimates for substitution (illustrative)
Item Estimate Primary input A 0.62 Primary input B 0.78 Scaling / time factor 1.0 Solution
Step 1 — From the table, assign a = 0.62; b = 0.78; T = 1.
Step 2 — Substitute into the definition of “Projected impact gain ΔTI” at the top of the page (same structure as the source formula).
Step 3 — Finish any remaining algebra (sums, caps, logs, or limits) by hand or in a CAS when the expression still contains Σ, integrals, or non-numeric parameters. Tie final numbers back to your corpus or community records.
2. Check — revised primary input
Word problem
The same measure applies with a revised first input when a late survey batch arrives (see table).
Updated provisional estimates (illustrative)
Item Estimate Primary input A a 0.71 Primary input B b 0.78 Scaling / time factor T 1.0 Solution
Step 1 — From the table, assign a = 0.71; b = 0.78; T = 1.
Step 2 — Substitute into the definition of “Projected impact gain ΔTI” at the top of the page (same structure as the source formula).
Step 3 — Finish any remaining algebra (sums, caps, logs, or limits) by hand or in a CAS when the expression still contains Σ, integrals, or non-numeric parameters. Tie final numbers back to your corpus or community records.
Source
Impact measurement framework — Impact Scoring